morphine and Meconium-Aspiration-Syndrome

Meconium is a common finding in amniotic fluid and placental specimens, particularly in term and post-term pregnancies. The objective of this paper was to perform a meta-analysis to examine the impact of endotracheal suctioning on the occurrence of meconium aspiration syndrome (MAS), mortality, and complications.. PubMed, EMBASE, and the Cochrane library were systematically searched for comparative studies. Odds ratios (ORs), weighted mean differences (WMDs), and corresponding 95% confidence intervals (CIs) were used to compare the outcomes.. Twelve studies were included in the meta-analysis. There were no significant impacts of endotracheal suctioning on the occurrence of MAS (OR = 3.05, 95% CI: 0.48-19.56), mortality (OR = 1.25, 95% CI: 0.35-4.44), the need for mechanical ventilation (OR = 4.20, 95% CI: 0.32-54.72), the occurrence of pneumothorax (OR = 0.99, 95% CI: 0.34-2.85), persistent pulmonary hypertension of the newborn (PPHN), (OR = 1.31, 95% CI: 0.58-2.98), hypoxic-ischemic encephalopathy (HIE) (OR = 0.82, 95% CI: 0.52-1.30), and length of stay (WMD = -0.11, 95% CI: -0.99-0.77).. Routine endotracheal suctioning at birth is not useful in preventing MAS, mortality, mechanical ventilation, PPHN, HIE, and prolonged length of stay in neonates born through MSAF.. · Routine suctioning is not recommended for newborns.. · Endotracheal aspiration is not beneficial for MAS.. · Future research may focus on selected neonates..

Topics: Amniotic Fluid; Female; Humans; Infant; Infant, Newborn; Meconium; Meconium Aspiration Syndrome; Parturition; Persistent Fetal Circulation Syndrome; Placenta; Pregnancy

The 2015 recommendation of the International Liaison Committee on Resuscitation of no routine tracheal suctioning in non-vigorous neonates born through meconium-stained amniotic fluid (MSAF) was based on very low certainty of evidence (CoE) necessitating ongoing monitoring. The aim of this systematic review was to perform a meta-analysis of observational studies comparing the effect of implementing immediate resuscitation without routine tracheal suctioning versus with routine suctioning in neonates born through MSAF.. MEDLINE, Embase, CENTRAL, and Web of Science were searched. Observational studies with a before-and-after design were included. Two authors extracted data independently. CoE based on GRADE recommendations was performed.. 13 studies were included. Clinical benefit or harm could not be excluded for the composite primary outcome of mortality or requirement of extracorporeal membranous oxygenation (ECMO) (relative risk, 95% confidence interval: 0.74 [0.47-1.17]), and mortality (0.68 [0.42-1.11]). "Routine tracheal suctioning" epoch had possibly lesser risk of meconium aspiration syndrome (MAS) when compared to "no routine tracheal suctioning" epoch (0.68 [0.47-0.99]). "Routine tracheal suctioning" epoch also possibly had a lower risk of hospital admission for respiratory symptoms, requirement of non-invasive respiratory support, invasive mechanical ventilation, surfactant treatment, air leak, and low-flow oxygen therapy. Clinical benefit or harm could not be excluded for the outcome of mortality or ECMO among those diagnosed with MAS (1.09 [0.86-1.39]), but "routine tracheal suctioning" was possibly associated with lower risk of respiratory morbidities among those diagnosed with MAS. The CoE was very low for most of the outcomes evaluated.. Due to the very low CoE for the outcomes evaluated, no definitive conclusions can be drawn warranting the need for additional studies.

Topics: Amniotic Fluid; Female; Humans; Infant; Infant, Newborn; Meconium; Meconium Aspiration Syndrome; Observational Studies as Topic; Randomized Controlled Trials as Topic; Respiration, Artificial

Neonates born through meconium-stained amniotic fluid (MSAF) may develop complications including meconium aspiration syndrome, persistent pulmonary hypertension of newborn and death. The approach to the resuscitation of these neonates has significantly evolved for the past few decades. Initially, under direct visualization technique, neonates with MSAF were commonly suctioned below the vocal cords soon after delivery. Since 2015, Neonatal Resuscitation Program (NRP. 出生于羊水胎粪污染的新生儿可发生新生儿胎粪吸入综合征、持续性肺动脉高压等并发症，甚至死亡。在过去的几十年里，羊水胎粪污染新生儿复苏已发生了几次重要的变革。最初，对于羊水胎粪污染新生儿，通常在其出生后立即采用喉镜直视下吸引声门下胎粪。自2015年起，美国儿科学会新生儿复苏指南不再推荐对羊水胎粪污染无活力新生儿“常规”给予气管插管吸引胎粪，但建议立即给予气囊面罩正压通气复苏。然而，最新版2021年中国新生儿复苏指南仍保留对无活力新生儿进行胎粪吸引的建议。该文旨在探讨过去60年中美两国新生儿复苏指南在羊水胎粪污染新生儿复苏方法中的差异及其原因。.

Topics: Amniotic Fluid; Child; China; Female; Humans; Infant, Newborn; Infant, Newborn, Diseases; Intubation, Intratracheal; Meconium; Meconium Aspiration Syndrome; Resuscitation

Green-stained amniotic fluid, often referred to as meconium-stained amniotic fluid, is present in 5% to 20% of patients in labor and is considered an obstetric hazard. The condition has been attributed to the passage of fetal colonic content (meconium), intraamniotic bleeding with the presence of heme catabolic products, or both. The frequency of green-stained amniotic fluid increases as a function of gestational age, reaching approximately 27% in post-term gestation. Green-stained amniotic fluid during labor has been associated with fetal acidemia (umbilical artery pH <7.00), neonatal respiratory distress, and seizures as well as cerebral palsy. Hypoxia is widely considered a mechanism responsible for fetal defecation and meconium-stained amniotic fluid; however, most fetuses with meconium-stained amniotic fluid do not have fetal acidemia. Intraamniotic infection/inflammation has emerged as an important factor in meconium-stained amniotic fluid in term and preterm gestations, as patients with these conditions have a higher rate of clinical chorioamnionitis and neonatal sepsis. The precise mechanisms linking intraamniotic inflammation to green-stained amniotic fluid have not been determined, but the effects of oxidative stress in heme catabolism have been implicated. Two randomized clinical trials suggest that antibiotic administration decreases the rate of clinical chorioamnionitis in patients with meconium-stained amniotic fluid. A serious complication of meconium-stained amniotic fluid is meconium aspiration syndrome. This condition develops in 5% of cases presenting with meconium-stained amniotic fluid and is a severe complication typical of term newborns. Meconium aspiration syndrome is attributed to the mechanical and chemical effects of aspirated meconium coupled with local and systemic fetal inflammation. Routine naso/oropharyngeal suctioning and tracheal intubation in cases of meconium-stained amniotic fluid have not been shown to be beneficial and are no longer recommended in obstetrical practice. A systematic review of randomized controlled trials suggested that amnioinfusion may decrease the rate of meconium aspiration syndrome. Histologic examination of the fetal membranes for meconium has been invoked in medical legal litigation to time the occurrence of fetal injury. However, inferences have been largely based on the results of in vitro experiments, and extrapolation of such findings to the clinical setting warrants caution. Fetal defecatio

Topics: Amniotic Fluid; Chorioamnionitis; Female; Heme; Humans; Infant, Newborn; Inflammation; Meconium; Meconium Aspiration Syndrome; Pregnancy; Pregnancy Complications

This study aimed to reassess the effect of prophylactic transcervical amnioinfusion for intrapartum meconium-stained amniotic fluid on meconium aspiration syndrome and other adverse neonatal and maternal outcomes.. From inception to November 2021, a systematic search of the literature was performed in PubMed, Embase, Web of Science, and Scopus databases and gray literature sources.. We identified randomized controlled trials of patients with intrapartum moderate to thick meconium-stained amniotic fluid that evaluated the effect of amnioinfusion on adverse neonatal and maternal outcomes.. Of note, 2 reviewers independently abstracted data and gauged study quality by assigning a modified Jadad score. Meconium aspiration syndrome constituted the primary outcome. The secondary outcomes were meconium below the cords, Apgar scores of <7 at 5 minutes, neonatal acidosis, cesarean delivery, cesarean delivery for fetal heart rate abnormalities, neonatal intensive care unit admission, and postpartum endometritis. This study calculated the odds ratios with 95% confidence intervals for categorical outcomes and weighted mean differences with 95% confidence intervals for continuous outcomes.. A total of 24 randomized studies with 5994 participants met the inclusion criteria. The overall odds of meconium aspiration syndrome was reduced by 67% in the amnioinfusion group (pooled odds ratio, 0.33; 95% confidence interval, 0.21-0.51). Except for postpartum endometritis, amnioinfusion was associated with a significant reduction in all secondary outcomes.. Our study found that the use of intrapartum amnioinfusion in the setting of meconium-stained amniotic fluid significantly reduces the odds of meconium aspiration syndrome and other adverse neonatal outcomes.

Topics: Amnion; Amniotic Fluid; Endometritis; Female; Humans; Infant, Newborn; Meconium; Meconium Aspiration Syndrome; Obstetric Labor Complications; Pregnancy; Sodium Chloride

Before 2015, major changes in Neonatal Resuscitation Program (NRP) recommendations not supporting previously endorsed antepartum, intrapartum and postpartum interventions to prevent meconium aspiration syndrome were based on adequately powered multicenter randomized controlled trials. The 2015 and 2020 American Heart Association guidelines and 7th and 8th edition of NRP suggest not performing routine intubation and tracheal suctioning of nonvigorous meconium-stained newborns. However, this was given as a weak recommendation with low-certainty evidence. The purpose of this review is to summarize the evidence and explore the question of appropriate delivery room management for nonvigorous meconium-stained newborns.

Topics: Amniotic Fluid; Female; Humans; Infant, Newborn; Intubation, Intratracheal; Meconium; Meconium Aspiration Syndrome; Multicenter Studies as Topic; Resuscitation; United States

To compare short-term outcomes of infants born with thick versus thin meconium stained amniotic fluid (MSAF) and to perform a systematic review of the topic.. A retrospective, single center, cohort study of infants' ≥34 weeks' gestation born with MSAF between 1 June 2013 and 30 September 2016. Birth resuscitation and respiratory outcomes were compared between the groups. A systematic review was conducted of similar studies published between 1 January 2000 and 30 June 2019.. 1507 infants were eligible; 464 (30.8%) thick, 1,043 (69.2%) thin MSAF. The thick group required more respiratory support at birth and was 5.5-fold (95% CI: 2.51-11.95) more likely to and have meconium aspiration syndrome (MAS) and 2.1-fold more likely (95% CI: 0.89-4.83) to require either noninvasive respiratory support or intubation than the thin group. The thick group also had significantly higher oxygen supplementation >24 h (. Infants with thick MSAF required more intensive birth resuscitation and ventilation support. Our findings need confirmation in robust, prospective cohort studies.

Topics: Amniotic Fluid; Cohort Studies; Humans; Infant; Infant, Newborn; Meconium; Meconium Aspiration Syndrome; Prospective Studies; Retrospective Studies

We aimed to systematically review and analyse the outcomes of non-endotracheal suctioning (non-ETS) versus ETS in non-vigorous meconium-stained neonates.. We conducted a systematic review of non-ETS and ETS in non-vigorous infants born through meconium-stained amniotic fluid (MSAF). We searched PubMed/Medline, Scopus, Clinical Trials.gov, Cumulative Index to Nursing and Allied Health, and Cochrane Library databases from inception to November 2019, using keywords and related terms. Only non-vigorous infants born through MSAF included in randomised controlled trials, were included. We calculated overall relative risks (RRs) and mean differences with 95% CIs using a random-effects model, to determine the impact of ETS in non-vigorous infants born through MSAF.. The primary outcome was the incidence of meconium aspiration syndrome (MAS). Secondary outcomes were respiratory outcome measures (pneumothorax, persistent pulmonary hypertension of the newborn, secondary pneumonia, need for respiratory support, duration of mechanical ventilation), initial resuscitation and others including shock, perinatal asphyxia, convulsions, neonatal mortality, blood culture-positive sepsis and duration of hospital stay.. A total of 2085 articles were identified in the initial database search. Four studies, including 581 non-vigorous meconium-stained infants, fulfilled the inclusion criteria, comprising 292 infants in the non-ETS group and 289 in the ETS group. No statistically significant difference was found for MAS (RR 0.98; 95% CI 0.71 to 1.35).. Initiating ETS soon after birth in non-vigorous meconium-stained infants may not alter their neonatal outcomes.

Topics: Amniotic Fluid; Female; Humans; Infant, Newborn; Intubation, Intratracheal; Meconium; Meconium Aspiration Syndrome; Obstetric Labor Complications; Pregnancy; Randomized Controlled Trials as Topic; Respiratory Tract Diseases; Severity of Illness Index

The role of gastric lavage in neonates delivered through meconium-stained amniotic fluid remains unclear.. This study evaluated the effects of gastric lavage, compared to no gastric lavage, on the incidences of feeding intolerance, respiratory distress, meconium aspiration synd-rome, time to establish breastfeeding, hospitalization and pro-cedure-related complications in late-preterm and term neonates delivered through meconium-stained amniotic fluid.. Systematic review and meta-analysis.. MEDLINE, EMBASE, CENTRAL, and other databases were searched for randomized controlled trials and quasi-randomized controlled trials using search terms: neonate OR newborn infant, meconium OR meconium-stained amniotic fluid, and lavage OR gastric lavage from inception to May 2020. Data were pooled in RevMan and analyzed in GRADE.. Pooled effects (9 randomized controlled trials, number=3668), showed a significant reduction in the incidence of feeding intolerance (relative risk 0.70; 95% confidence interval 0.58,0.85, I2=0) after gastric lavage. No difference was observed for the incidence of meconium aspiration syndrome (4 studies) or procedure-related complications (7 studies). Only one study, reporting the proportion of neonates with low oxygenation (SpO2<85%), did not find any significant difference. No study evaluated the effects of gastric lavage on respiratory distress, breastfeeding, and hospitalization.. Low-quality evidence supported the role of gastric lavage for the prevention of feeding intolerance in late-preterm and term neonates born through meconium-stained amniotic fluid. Applicability of results was limited by the high risk of bias. Well-conducted randomized controlled trials with important patient outcomes are needed before recommending the practice of gastric lavage.

Topics: Amniotic Fluid; Gastric Lavage; Humans; Incidence; Infant; Infant, Newborn; Meconium; Meconium Aspiration Syndrome

The International Liaison Committee on Resuscitation sought to review the initial management of non-vigorous newborns delivered through meconium stained amniotic fluid (MSAF).. To complete a systematic review and meta-analysis comparing endotracheal intubation and suctioning to immediate resuscitation without intubation for non-vigorous infants born at ≥34 weeks gestation delivered through MSAF.. Medline, EMBASE, the Cochrane Database of Systematic Reviews, and other registries were searched from 1966 to November 7, 2019.. Studies were selected by pairs of independent reviewers in 2 stages.. Reviewers extracted data, appraised risk of bias, and assessed Grading of Recommendations Assessment, Development and Evaluation certainty of evidence for each outcome.. Four randomized controlled trials (RCTs) included 581 patients and one observational study included 231 patients. No significant differences were observed between the group treated with tracheal suctioning compared with immediate resuscitation for survival at discharge (4 RCTs; risk ratio [RR] = 1.01; 95 % CI, 0.96-1.06; p = 0.69; observational study; no deaths), hypoxic ischemic encephalopathy and meconium aspiration syndrome.. The certainty of evidence was low for survival at discharge and very low for all other outcomes.. For non-vigorous newborns delivered through MSAF, there is insufficient evidence to suggest routine immediate direct laryngoscopy with tracheal suctioning.. CRD42019122778.. PROSPERO; CRD42019122778.

Topics: Amniotic Fluid; Humans; Infant; Infant, Newborn; Intubation, Intratracheal; Meconium; Meconium Aspiration Syndrome; Observational Studies as Topic; Suction

Meconium-stained amniotic fluid (MSAF) during delivery is a marker of fetal stress. Neonates born through MSAF often need resuscitation and are at risk of meconium aspiration syndrome (MAS), air leaks, hypoxic-ischemic encephalopathy, extracorporeal membrane oxygenation (ECMO), and death. The neonatal resuscitation approach to MSAF has evolved over the last three decades. Previously, nonvigorous neonates soon after delivery were suctioned under the vocal cords with direct visualization technique using a meconium aspirator. The recent neonatal resuscitation program (NRP) recommends against suctioning but favors resuscitation with positive pressure ventilation of nonvigorous neonates with MSAF. This recommendation is aimed to prevent delay in resuscitation and minimize hypoxia-ischemia often associated with MSAF. In this review, we discuss the pathophysiology, evolution and the evidence, randomized control trials, observational studies, and translational research to support these recommendations. The frequency of ECMO use for neonatal respiratory indication of MAS has declined over the years probably secondary to improvements in neonatal intensive care and reduction of postmaturity. Changes in resuscitation practices may have contributed to reduced incidence and severity of MAS. Larger randomized controlled studies are needed among nonvigorous infants with MSAF. However, ethical dilemmas and loss of equipoise pose a challenge to conduct such studies.

Topics: Amniotic Fluid; Delivery Rooms; Evidence-Based Practice; Extracorporeal Membrane Oxygenation; Humans; Infant, Newborn; Intensive Care, Neonatal; Intubation, Intratracheal; Meconium; Meconium Aspiration Syndrome; Positive-Pressure Respiration; Practice Guidelines as Topic; Randomized Controlled Trials as Topic; Resuscitation; Suction

Approximately 1 in 10 pregnancies is affected by meconium passage at delivery, which can result in meconium aspiration syndrome (MAS). MAS can cause respiratory complications and, very rarely, death. Antibiotics have been prescribed for neonates exposed to meconium in amniotic fluid, with the intention of preventing infection due to potential bacterial contaminants.. We conducted this review to assess the efficacy and safety of antibiotics for:1. prevention of infection, morbidity, and mortality among infants born through meconium-stained amniotic fluid (MSAF) who are asymptomatic at birth; and2. prevention of infection, morbidity, and mortality among infants born through MSAF who have signs and symptoms compatible with meconium aspiration syndrome (MAS).. We performed a literature search using the following databases: MEDLINE (1966 to July 2016); Embase (1980 to July 2016); the Cumulative Index to Nursing and Allied Health Literature (CINAHL; 1982 to July 2016); and the Cochrane Central Register of Controlled Trials (CENTRAL; 2016, Issue 7) in the Cochrane Library. We also searched clinical trials databases, conference proceedings, and reference lists of retrieved articles.. We included randomised and quasi-randomised controlled trials that compared antibiotics administered via any route versus placebo or no treatment for prevention of infection among neonates exposed to MSAF, or who developed MAS. We excluded cohort, case control, and any other non-randomised studies and applied no language restrictions. We included studies of term and preterm infants, and we included studies examining use of any antibacterial antibiotics. We included studies that reported on any outcomes of interest.. We assessed the methodological quality of included trials by reviewing information provided in study reports and obtained by personal communication with study authors. We extracted data on relevant outcomes, estimated effect size, and reported values as risk ratios (RRs), risk differences (RDs), and mean differences (MDs), as appropriate. We conducted subgroup analyses for treatment of MAS and for prophylaxis (asymptomatic neonates exposed to meconium).. Four randomised controlled studies including a total of 695 participants were eligible for inclusion. Three studies evaluated neonates with MAS, and one study assessed asymptomatic neonates exposed to meconium in amniotic fluid. These studies exhibited varying degrees of methodological rigour: Two studies were at low risk of bias, and two were at unclear risk. We graded evidence derived from these studies as low quality. We downgraded overall evidence owing to the large number of participants lost to follow-up in one trial, the small sample sizes of all trials, and unclear methodological details provided for two trials.The primary outcome was risk of early- and late-onset neonatal sepsis. Antibiotics did not decrease the risk of sepsis in neonates with a diagnosis of MAS (RR 1.54, 95% confidence interval (CI) 0.27 to 8.96; RD 0.00, 95% CI -0.02 to 0.03; 445 participants, three studies; I² = 0%) nor in asymptomatic neonates exposed to meconium in amniotic fluid (RR 0.76, 95% CI 0.25 to 2.34; RD -0.01, 95% CI -0.07 to 0.04; 250 participants, one study; I² = 0%). Results show no significant differences in mortality or duration of stay in hospital between groups given antibiotics and control groups of symptomatic and asymptomatic neonates. One study in asymptomatic neonates reported a significant reduction in duration of mechanical ventilation for the control group compared with the antibiotic group (MD 0.26, 95% CI 0.15 to 0.37; 250 participants, one study; I² = 0%).. Upon review of available evidence, we found no differences in infection rates following antibiotic treatment among neonates born through meconium-stained fluid and those with meconium aspiration syndrome. The overall quality of evidence is low owing to the small number of included studies. Well-controlled studies of adequate power are needed.

Topics: Amikacin; Amniotic Fluid; Ampicillin; Anti-Bacterial Agents; Bacterial Infections; Gentamicins; Humans; Incidence; Infant, Newborn; Length of Stay; Meconium; Meconium Aspiration Syndrome; Neonatal Sepsis; Randomized Controlled Trials as Topic; Respiration, Artificial; Respiratory Insufficiency

In developing countries, meconium aspiration syndrome (MAS) is an important cause of morbidity and mortality among neonates. The concepts of pathophysiology and management of meconium stained amniotic fluid (MSAF) and meconium aspiration syndrome have undergone tremendous change in recent years. Routine intranatal and postnatal endotracheal suctioning of meconium in vigorous infants is no longer recommended. Recent studies have challenged its role even in non-vigorous infants. Supportive therapy like oxygen supplementation, mechanical ventilation and intravenous fluids are the cornerstone in the management of meconium aspiration syndrome. Availability of surfactant, inhaled nitric oxide, high frequency ventilators and extracorporeal membrane oxygenation has made it possible to salvage more infants with meconium aspiration syndrome. In this review the authors have discussed the current concepts in the pathophysiology and management of MAS. Drugs in trials and future therapeutic targets are also discussed briefly.

Topics: Humans; Infant, Newborn; Meconium; Meconium Aspiration Syndrome; Pulmonary Surfactants; Respiration, Artificial; Suction

Does meconium cause meconium aspiration syndrome (MAS) or is meconium discharge only a marker of fetal hypoxia? This dispute has lasted for centuries, but since the 1960s, detrimental effects of meconium itself on the lungs have been demonstrated in animal experiments. In clinical MAS, persistent pulmonary hypertension of the newborn is the leading cause of death in MAS. Regarding the complex chemical composition of meconium, it is difficult to identify a single agent responsible for the pathophysiology. However, considering that meconium is stored in the intestines, partly unexposed to the immune system, aspirated meconium could be recognized as ‘danger', representing damaged self. The common denominator in the pathophysiology could therefore be activation of innate immunity. Thus, a bulk of evidence implies that meconium is a potent activator of inflammatory mediators, including cytokines, complement, prostaglandins and reactive oxygen species. We hypothesize that the two main recognition systems of innate immunity, the Toll-like receptors and the complement system, recognize meconium as ‘danger', which leads not only to lung dysfunction but also to a systemic inflammatory response. This might have therapeutic implications in the future.

Topics: Animals; Complement Activation; Cytokines; Humans; Immunity, Innate; Infant, Newborn; Inflammation; Lung; Meconium; Meconium Aspiration Syndrome; Toll-Like Receptors

Amnioinfusion is thought to dilute meconium present in the amniotic fluid and so reduce the risk of meconium aspiration.. To assess the effects of amnioinfusion for meconium-stained liquor on perinatal outcome.. We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (1 December 2013).. Randomised trials comparing amnioinfusion with no amnioinfusion for women in labour with moderate or thick meconium staining of the amniotic fluid.. Three review authors independently assessed eligibility and trial quality, and extracted data.. Fourteen studies of variable quality (4435 women) are included.Subgroup analysis was performed for studies from settings with limited facilities to monitor the baby's condition during labour and intervene effectively, and settings with standard peripartum surveillance.Settings with standard peripartum surveillance: there was considerable heterogeneity for several outcomes. There was no significant reduction in the primary outcomes meconium aspiration syndrome, perinatal death or severe morbidity, and maternal death or severe morbidity. There was a reduction in caesarean sections (CSs) for fetal distress but not overall. Meconium below the vocal cords diagnosed by laryngoscopy was reduced, as was neonatal ventilation or neonatal intensive care unit admission, but there was no significant reduction in perinatal deaths or other morbidity. Planned sensitivity analysis excluding trials with greater risk of bias resulted in an absence of benefits for any of the outcomes studied.Settings with limited peripartum surveillance: three studies were included. In the amnioinfusion group there was a reduction in CS for fetal distress and overall; meconium aspiration syndrome (three studies, 1144 women; risk ratio (RR) 0.17, 95% confidence interval (CI) 0.05 to 0.52); perinatal mortality (three studies, 1151 women; RR 0.24, 95% CI 0.11 to 0.53) and neonatal ventilation or neonatal intensive care unit admission. In one of the studies, meconium below the vocal cords was reduced and, in the other, neonatal encephalopathy was reduced.. Amnioinfusion is associated with substantive improvements in perinatal outcome only in settings where facilities for perinatal surveillance are limited. It is not clear whether the benefits are due to dilution of meconium or relief of oligohydramnios.In settings with standard peripartum surveillance, some non-substantive outcomes were improved in the initial analysis, but sensitivity analysis excluding trials with greater risk of bias eliminated these differences. Amnioinfusion is either ineffective in this setting, or its effects are masked by other strategies to optimise neonatal outcome.The trials reviewed are too small to address the possibility of rare but serious maternal adverse effects of amnioinfusion.

Topics: Amnion; Cesarean Section; Female; Humans; Infant, Newborn; Injections; Meconium; Meconium Aspiration Syndrome; Obstetric Labor Complications; Perinatal Mortality; Pregnancy; Randomized Controlled Trials as Topic; Sodium Chloride

Meconium stained amniotic fluid (MSAF) is common and associated with meconium aspiration syndrome (MAS). Other consequences of meconium passage before birth are less well understood.. We reviewed the literature for original papers reporting on outcomes associated with MSAF.. Among preterm infants MSAF is more prevalent than previously believed and is associated with higher neonatal morbidity. Intrauterine exposure to meconium is associated with inflammation of tissues of the lung, chorionic plate and umbilical vessels and through various mechanisms may contribute to neonatal morbidity, independent of MAS. No compelling evidence supported an association between MSAF and increased neurological impairment, including early seizure activity.

Topics: Acidosis; Amniotic Fluid; Apgar Score; Asphyxia Neonatorum; Female; Fetus; Humans; Infant, Newborn; Infant, Premature; Meconium; Meconium Aspiration Syndrome; Otitis Media; Pregnancy; Seizures; Sepsis

Amnioinfusion is thought to dilute meconium present in the amniotic fluid and so reduce the risk of meconium aspiration.. To assess the effects of amnioinfusion for meconium-stained liquor on perinatal outcome.. We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (May 2009).. Randomised trials comparing amnioinfusion with no amnioinfusion for women in labour with moderate or thick meconium-staining of the amniotic fluid.. Two review authors assessed eligibility and trial quality, and extracted data, independently.. Thirteen studies of variable quality (4143 women) are included.Subgroup analysis was performed for studies from settings with limited facilities to monitor the baby's condition during labour and intervene effectively, and settings with standard peripartum surveillance.Settings with standard peripartum surveillance: there was considerable heterogeneity for several outcomes. There was no significant reduction in the primary outcomes meconium aspiration syndrome, perinatal death or severe morbidity, and maternal death or severe morbidity. There was a reduction in caesarean sections (CSs) for fetal distress but not overall. Meconium below the vocal cords diagnosed by laryngoscopy was reduced, as was neonatal ventilation or neonatal intensive care unit admission, but there was no significant reduction in perinatal deaths or other morbidity. Planned sensitivity analysis excluding trials with greater risk of bias resulted in an absence of benefits for any of the outcomes studied.Settings with limited peripartum surveillance: two studies (855 women) were included. In the amnioinfusion group there was a reduction in CS for fetal distress and overall; meconium aspiration syndrome (RR 0.25, 95% CI 0.13 to 0.47), and neonatal ventilation or neonatal intensive care unit admission; and a trend towards reduced perinatal mortality (RR 0.37, 95% CI 0.13 to 1.01). In one of the studies, meconium below the vocal cords was reduced and, in the other, neonatal encephalopathy was reduced.. Amnioinfusion is associated with substantive improvements in perinatal outcome only in settings where facilities for perinatal surveillance are limited. It is not clear whether the benefits are due to dilution of meconium or relief of oligohydramnios.In settings with standard peripartum surveillance, some non-substantive outcomes were improved in the initial analysis, but sensitivity analysis excluding trials with greater risk of bias eliminated these differences. Amnioinfusion is either ineffective in this setting, or its effects are masked by other strategies to optimise neonatal outcome.The trials reviewed are too small to address the possibility of rare but serious maternal adverse effects of amnioinfusion.

Topics: Amnion; Female; Humans; Infant, Newborn; Injections; Meconium; Meconium Aspiration Syndrome; Obstetric Labor Complications; Pregnancy; Randomized Controlled Trials as Topic

Amnioinfusion aims to prevent or relieve umbilical cord compression during labour by infusing a solution into the uterine cavity. It is also thought to dilute meconium when present in the amniotic fluid and so reduce the risk of meconium aspiration. However, it may be that the mechanism of effect is that it corrects oligohydramnios (reduced amniotic fluid), for which thick meconium staining is a marker.. The objective of this review was to assess the effects of amnioinfusion for meconium-stained liquor on perinatal outcome.. The Cochrane Pregnancy and Childbirth Group trials register (October 2001) and the Cochrane Controlled Trials Register (Issue 3, 2001) were searched.. Randomised trials comparing amnioinfusion with no amnioinfusion for women in labour with moderate or thick meconium-staining of the amniotic fluid.. Eligibility and trial quality were assessed by one reviewer.. Twelve studies, most involving small numbers of participants, were included. Under standard perinatal surveillance, amnioinfusion was associated with a reduction in the following: heavy meconium staining of the liquor (relative risk 0.03, 95% confidence interval 0.01 to 0.15); variable fetal heart rate deceleration (relative risk 0.65, 95% confidence interval 0.49 to 0.88); and reduced caesarean section overall (relative risk 0.82, 95% confidence interval 0.69 to 1.97). No perinatal deaths were reported. Under limited perinatal surveillance, amnioinfusion was associated with a reduction in the following: meconium aspiration syndrome (relative risk 0.24, 95% confidence interval 0.12 to 0.48); neonatal hypoxic ischaemic encephalopathy (relative risk 0.07, 95% confidence interval 0.01 to 0.56) and neonatal ventilation or intensive care unit admission (relative risk 0.56, 95% confidence interval 0.39 to 0.79); there was a trend towards reduced perinatal mortality (relative risk 0.34, 95% confidence interval 0.11 to 1.06).. Amnioinfusion is associated with improvements in perinatal outcome, particularly in settings where facilities for perinatal surveillance are limited. The trials reviewed are too small to address the possibility of rare but serious maternal adverse effects of amnioinfusion.

Topics: Amnion; Female; Humans; Infant, Newborn; Injections; Meconium; Meconium Aspiration Syndrome; Obstetric Labor Complications; Pregnancy; Randomized Controlled Trials as Topic

Meconium-stained amniotic fluid is a common occurrence which places the mother at risk of escalating obstetric interventions, and the baby at risk of meconium aspiration syndrome.. The Cochrane Library was searched for interventions related to care before delivery with useful evidence on the outcomes 'meconium-stained amniotic fluid' and 'meconium aspiration syndrome'.. Curtailment of post-term pregnancy reduces the occurrence of meconium-stained amniotic fluid, and meconium aspiration syndrome. Uterine stimulants, particularly misoprostol, are associated with occurrence of meconium-stained amniotic fluid. Amniotomy during labour may be a risk factor for meconium aspiration syndrome. There is little research evidence on the benefits or otherwise of obstetric interventions such as expedited delivery for meconium-stained liquor without other evidence of fetal distress. Amnioinfusion for meconium-stained amniotic fluid improves neonatal outcome only in settings with limited peripartum surveillance. There is insufficient evidence to support the use of amnioinfusion for meconium-stained liquor in settings with adequate peripartum surveillance.

Topics: Amnion; Delivery, Obstetric; Female; Fetus; Humans; Infant, Newborn; Labor, Induced; Meconium; Meconium Aspiration Syndrome; Pregnancy

To review current literature related to cellular mechanisms of meconium-induced lung injury (MILI). Review of published experimental in vitro and in vivo MAS studies using human and animal lung cells. We found that meconium induces expression of cytokines and angiotensin II (ANG II)-induced apoptotic process in the lung cells. We postulate that inflammatory cytokines induce ANG II expression, which causes apoptotic cell death after binding to its AT1 receptors. We also demonstrated expression of serpins associated with meconium instillation into the lungs. Serpins are proteins that inhibit cellular proteases and elastases. Expression of serpins may be an attempt to recover lung from these injurious effects. In summary our studies show that whereas meconium induces inflammatory cytokines and subsequent cell apoptosis, the lung cells also try to protect themselves by inducing serpins. The balance of these interactions will determine the residual damage. We believe these new findings are very important in understanding of MILI.

Topics: Angiotensin II; Animals; Apoptosis; Cytokines; Humans; Infant, Newborn; Lung; Meconium; Meconium Aspiration Syndrome; Serpins

Although the triggering mechanisms of tissue inflammation and injury in meconium-contaminated lungs are still unclear, there is increasing evidence to suggest a central role for phospholipase A(2)'s (PLA(2)). In fact, elevated PLA(2) activities together with high enzyme concentrations, especially the amount of pancreatic (group I) secretory PLA(2) (PLA(2)-I), have been detected in human meconium and in meconium-contaminated lungs. Recent data from our laboratory further indicate that human pancreatic PLA(2), introduced in high amounts within aspirated particulate meconium, is a potent inducer of lung tissue inflammatory injury. Our finding of elevated human PLA(2)-I concentrations in plasma during the first hours after intratracheal meconium administration in newborn piglets further suggests that intrapulmonary aspiration of meconium could also have systemic inflammatory and injurious effects. This, however, remains to be studied in further detail.

Topics: Humans; Infant, Newborn; Lung Injury; Meconium; Meconium Aspiration Syndrome; Phospholipases A2

Review of all medical literature dealing with delivery room management of meconium-stained infants. Additionally, the author contacted multiple individuals involved historically or clinically with the published studies or the persons who developed treatment guidelines. Although many therapies have been suggested as being effective, none have been definitively proven efficacious by the gold standard: a large, randomized, controlled trial (RCT). Further adequate investigations (RCTs) need to be performed to assess whether proposed management schemes are of benefit in the care of meconium-stained newborn infants.

Topics: Amniotic Fluid; Delivery Rooms; Humans; Infant, Newborn; Intubation, Intratracheal; Meconium; Meconium Aspiration Syndrome

The meconium aspiration syndrome (MAS) is a common problem that continues to concern perinatologists and neonatologists. MAS is defined as respiratory distress in an infant born through meconium-stained amniotic fluid (MSAF) whose symptoms cannot be otherwise explained. This disorder may be life threatening, complicated by respiratory failure, pulmonary air leaks and persistent pulmonary hypertension. Approaches to the prevention of MAS have changed over time with collaboration between obstetricians and pediatricians forming the foundations for care. This report details the management of babies delivered with associated MSAF before the accumulation of evidence for best practice through appropriately powered, prospective randomized controlled trials.

Topics: Amniotic Fluid; Evidence-Based Medicine; Extracorporeal Membrane Oxygenation; Glucocorticoids; Humans; Hypertension, Pulmonary; Infant, Newborn; Meconium; Meconium Aspiration Syndrome

Routine oronasopharyngeal suctioning (ONPS) of the infant at delivery is a common practice in the delivery room. ONPS is performed to remove lung fluid, meconium, or other secretions from the airway, thereby improving oxygenation and/or preventing aspiration. However, there are controversies regarding this practice, as it seems to be associated with complications. In the presence of clear amniotic fluid, routine ONPS in infants born vaginally and by cesarean section is associated with bradycardia, apnea, and delays in achieving normal oxygen saturations, with no benefit. Intrapartum ONPS and post-natal endotracheal suctioning of vigorous infants born through meconium-stained amniotic fluid (MSAF) does not prevent meconium aspiration syndrome (MAS). Although depressed infants born through MSAF are at risk of developing MAS, there is no evidence that endotracheal suctioning of these infants reduces MAS.

Topics: Humans; Infant, Newborn; Meconium; Meconium Aspiration Syndrome; Oxygen; Parturition; Perineum; Suction

Since a decade, some studies had discussed preventive and curative treatment of infants born to mothers with meconium-stained amniotic fluid. Today amnio-infusion, formerly proposed, is reconsidered in countries where midwives and obstetricians carefully monitor the fetal heart rate tracing during labor. Actually routine intrapartum oropharyngeal and nasopharyngeal suctioning, before and after shoulders delivery, followed by tracheal suction, are not recommended for infants born to mothers with meconium stained amniotic fluid.

Topics: Amniotic Fluid; Female; Humans; Infant, Newborn; Meconium; Meconium Aspiration Syndrome; Obstetric Labor Complications; Pregnancy; Suction

The article reviews and critically evaluates the available evidence to determine whether the current recommendations for the management of infants born through meconium stained amniotic fluid (MSAF) should be maintained. Authors provide evidence-based recommendations regarding the benefits of amnioinfusion prior to delivery, oral suctioning of the newborn prior to delivery of the shoulder, and the practice of routine endotracheal suctioning of the newborn born through MSAF in preventing meconium aspiration syndrome (MAS). Authors also discuss the gaps in knowledge in all the above interventions to prevent MAS.

Topics: Amnion; Amniotic Fluid; Evidence-Based Medicine; Female; Humans; Infant, Newborn; Infusions, Parenteral; Intubation, Intratracheal; Meconium; Meconium Aspiration Syndrome; Postpartum Period; Pregnancy; Sodium Chloride; Suction

Meconium passage in newborn infants is a developmentally programmed event normally occurring within the first 24 to 48 hours after birth. Intrauterine meconium passage in near-term or term fetuses has been associated with fetomaternal stress factors and/or infection, whereas meconium passage in postterm pregnancies has been attributed to gastrointestinal maturation. Despite these clinical impressions, little information is available on the mechanism(s) underlying the normal meconium passage that occurs immediately after birth or during the intrauterine period of fetal development. Birth itself is a stressful process and it is possible that fetal stress-mediated biochemical events may regulate the meconium passage occurring either during labor or after birth. Aspiration of meconium during intrauterine life may result in or contribute to meconium aspiration syndrome (MAS), representing a continued leading cause of perinatal death. This article reviews aspects of meconium passage in utero, its consequences, and management.

Topics: Adult; Digestive System; Female; Fetal Death; Fetal Development; Fetal Distress; Humans; Infant, Newborn; Meconium; Meconium Aspiration Syndrome; Obstetrics; Parturition; Pregnancy; Pregnancy Outcome; Risk Factors; Syndrome

Amnioinfusion aims to prevent or relieve umbilical cord compression during labour by infusing a solution into the uterine cavity. It is also thought to dilute meconium when present in the amniotic fluid and so reduce the risk of meconium aspiration. However, it may be that the mechanism of effect is that it corrects oligohydramnios (reduced amniotic fluid), for which thick meconium staining is a marker.. The objective of this review was to assess the effects of amnioinfusion for meconium-stained liquor on perinatal outcome.. The Cochrane Pregnancy and Childbirth Group trials register (October 2001) and the Cochrane Controlled Trials Register (Issue 3, 2001) were searched.. Randomised trials comparing amnioinfusion with no amnioinfusion for women in labour with moderate or thick meconium-staining of the amniotic fluid.. Eligibility and trial quality were assessed by one reviewer.. Twelve studies, most involving small numbers of participants, were included. Under standard perinatal surveillance, amnioinfusion was associated with a reduction in the following: heavy meconium staining of the liquor (relative risk 0.03, 95% confidence interval 0.01 to 0.15); variable fetal heart rate deceleration (relative risk 0.65, 95% confidence interval 0.49 to 0.88); and reduced caesarean section overall (relative risk 0.82, 95% confidence interval 0.69 to 1.97). No perinatal deaths were reported. Under limited perinatal surveillance, amnioinfusion was associated with a reduction in the following: meconium aspiration syndrome (relative risk 0.24, 95% confidence interval 0.12 to 0.48); neonatal hypoxic ischaemic encephalopathy (relative risk 0.07, 95% confidence interval 0.01 to 0.56) and neonatal ventilation or intensive care unit admission (relative risk 0.56, 95% confidence interval 0.39 to 0.79); there was a trend towards reduced perinatal mortality (relative risk 0.34, 95% confidence interval 0.11 to 1.06).. Amnioinfusion is associated with improvements in perinatal outcome, particularly in settings where facilities for perinatal surveillance are limited. The trials reviewed are too small to address the possibility of rare but serious maternal adverse effects of amnioinfusion.

Topics: Amnion; Female; Humans; Infant, Newborn; Injections; Meconium; Meconium Aspiration Syndrome; Obstetric Labor Complications; Pregnancy; Randomized Controlled Trials as Topic

For many years early systematic intubation and tracheal suction have been advocated for meconium-stained infants. Recent data show that they do not reduce the frequency of pulmonary meconium aspiration and underline the importance of a preventive attitude (i.e., intrapartum oropharyngeal suction before shoulder clearing and thoracic compression before first breathing) together with a selective tracheal suction only in the newborns with obvious oropharyngeal meconial staining.

Topics: Algorithms; Amniotic Fluid; Decision Trees; Delivery, Obstetric; Humans; Infant, Newborn; Intubation, Intratracheal; Meconium; Meconium Aspiration Syndrome; Perinatal Care; Suction

Amnioinfusion aims to prevent or relieve umbilical cord compression during labour by infusing a solution into the uterine cavity. It is also thought to dilute meconium when present in the amniotic fluid and so reduce the risk of meconium aspiration. However it may be that the mechanism of effect is that it corrects oligohydramnios (reduced amniotic fluid), for which thick meconium staining is a marker.. The objective of this review was to assess the effects of amnioinfusion for meconium-stained liquor on perinatal outcome.. The Cochrane Pregnancy and Childbirth Group trials register and the Cochrane Controlled Trials Register were searched.. Randomised trials comparing amnioinfusion with no amnioinfusion for women in labour with moderate or thick meconium-staining of the amniotic fluid.. Eligibility and trial quality were assessed by one reviewer.. Ten studies, most involving small numbers of participants, were included. Under standard perinatal surveillance, amnioinfusion was associated with a reduction in the following: heavy meconium staining of the liquor (relative risk 0.03, 95% confidence interval 0.01 to 0.15); variable fetal heart rate deceleration (relative risk 0.47, 95% confidence interval 0.24 to 0. 90); and a trend to reduced caesarean section overall (relative risk 0.83, 95% confidence interval 0.69 to 1.00). No perinatal deaths were reported. Under limited perinatal surveillance, amnioinfusion was associated with a reduction in the following: meconium aspiration syndrome (relative risk 0.24, 95% confidence interval 0. 12 to 0.48); neonatal hypoxic ischaemic encephalopathy (relative risk 0.07, 95% confidence interval 0.01 to 0.56) and neonatal ventilation or intensive care unit admission (relative risk 0.56, 95% confidence interval 0.39 to 0.79); there was a trend towards reduced perinatal mortality (relative risk 0.34, 95% confidence interval 0.11 to 1.06).. Amnioinfusion is associated with improvements in perinatal outcome, particularly in settings where facilities for perinatal surveillance are limited. The trials reviewed are too small to address the possibility of rare but serious maternal adverse effects of amnioinfusion.

Topics: Amnion; Female; Humans; Infant, Newborn; Injections; Meconium; Meconium Aspiration Syndrome; Obstetric Labor Complications; Pregnancy

Meconium staining of the amniotic fluid in labor is a frequent problem that is associated with an increase in the risk of neonatal and maternal morbidity. Amnioinfusion is a simple technique that is designed to prevent neonatal and maternal morbidity associated with meconium. Preliminary studies indicate that amnioinfusion is a promising approach to the prevention of such complications of labor. However, further research is required. The primary objective of this multi-centre randomized controlled study is to determine if amnioinfusion for thick meconium stained amniotic fluid results in a reduction in perinatal death or moderate to severe meconium aspiration syndrome. We will also assess the effects of amnioinfusion on other indicators of neonatal morbidity and on cesarean section. The study includes an evaluation of womens views on their childbirth experience and an economic evaluation of a policy of amnioinfusion The study will be achieved with the collaboration of approximately 50 obstetrical centres from across Canada, US, Europe, South America and South Africa. This multicentre trial will provide urgently needed information on the efficacy and effectiveness of amniofusion for the indication of meconium stained amniotic fluid.

Topics: Amniotic Fluid; Humans; Infant, Newborn; Infant, Newborn, Diseases; Meconium; Meconium Aspiration Syndrome; Multicenter Studies as Topic; Patient Selection; Randomized Controlled Trials as Topic

To evaluate the effectiveness of intrapartum prophylactic amnioinfusion in pregnancies complicated by meconium-stained amniotic fluid.. We identified prospective clinical trials of amnioinfusion in pregnancies complicated by meconium-stained amniotic fluid (AF) published in English by using computerized databases, references in published studies, and index reviews.. We analyzed prospective studies of intrapartum amnioinfusion for meconium-stained AF. In every case, group allocation was based exclusively on meconium in AF. Only published studies with clearly documented outcome data were included. The trials were evaluated for meconium below the vocal cords, meconium aspiration syndrome, fetal acidemia, cesarean delivery, and postpartum endometritis. Each trial was evaluated for the quality of its methodology, inclusion and exclusion criteria, adequacy of randomization, amnioinfusion protocols, definition of outcomes, and statistical analyses.. Thirteen studies met inclusion criteria for our systematic review. Odds ratios (ORs) with their 95% confidence intervals (CIs) were calculated for each outcome. Estimates of ORs and risk differences for dichotomous outcomes were calculated using random and fixed-effects models. We tested for homogeneity across the studies. We found that intrapartum amnioinfusion significantly reduced the frequency of meconium aspiration syndrome (OR 0.30; 95% CI 0.19, 0. 46), of meconium below the vocal cords, and neonatal acidemia. Subjects allocated to receive amnioinfusion also had a significantly lower overall cesarean rate (OR 0.74, 95% CI 0.59, 0.93) without increased postpartum endometritis.. Amnioinfusion in cases of meconium-stained fluid significantly improves neonatal outcome, lowers the cesarean delivery rate, and does not increase the postpartum endometritis rate.

Topics: Amnion; Amniotic Fluid; Cesarean Section; Clinical Trials as Topic; Female; Humans; Infant, Newborn; Meconium; Meconium Aspiration Syndrome; Obstetric Labor Complications; Pregnancy; Prospective Studies

Meconium-stained amniotic fluid might signify underlying acute or chronic fetal hypoxia with adverse perinatal outcome, especially if associated with cardiotocographic abnormality. Management requires awareness of this potential risk, appropriate intrapartum care and a combined obstetricneonatal approach. Amnioinfusion can be an effective preventative measure.

Topics: Administration, Intravaginal; Algorithms; Amniotic Fluid; Female; Fetal Distress; Humans; Infant, Newborn; Infusions, Parenteral; Meconium; Meconium Aspiration Syndrome; Obstetric Labor Complications; Pregnancy; Randomized Controlled Trials as Topic

Meconium staining of the amniotic fluid will always be a common problem. Although several therapies may be of benefit in preventing MAS, most require further rigorous scientific investigation to assess their potential in preventing this disorder.

Topics: Amniotic Fluid; Delivery Rooms; Delivery, Obstetric; Humans; Infant, Newborn; Intubation, Intratracheal; Meconium; Meconium Aspiration Syndrome; Risk Factors; Suction

Over the past 5 years, increasing understanding about the pathophysiology of meconium-stained amniotic fluid (MSAF) and the meconium aspiration syndrome (MAS) has occurred. Many new therapies are being used in an attempt to prevent MAS and to treat the disorder. The authors review the current status of knowledge concerning the MSAF and MAS and management of these entities.

Topics: Amniotic Fluid; Chorioamnionitis; Female; Humans; Infant, Newborn; Inflammation; Intensive Care, Neonatal; Meconium; Meconium Aspiration Syndrome; Pregnancy; Pregnancy Outcome; Respiratory Distress Syndrome, Newborn

Meconium staining of the amniotic fluid and the meconium aspiration syndrome will likely remain common occurrences faced by health care providers. Unfortunately, our understanding of these entities is incomplete. There are a number of issues which need to be adequately evaluated regarding the pathophysiology of MAS, the delivery room management of the meconium-stained infant, and the neonatal intensive care unit management of MAS. Currently, there is much dogma in various hospitals throughout this country regarding these issues, dogma which has yet to be substantiated by quality scientific investigations.

Topics: Humans; Infant, Newborn; Intubation, Intratracheal; Meconium; Meconium Aspiration Syndrome; Pulmonary Surfactants; Respiration, Artificial; Suction

Meconium-stained amniotic fluid occurs in approximately 12% of live births. In approximately one third of these infants meconium is present below the vocal cords. However, meconium aspiration syndrome develops in only 2 of every 1000 live-born infants. Ninety-five percent of infants with inhaled meconium clear the lungs spontaneously. Recent investigations have suggested that a reexamination of our assumptions about the etiology of meconium aspiration syndrome is in order. Several authors have provided evidence that support the hypothesis that it is not the inhaled meconium which produces the primary pathologic condition of meconium aspiration syndrome but rather it is fetal asphyxia that is the etiologic agent. Asphyxia in utero produces pulmonary vasospasm and hyperreactivity of the pulmonary vessels. With severe asphyxia the fetal lungs undergo pulmonary vascular damage with pulmonary hypertension. The damaged lungs are then unable to clear the meconium. In the most severe cases there is right-to-left shunting and persistent fetal circulation with subsequent fetal death. The incidence of meconium aspiration may thus be essentially unaffected by current obstetric and pediatric interventions at birth. For the asphyxiated or distressed infant we recommend suctioning at birth and tracheal intubation. In the healthy fetus observation may be sufficient.

Topics: Asphyxia Neonatorum; Fetal Distress; Humans; Infant, Newborn; Meconium; Meconium Aspiration Syndrome; Respiratory Insufficiency; Syndrome

The pathogenesis of meconium passage and the pathophysiology of meconium aspiration are reviewed. Intrapartum and neonatal strategies for the prevention of meconium aspiration syndrome are presented in historical perspective, and newer interventions are appraised.

Topics: Amniotic Fluid; Delivery, Obstetric; Female; Fetal Distress; Humans; Infant Care; Infant, Newborn; Meconium; Meconium Aspiration Syndrome; Pregnancy

Our objective was to study the strength of the association between meconium-stained amniotic fluid and severe morbidity among neonates of nulliparas with prolonged pregnancies.. This was a secondary analysis of the NOCETER randomized trial that took place between 2009 and 2012 in which 11 French maternity units included 1373 nulliparas at 41. This study included 1274 patients: 803 (63%) in the group with normal amniotic fluid, 196 (15.4%) in the thin amniotic fluid group, and 275 (21.6%) in the thick amniotic fluid group. The neonates of patients with thick amniotic fluid had higher rates of neonatal morbidity than those of patients with normal amniotic fluid (7.3% vs. 2.2%; p < 0.001; adjusted relative risk [aRR] 3.3, 95% confidence interval [CI] 1.7-6.3), but those of patients with thin amniotic fluid did not (3.1% vs. 2.2%; p = 0.50; aRR 1.0, 95% CI, 0.4-2.7).. Among nulliparas at 41

Topics: Amniotic Fluid; Female; Humans; Infant, Newborn; Infant, Newborn, Diseases; Meconium; Meconium Aspiration Syndrome; Obstetric Labor Complications; Pregnancy; Pregnancy Complications; Pregnancy, Prolonged

Topics: Female; Helium; Humans; Infant; Infant, Newborn; Meconium; Meconium Aspiration Syndrome; Oxygen

Tracheal suctioning in non-vigorous newborn delivered through meconium-stained amniotic fluid (MSAF) is supposed to delay initiation of positive pressure ventilation (PPV), but the magnitude of such delay is unknown. To compare the time of PPV initiation when performing immediate laryngoscopy with intubation and suctioning vs. performing immediate PPV without intubation in a manikin model. Randomized controlled crossover (AB/BA) trial comparing PPV initiation with or without endotracheal suctioning in a manikin model of non-vigorous neonates born through MSAF. Participants were 20 neonatologists and 20 pediatric residents trained in advanced airway management. Timing of PPV initiation was longer with vs. without endotracheal suctioning in both pediatric residents (mean difference 13 s, 95% confidence interval 8 to 18 s; p < 0.0001) and neonatologists (mean difference 12 s, 95% confidence interval 8 to 16 s; p < 0.0001). The difference in timing of PPV initiation was similar between pediatric residents and neonatologists (mean difference - 1 s, 95% confidence interval - 7 to 6 s; p = 0.85).Conclusions: Performing immediate laryngoscopy with intubation and suctioning was associated with longer-but not clinically relevant-time of initiation of PPV compared with immediate PPV without intubation in a manikin model. While suggesting negligible delay in starting PPV, further studies in a clinical setting are warranted.Registration: clinicaltrial.gov NCT04076189. What is Known: • Management of the non-vigorous newborn delivered through meconium-stained amniotic fluid remains still controversial. • Tracheal suctioning in non-vigorous newborn delivered through meconium-stained amniotic fluid is supposed to delay initiation of positive pressure ventilation, but the magnitude of such delay is unknown. What is New: • Performing immediate ventilation without intubation was associated with shorter-but not clinically relevant-time of initiation of ventilation compared to immediate laryngoscopy with intubation and suctioning in a manikin model. • Further studies in a clinical setting are warranted.

Topics: Child; Cross-Over Studies; Humans; Infant, Newborn; Intubation, Intratracheal; Manikins; Meconium; Meconium Aspiration Syndrome; Positive-Pressure Respiration; Suction

To compare the incidence of meconium aspiration syndrome and feed intolerance in infants born through meconium stained amniotic fluid with or without gastric lavage performed at birth.. Neonatal unit of a teaching hospital in New Delhi, India.. Parallel group unmasked randomized controlled trial.. 700 vigorous infants of gestational age ≥34 weeks from through meconium stained amniotic fluid.. Gastric lavage in the labor room with normal saline at 10 mL per kg body weight (n=350) or no gastric lavage (n=350). Meconiumcrit was measured and expressed as ≤30% and >30%.. Meconium aspiration syndrome, feed intolerance and procedure-related complications during 72 h of observation.. 5 (1.4%) infants in lavage group and 8 (2.2%) in no lavage group developed meconium aspiration syndrome (RR 0.63, 95% CI 0.21, 1.89). Feed intolerance was observed in 37 (10.5%) and 53 infants (15.1%) in lavage and no lavage groups, respectively (RR 0.70, 95% CI 0.47, 1.03). None of the infants in either group developed apnea, bradycardia or cyanosis during the procedure.. Gastric lavage performed in the labor room does not seem to reduce either meconium aspiration syndrome or feed intolerance in vigorous infants born through meconium stained amniotic fluid.

Topics: Amniotic Fluid; Female; Gastric Lavage; Humans; Infant, Newborn; Male; Meconium; Meconium Aspiration Syndrome; Vomiting

The objective of the study was to evaluate the effect of administering prophylactic antibiotics on the development of neonatal sepsis in term neonates born through meconium-stained amniotic fluid (MSAF). Two hundred and fifty eligible neonates were randomized to study group (Antibiotic group-receiving first-line antibiotics for 3 days) and control group (No Antibiotic group). Both groups were evaluated clinically and by laboratory parameters (sepsis screen and blood cultures) for development of sepsis. All neonates were monitored for respiratory, neurological, and other systemic complications and received supportive treatment according to standard management protocol of the unit. One hundred and twenty one neonates were randomized to 'Antibiotic' group and 129 to 'No Antibiotic' group. The overall incidence of suspect sepsis was 9.6 % in the study population with no significant difference between 'No Antibiotic' and 'Antibiotic' groups (10.8 vs. 8.2 %, p = 0.48, odds ratio (OR) 0.74, 95 % confidence interval (CI) 0.32-1.73). Incidence of culture-proven sepsis was also not significantly different between the two groups (5.42 vs. 4.13 %, p = 0.63, OR 0.75, 95 % CI 0.23-2.43). The incidence of mortality, meconium aspiration syndrome, and other complications was comparable amongst the two groups.. Routine antibiotic prophylaxis in neonates born through MSAF did not reduce the incidence of sepsis in this study population. (Clinicaltrials.gov no. - NCT01290003).

Topics: Amikacin; Amniotic Fluid; Anti-Bacterial Agents; Antibiotic Prophylaxis; Double-Blind Method; Female; Humans; Infant, Newborn; Infusions, Intravenous; Male; Meconium; Meconium Aspiration Syndrome; Penicillanic Acid; Piperacillin; Piperacillin, Tazobactam Drug Combination; Pregnancy; Prospective Studies; Sepsis

To assess whether endotracheal suctioning of nonvigorous infants born through meconium stained amniotic fluid (MSAF) reduces the risk and complications of meconium aspiration syndrome (MAS).. Term, nonvigorous babies born through MSAF were randomized to endotracheal suction and no-suction groups (n=61 in each). Risk of MAS, complications of MAS and endotracheal suction, mortality, duration of neonatal intensive care unit stay, and neurodevelopmental outcome at 9 months were assessed.. Maternal age, consistency of meconium, mode of delivery, birth weight, sex, and Apgar scores were similar in the groups. In total, 39 (32%) neonates developed MAS and 18 (14.8%) of them died. There were no significant differences in MAS, its severity and complications, mortality, and neurodevelopmental outcome for the 2 groups. One infant had a complication of endotracheal suctioning, which was mild and transient.. The current practice of routine endotracheal suctioning for nonvigorous neonates born through MSAF should be further evaluated.. Clinical Trial Registry of India: CTRI/2013/03/003469.

Topics: Amniotic Fluid; Apgar Score; Birth Weight; Delivery, Obstetric; Female; Humans; Infant; Infant, Newborn; Intensive Care Units, Neonatal; Intensive Care, Neonatal; Intubation, Intratracheal; Male; Meconium; Meconium Aspiration Syndrome; Suction

The role of gastric lavage in preventing retching, vomiting and secondary meconium aspiration syndrome in neonates with meconium-stained amniotic fluid is uncertain, and no there are no definitive guidelines.. To evaluate the effect of gastric lavage in preventing retching, vomiting and secondary meconium aspiration syndrome in neonates with meconium-stained amniotic fluid.. This was an open-label, parallel, randomized controlled trial conducted in the labour room, postnatal and neonatal wards of a tertiary-care teaching hospital. Vigorous neonates of ≧34 weeks gestation with meconium-stained amniotic fluid were randomised into two groups using block randomisation. Infants requiring oxygen, in respiratory distress or with major congenital malformations were excluded. Infants in the study group received elective gastric lavage in the labour room after initial stabilisation. No gastric lavage was done in the control group. The newborns were assessed for retching, vomiting and secondary meconium aspiration syndrome in the first 48 hrs of life or until discharge from the hospital, whichever was later.. A total of 267 newborns were randomly assigned to the gastric lavage group and 269 to the no gastric lavage group. There were no statistical differences in overall feeding between the two groups (6·74% vs 10·78%). Feeding of two newborns in the no-lavage group had to be omitted for the initial few hours because of vomiting; this did not happen in any newborn in the lavage group. No newborn in either group developed secondary meconium aspiration syndrome.. Gastric lavage in newborns with meconium-stained amniotic fluid does not prevent or reduce the occurrence of feeding problems or secondary meconium aspiration syndrome.

Topics: Amniotic Fluid; Female; Gastric Lavage; Hospitals, Teaching; Humans; Infant, Newborn; Male; Meconium; Meconium Aspiration Syndrome; Pregnancy; Tertiary Care Centers; Treatment Outcome

The purpose of our study was to evaluate the safety and efficacy of transcervical amnioinfusion during labour complicated by meconium-stained amniotic fluid, in a setting with limited peripartum facilities, to lower the incidence of caesarean section.. A prospective study was conducted in a teaching hospital in north India, which enrolled 292 patients admitted in labour. Patients were randomly divided into two groups after taking their consent. One group received transcervical amnioinfusion, whilst in the other group amnioinfusion was not done. Caesarean sections were performed in either group if there were foetal heart rate abnormalities (bradycardia or irregularity for 10-20 min) or slow progress of labour. The outcomes studied were the incidence of caesarean sections, duration of maternal hospital stay, maternal febrile morbidity (temperature of >38 degrees C, 24 h after delivery), low Apgar score (at 1 and 5 min), respiratory death, MAS and perinatal mortality.. There was a statistically significant reduction in the incidence of caesarean sections in the study group compared to the control group (31 vs. 61%). Amnioinfusion was associated with improved neonatal outcome as evidenced by statistically improved Apgar score at 1 min in newborns in the study group compared to the control group (10 vs. 37.2%). Amnioinfusion during labour was not associated with any significant maternal and neonatal complications. The mean hospital stay of the mother was decreased significantly in the study group patients compared to the control group.. Transcervical amnioinfusion in labour for meconium-stained amniotic fluid is a simple, safe and easy-to-perform procedure. It can be performed safely in a setup with limited peripartum facilities, especially in developing countries, to decrease intrapartum operative intervention and reduce foetomaternal morbidity and mortality.

Topics: Adolescent; Adult; Amnion; Apgar Score; Cesarean Section; Female; Fetal Distress; Fever; Hospitals, Teaching; Humans; Incidence; India; Infant Mortality; Infant, Newborn; Infusions, Parenteral; Length of Stay; Meconium; Meconium Aspiration Syndrome; Obstetric Labor Complications; Pregnancy; Pregnancy Outcome; Prospective Studies; Young Adult

To assess the rates of cesarean deliveries and perinatal outcome following intrapartum transcervical amnioinfusion in women with meconium-stained amniotic fluid (MSAF) in a setting with no electronic fetal monitoring or specialized neonatal care.. In this prospective comparative study with 150 women who were in labor and had MSAF, 50 of the women received a transcervical amnioinfusion and the remaining 100 women received standard care. The inclusion criteria were a pregnancy of at least 37 weeks' duration, a single live fetus in cephalic presentation, no major medical or obstetric complications, and no known fetal malformation. The amnioinfusion was performed with 1000 mL of normal saline solution through a red rubber catheter.. Amnioinfusion was associated with a significant decrease in the incidence of low Apgar score (<7) at 1 min (12% vs. 47%; relative risk [RR], 0.26; 95% confidence interval [CI], 0.12-0.56); low Apgar score at 5 min (4% vs. 23%; RR, 0.17; 95% CI, 0.04-0.71); and meconium aspiration syndrome (4% vs. 18%; RR, 0.22; 95% CI, 0.05-0.92). There was also a trend towards a lesser incidence of cesarean deliveries (18% vs. 30%; RR, 0.6; 95% CI, 0.31-1.16) and perinatal deaths (4% vs. 13%; RR, 0.31; 95% CI, 0.07-1.31). The incidence of maternal hospital stays longer than 3 days was significantly lower in the amnioinfusion than in the control group (24% vs. 48%; RR, 0.5; 95% CI, 0.29-0.85). There were no major complications related to amnioinfusion.. Intrapartum amnioinfusion for MSAF is a simple, safe, effective, and inexpensive procedure feasible in settings where intrapartum monitoring is limited. It is associated with improved perinatal outcome and could lower cesarean delivery rates in low-resource countries.

Topics: Amnion; Amniotic Fluid; Apgar Score; Cesarean Section; Developing Countries; Female; Fetal Distress; Hospitals, Teaching; Humans; India; Infant Mortality; Infant, Newborn; Infusions, Parenteral; Injections; Meconium; Meconium Aspiration Syndrome; Obstetric Labor Complications; Pregnancy; Prospective Studies; Rural Population; Sodium Chloride; Treatment Outcome

To investigate the effect of infusion of sodium bicarbonate in amniotic cavity and exchange of amniotic fluid for fetus with distress and acidosis.. The patients included 40 cases of oligohydramnios with mild and serious abnormality of fetal heart rate and amniotic fluid contamination of degree II or more during the labor. The 40 cases had exchange of amniotic fluid with infusion under continuous monitoring. Twenty of them had infusion with 5% sodium bicarbonate into amniotic cavity; the other 20 cases received 5% sodium bicarbonate intravenous in fusion. After the labor all the patients had test of arterial blood gas in umbilical cord and the fetuses were evaluated with Apgar score.. (1) the effective rate was 88% in the group of infusion into amniotic cavity and 85% in the group of exchange of amniotic fluid. (2) The arterial blood pH, PO(2), HCO(3)(-), ABE, SBE in the group of amniotic cavity infusion with 5% sodium bicarbonate were all higher than group of IV infusion, however PCO(2) was significantly lower than the group of IV (P < 0.05).. Infusion into amniotic cavity and exchange of amniotic fluid is effective therapy for fetal distress due to oligohydramnios and can prevent meconium aspiration syndrome; infusion of antacids medicine (5% sodium bicarbonate) into amniotic cavity is effective and safe therapy for fetus with acidosis.

Topics: Acidosis; Adult; Amnion; Amniotic Fluid; Apgar Score; Dose-Response Relationship, Drug; Female; Fetal Distress; Fluid Therapy; Heart Rate, Fetal; Humans; Infant, Newborn; Infusions, Intravenous; Infusions, Parenteral; Labor, Obstetric; Meconium; Meconium Aspiration Syndrome; Oligohydramnios; Pregnancy; Sodium Bicarbonate

There are conflicting reports regarding the results of amnioinfusion in the management of meconium passage in utero. This study was done to evaluate transcervical amnioinfusion for meconium stained amniotic fluid during labour.. 196 women at term in early labour with meconium were randomized to receive either transcervical intrapartum amnioinfusion with saline (96) or routine obstetrical care (100). Transcervical amnioinfusion of one liter saline infused over 30-45 minutes. End points were relief of decelerations, incidence of vaginal delivery, presence of meconium below the neonatal cords, and X-ray evidence of meconium aspiration.. Amnioinfusion resulted in relief of decelerations in 75% of cases as compared to 7% in the control group. Eighty-eight percent of patients delivered vaginally as compared to 58% in the control group (p< 0.001). Neonatal outcome was significantly better in the infusion group. The incidence of meconium below the vocal cords was reduced from 48% to 17% (p< 0.004) using amnioinfusion with positive X-rays for meconium aspiration in only 12.5% versus 26% (p < 0.5).. We concluded that transcervical intrapartum amnioinfusion is a safe, simple and inexpensive technique that reduces operative intervention and improves neonatal outcome, and is of tremendous relevance in developing countries.

Topics: Amniotic Fluid; Female; Humans; Infant, Newborn; Infusions, Parenteral; Labor, Obstetric; Meconium; Meconium Aspiration Syndrome; Pregnancy; Pregnancy Outcome; Sodium Chloride

To assess the effect of amnioinfusion during labour with meconium stained amniotic fluid on caesarean section rate and perinatal outcome.. Prospective randomised controlled study.. A tertiary care teaching hospital in India.. Women in labour at term with meconium stained amniotic fluid.. Two hundred women in labour with > or = 37 weeks gestation, single cephalic presentation with moderate or thick meconium were randomised to control and amnioinfusion groups at a 1:1 ratio. Amnioinfusion was performed using 500 mL of normal saline over a period of 30 minutes in a study group. The control group received routine care. Both groups had intermittent auscultation of fetal heart rate during labour.. The primary outcome measure was caesarean section rate. Secondary outcome measures were meconium aspiration syndrome, 1 minute and 5 minute apgar < 7, hypoxic ischaemic encephalopathy, neonatal intensive care unit admission, meconium at the level of vocal cords.. The caesarean section rate in the amnioinfusion group was less than the control group (RR 0.47; 95% CI 0.24-0.93). Amnioinfusion was associated with a significant decrease in the incidence of meconium at the vocal cords (P = 0.001); improvement in 1 minute apgar scores (P < 0.05), respiratory distress (P = 0.002) and fewer admissions to nursery compared with the controls. This sample size was inadequate to study the impact on meconium aspiration syndrome.. Amnioinfusion in an under resourced labour ward decreases caesarean section rates and fetal morbidity.

Topics: Adult; Amnion; Cesarean Section; Extraction, Obstetrical; Female; Fetal Distress; Fever; Humans; Infant, Newborn; Meconium; Meconium Aspiration Syndrome; Pregnancy; Pregnancy Outcome; Prospective Studies; Puerperal Disorders; Risk Factors

To determine risk factors for meconium aspiration syndrome (MAS).. A cohort study was conducted of 70 consecutive singleton pregnancies complicated with thick meconium-stained amniotic fluid delivered at > or = 37 weeks' gestation. Cases were randomized either for elective abdominal delivery or spontaneous vaginal delivery after 20 min of external fetal heart rate (FHR) monitoring. Risk estimation analysis for MAS was performed calculating relative risks (RR) and odds ratios (OR).. The presence of meconium below the vocal cords (RR=7.3, 95% CI=2.6-20.3), non-reassuring FHR tracings (RR=3.0, 95% CI=1.2-7.5), Apgar score < or = 6 at 5 min (RR=3.8, 95% CI=1.7-8.4) and an umbilical cord plasma erythropoietin (UCPer) level > 50 mlU/ml (RR=5.0, 95% CI=2.1-12.0) were found to be significant risk factors for MAS. The presence of meconium below the vocal cords (OR=33.4, 95% CI=3.6-303.7) and non-reassuring FHR tracings (OR=12.2, 95% CI=1.3-111.7) remained as significant risk factors at the end of the multivariate analysis.. Non-reassuring FHR tracings and the presence of meconium below vocal cords are associated with an increased risk for MAS in infants born through thick meconium.

Topics: Adult; Amniocentesis; Chi-Square Distribution; Cohort Studies; Confidence Intervals; Delivery, Obstetric; Female; Humans; Incidence; Infant, Newborn; Logistic Models; Meconium; Meconium Aspiration Syndrome; Multivariate Analysis; Obstetric Labor Complications; Pregnancy; Prognosis; Risk Factors; Syndrome

To investigate the effect of amnioinfusion in women with meconium-stained amniotic fluid on the rate of cesarian sections and on neonatal morbidity.. A randomized controlled trial. A total of 206 women with meconium-stained amniotic fluid were assigned to receive amnioinfusion via two-way catheter or no amnioinfusion (control group). The catheter was inserted and other treatment was the same in both groups.. Amnioinfusion decreased the rate of cesarian sections for fetal distress (RR 0.23, 95% CI 0.07-0.79) and increased mean pH at birth (7.24+/-0.1 versus 7.21+/-0.1, P<0.05). It also decreased the frequency of variable fetal heart rate decelerations (RR 0.74, 95% CI 0.59-0.92), and of meconium below the vocal cords in neonates (RR 0.37, 95% CI 0.19-0.69).. Amnioinfusion improves the neonatal outcome and reduces the frequency of cesarian sections.

Topics: Adult; Amniotic Fluid; Cesarean Section; Delivery, Obstetric; Female; Fetal Distress; Heart Rate, Fetal; Humans; Infant, Newborn; Infusions, Parenteral; Labor, Obstetric; Meconium; Meconium Aspiration Syndrome; Obstetric Labor Complications; Pregnancy; Pregnancy Outcome

Disagreement exists concerning the appropriate delivery room management of the airway of vigorous meconium-stained infants. Some suggest a universal approach to intubation and suctioning of the airway in all such neonates, whereas others advocate a selective approach. We performed this investigation: 1) to assess whether intubation and suctioning of apparently vigorous, meconium-stained neonates would reduce the incidence of meconium aspiration syndrome (MAS); and 2) to determine the frequency of complications from delivery room intubation and suctioning of such infants.. Inclusion criteria included: 1) gestational age >/=37 weeks; 2) birth through meconium-stained amniotic fluid of any consistency; and 3) apparent vigor immediately after birth. Subjects were randomized to be intubated and suctioned (INT) or to expectant management (EXP). Primary outcome measures included: 1) the incidence of respiratory distress, including MAS, and 2) the incidence of complications from intubation.. A total of 2094 neonates were enrolled from 12 participating centers (1051 INT and 1043 EXP). Meconium-stained amniotic fluid consistency was similar in both groups. Of the 149 (7.1%) infants that subsequently demonstrated respiratory distress, 62 (3.0%) had MAS and 87 (4.2%) had findings attributed to other disorders. There were no significant differences between groups in the occurrence of MAS (INT = 3.2%; EXP = 2.7%) or in the development of other respiratory disorders (INT = 3.8%; EXP = 4.5%). Of 1098 successfully intubated infants, 42 (3.8%) had a total of 51 complications of the procedure. In all cases, the complications were mild and transient in nature.. Compared with expectant management, intubation and suctioning of the apparently vigorous meconium-stained infant does not result in a decreased incidence of MAS or other respiratory disorders. Complications of intubation are infrequent and short-lived.

Topics: Adult; Delivery Rooms; Female; Humans; Incidence; Infant, Newborn; Intubation, Intratracheal; Male; Meconium; Meconium Aspiration Syndrome; Pregnancy; Prospective Studies; Risk Factors; Suction

Meconium staining of the amniotic fluid in labor is a frequent problem that is associated with an increase in the risk of neonatal and maternal morbidity. Amnioinfusion is a simple technique that is designed to prevent neonatal and maternal morbidity associated with meconium. Preliminary studies indicate that amnioinfusion is a promising approach to the prevention of such complications of labor. However, further research is required. The primary objective of this multi-centre randomized controlled study is to determine if amnioinfusion for thick meconium stained amniotic fluid results in a reduction in perinatal death or moderate to severe meconium aspiration syndrome. We will also assess the effects of amnioinfusion on other indicators of neonatal morbidity and on cesarean section. The study includes an evaluation of womens views on their childbirth experience and an economic evaluation of a policy of amnioinfusion The study will be achieved with the collaboration of approximately 50 obstetrical centres from across Canada, US, Europe, South America and South Africa. This multicentre trial will provide urgently needed information on the efficacy and effectiveness of amniofusion for the indication of meconium stained amniotic fluid.

Topics: Amniotic Fluid; Humans; Infant, Newborn; Infant, Newborn, Diseases; Meconium; Meconium Aspiration Syndrome; Multicenter Studies as Topic; Patient Selection; Randomized Controlled Trials as Topic

To evaluate transcervical amnioinfusion for meconium stained amniotic fluid during labout.. Multicentre randomised controlled trial.. Four urban academic hospitals in South Africa. Obstetric surveillance included the use of electronic fetal heart rate monitoring in most cases.. Women in labour at term with moderate or thick meconium staining of the amniotic fluid.. Transcervical amnioinfusion of 800 mL saline at 15 mL per minute, followed by a maintenance infusion at 3 mL per minute. The control group received routine care. Blinding of the intervention was not possible.. Caesarean section, meconium aspiration syndrome and perinatal mortality.. Caesarean section rates were similar (amnioinfusion group 70/167 vs control group 68/159; RR 0.98, 95% CI 0.76-1.26). The incidence of meconium aspiration syndrome was lower than expected on the basis of previous studies (4/162 vs 6/163; RR 0.67, 95% CI 0.19-2.33). There were no perinatal deaths. There were no significant differences between any of the subsidiary outcomes.. This study concurred with three previous trials which found no effect of amnioinfusion for meconium-stained amniotic fluid on caesarean section rate, though the pooled data from all identified trials to date show a significant reduction. The findings with respect to meconium aspiration syndrome were inconclusive in this study alone because of the small number of babies affected, but the point estimate of the relative risk was consistent with the finding of a significant reduction in previous studies and with the Zimbabwe arm (CRAMP 2) of this study. Pooled data clearly support the use of amnioinfusion for meconium stained amniotic fluid to reduce the incidence of meconium aspiration syndrome.. Numerous clinical trials have indicated that amnioinfusion for potential or suspected umbilical cord compression reduces the frequency of fetal heart rate decelerations and cesarean section. The present study, conducted at four urban teaching hospitals in South Africa, further evaluated the benefits of transcervical amnioinfusion for meconium-stained amniotic fluid during labor on perinatal outcome. In the intervention group (n = 176), 800 ml of saline was amnioinfused at 15 ml/minute, followed by a maintenance dose of 3 ml/minute for the duration of labor. The control group (n = 176) received routine obstetric care. There were 70 cesarean sections in the amnioinfusion group and 68 in the control group (relative risk (RR), 0.98; 95% confidence interval (CI), 0.76-1.26). The prevalence of meconium aspiration syndrome was unexpectedly low: 4 cases in the intervention group and 6 cases in the control group (RR, 0.67; 95% CI, 0.19-2.33). There were no perinatal deaths in either group. Subsidiary outcomes (e.g., Apgar score, assisted delivery, cord pH, neonatal ventilation) did not differ between groups. These findings provide preliminary support for use of amnioinfusion in women whose fetuses are considered at risk of meconium aspiration syndrome. A similar study conducted in Zimbabwe demonstrated larger effects of amnioinfusion on reductions in cesarean section, meconium aspiration syndrome, and perinatal mortality.

Topics: Amnion; Cesarean Section; Female; Humans; Infant, Newborn; Meconium; Meconium Aspiration Syndrome; Obstetric Labor Complications; Pregnancy; Sodium Chloride; South Africa; Urban Health

To evaluate transcervical amnioinfusion for meconium stained amniotic fluid during labour.. Multicentre randomised controlled trial.. A large urban academic hospital. Electronic fetal heart rate monitoring was not used.. Women in labour at term with moderate or thick meconium staining of the amniotic fluid.. Transcervical amnioinfusion of 500 mL saline over 30 minutes, then 500 mL at 30 drops per minute. The control group received routine care. Blinding of the intervention was not possible.. Caesarean section, meconium aspiration syndrome and perinatal mortality.. There was no difference in risk for caesarean section in the two groups (amnioinfusion 9.5% vs control 12.3%; RR 0.84, 95% CI 0.53-1.32). Meconium aspiration syndrome was significantly less frequent in the amnioinfusion group (3.1% vs 12.8%; RR 0.24, 95% CI 0.12-0.48), and there was a trend towards fewer perinatal deaths (1.2% vs 3.6%; RR 0.34, 95% CI 0.11-1.06).. Amnioinfusion is technically feasible in a developing country situation with limited intrapartum facilities. In this study amnioinfusion for meconium stained amniotic fluid was associated with striking improvements in perinatal outcome.. The presence of meconium in the amniotic fluid is associated with increased perinatal morbidity and mortality. Saline amnioinfusion during labor has been shown, in several clinical trials, to reduce the incidence of cesarean section and meconium aspiration syndrome. A randomized controlled trial conducted at Harare Maternity Hospital in Zimbabwe sought to confirm the benefits of amnioinfusion for meconium-stained amniotic fluid during labor for perinatal outcome. In the intervention group (n = 325), 500 ml of saline was transcervically amnioinfused over a 30-minute period, followed by 500 ml at 30 drops per minute for the duration of labor. The control group (n = 336) received routine obstetric care. The cesarean section rate was 9.5% in the intervention group and 12.3% in the control group (relative risk (RR), 0.84; 95% confidence interval (CI), 0.53-1.32). Meconium aspiration syndrome was significantly less frequent in the amnioinfusion group (3.1%) than the control group (12.8%) (RR, 0.24; 95% CI, 0.12-0.48). The perinatal death rate was 1.2% in the amnioinfusion group and 3.6% among controls (RR, 0.34; 95% CI, 0.11-1.06). Also recorded in the amnioinfusion group were significant reductions in the following perinatal morbidity measures: 5-minute Apgar score below 7, neonatal intensive care admissions, neonatal ventilation, and hypoxic ischemic encephalopathy. The striking improvements in perinatal outcome recorded among women in the amnioinfusion group suggest the feasibility of more widespread use of this simple procedure in developing country settings without routine electronic fetal monitoring facilities.

Topics: Abnormalities, Multiple; Adult; Amnion; Cesarean Section; Female; Fetal Death; Hospitalization; Humans; Infant, Newborn; Intensive Care, Neonatal; Meconium; Meconium Aspiration Syndrome; Obstetric Labor Complications; Pregnancy; Pregnancy Outcome; Sodium Chloride; Urban Health; Zimbabwe

We hypothesized that prophylactic intrapartum amnioinfusion in pregnancies complicated by thick meconium will not decrease the incidence of fetal distress, cesarean section for fetal distress, or meconium below the cords.. Patients with thick meconium were randomized to amnioinfusion (n = 65) or control (n = 59). The amnioinfusion group received an 800 ml bolus of normal saline solution followed by a continuous infusion at 180 ml/hr. Continuous variables were compared by Student t test, and discrete variables were compared by chi 2 analysis and Fisher's exact test as appropriate.. The incidence of fetal distress (16 of 65 vs 8 of 59) and cesarean section for fetal distress (seven of 65 vs seven of 59) was not significantly different between the amnioinfusion and control groups, respectively. The rate of meconium below the cords (one of 65 vs eight of 59) was significantly lower in patients receiving amnioinfusion (relative risk 0.09, confidence interval 0.01 and 0.82, p = 0.02). Two cases of meconium aspiration syndrome occurred in control patients but in none receiving amnioinfusion (p = 0.22).. Prophylactic amnioinfusion in patients with thick meconium decreases the incidence of meconium below the cords and may subsequently have an impact on the incidence of meconium aspiration syndrome in larger series.

Topics: Adolescent; Adult; Amnion; Cesarean Section; Chi-Square Distribution; Female; Fetal Distress; Humans; Incidence; Infant, Newborn; Infusions, Parenteral; Meconium; Meconium Aspiration Syndrome; Pregnancy; Pregnancy Complications; Pregnancy Outcome; Sodium Chloride

Previous studies have demonstrated reduced perinatal morbidity in patients receiving amnioinfusion for meconium-stained amniotic fluid compared with control patients receiving no amnioinfusion. Because amnioinfusion for variable fetal heart rate decelerations has become accepted care, we sought to determine the benefit of prophylactic amnioinfusion for meconium compared with standard care, incorporating therapeutic amnioinfusion for variable decelerations.. Ninety-three term patients with moderate to heavy meconium and no variable fetal heart rate decelerations were randomized to immediate prophylactic amnioinfusion (600 ml saline solution bolus followed by 3 ml/min) or to standard care (including therapeutic amnioinfusion for variable decelerations developing later). All babies had DeLee suctioning on delivery of the head. Laryngeal cords were visualized and tracheal suctioning performed when meconium was seen below the cords. Statistical comparisons were performed using Student t test, Fisher's exact test, or chi 2 analysis.. There were no significant differences in the incidence of operative delivery, fetal distress, or meconium below the cords or in newborn Apgar scores and umbilical artery gas values between the amnioinfusion (n = 43) and control (n = 50) patients. There were four cases of meconium aspiration, three in the amnioinfusion group, one in the standard care group. The rate of endometritis-chorioamnionitis was higher (p = 0.3) in the amnioinfusion (16%) than in the control group (8%), although time from ruptured membranes to delivery (8.5 hours vs 7.3 hours) and duration of intrauterine monitoring (6.1 hours vs 5.3 hours) were not different.. Although amnioinfusion does dilute amniotic meconium, prophylactic amnioinfusion for meconium in the absence of variable decelerations remains controversial. Prophylactic amnioinfusion in term pregnancies did not improve perinatal outcome and increased the risk for chorioamnionitis-endometritis. Together with recent reports, the current data suggest that the benefit of amnioinfusion for meconium-stained amniotic fluid is a result of the alleviation of variable fetal heart rate decelerations rather than meconium dilution.

Topics: Adult; Amnion; Amniotic Fluid; Chi-Square Distribution; Chorioamnionitis; Endometritis; Female; Heart Rate, Fetal; Humans; Infant, Newborn; Infusions, Parenteral; Meconium; Meconium Aspiration Syndrome; Pregnancy; Pregnancy Outcome; Prospective Studies; Sodium Chloride

Our purpose was to evaluate the efficacy of prophylactic amnioinfusion in decreasing neonatal morbidity associated with labor complicated by particulate meconium-stained amniotic fluid and to assess potential complications of this procedure.. One hundred five laboring pregnant women with particulate (moderate or thick) meconium by subjective clinical analysis were randomly assigned to receive amnioinfusion or to receive standard obstetric care without amnioinfusion. Patients with any antepartum complications, other than the presence of meconium, were excluded from the study. Statistical analyses consisted of the two-tailed and paired Student t tests, Pearson chi 2 test, and Wilcoxon nonparametric test. Significance was set at p < 0.05.. The study included 47 patients in the study group and 58 patients in the control group. A significantly greater proportion of study patients demonstrated decreased meconium concentration between rupture of membranes and delivery (46 of 46 vs 15 of 58, p < 0.001). The relative dilution of meconium consistency by objective analysis was significantly different between the study group and the control group (77.1% decrease vs 9.3% increase, p < 0.001). The proportion of neonates with meconium below the vocal cords was reduced in the study group (two of 47 vs 36 of 58, p < 0.001). Umbilical artery pH was increased in the study group neonates (7.29 +/- 0.01 vs 7.25 +/- 0.009, p < 0.05). The rate of neonatal acidemia was reduced in the study group (4 of 45 vs 12 of 50, p < 0.05). The rate of meconium aspiration syndrome was reduced in the study group (1 of 47 vs 8 of 58, p < 0.05). Maternal and neonatal morbidity rates were similar.. Prophylactic amnioinfusion should be considered a possible addition to the intrapartum management of patients with particulate meconium-stained amniotic fluid.

Topics: Acidosis; Adult; Amnion; Amniotic Fluid; Female; Humans; Hydrogen-Ion Concentration; Infant, Newborn; Infusions, Parenteral; Meconium; Meconium Aspiration Syndrome; Obstetric Labor Complications; Pregnancy; Prospective Studies; Umbilical Arteries

To determine prospectively the incidence of several pulmonary diagnoses among infants born through clear or meconium-stained amniotic fluid (AF) managed by a selective approach to tracheal intubation.. All live births greater than 36 weeks' gestation occurring between January 1990 and December 1992 were included. Diagnostic criteria for several respiratory disorders were determined prospectively and monitored. Infants with light meconium and vigorous infants with moderate to thick meconium were selectively not suctioned. A control group of infants with clear AF matched for gestational age and year of birth was randomly selected for comparison. The incidence and severity of respiratory disease were compared between the groups.. Of 4938 live births, 799 (16%) had meconium-stained AF (light, 334; moderate to thick, 465). Compared to 211 infants with moderate to thick meconium selectively not suctioned, 196 suctioned infants had significantly greater rates of abnormal fetal heart rate (FHR) patterns, fetal acidosis, low Apgar scores at 5 minutes, need for resuscitation, and neonatal intensive care unit admission. Meconium aspiration syndrome was significantly more common in suctioned infants as compared to those selectively not suctioned, those with light meconium, and those with clear fluid (11 versus 3 versus 0 versus 0%; P < .01). The need for ventilator or oxygen support was similar between infants with clear fluid, lightly stained fluid, and moderate to thick fluid who were selectively not suctioned, but was significantly greater among suctioned infants (P < .01).. We conclude that a selective approach to tracheal intubation and suction of infants with meconium-stained AF was not associated with increased pulmonary morbidity or mortality. Postnatal management of neonates at greatest risk of meconium aspiration syndrome does not necessarily prevent adverse pulmonary outcome.

Topics: Amniotic Fluid; Humans; Incidence; Infant, Newborn; Intubation, Intratracheal; Lung Diseases; Meconium; Meconium Aspiration Syndrome; Prospective Studies; Risk; Suction

The null hypothesis is that the use of intrapartum amnioinfusion in labors complicated by the presence of thick meconium and oligohydramnios will not decrease the incidence of fetal distress, cesarean delivery, meconium aspiration, or meconium aspiration syndrome.. One hundred seventy term and postterm patients with thick meconium and oligohydramnios were randomly chosen to receive amnioinfusion or standard obstetric care without amnioinfusion. The frequency of fetal distress, cesarean section, meconium aspiration, and meconium aspiration syndrome were subject to chi 2 analysis, Student's t test, or Fisher's exact test.. The rate of fetal distress was significantly reduced in the amnioinfusion group compared with controls (three of 85 vs 19 of 85, relative risk 0.15, 95% confidence interval 0.06 to 0.42). The rate of cesarean section for fetal distress was significantly reduced in the amnioinfusion group (two of 85 vs 17 of 85, relative risk 0.118, confidence interval 0.03 to 0.49). The rates of meconium aspiration (four of 85 vs 33 of 85, relative risk 0.12, confidence interval 0.0449 to 0.327) and meconium aspiration syndrome (0 of 85 vs five of 85, relative risk 0.09, confidence interval 0.009 to 0.872) were significantly reduced by amnioinfusion.. Amnioinfusion improves the outcome in pregnancies complicated by thick meconium and oligohydramnios.

Topics: Amnion; Cesarean Section; Female; Fetal Distress; Humans; Hydrogen-Ion Concentration; Infant, Newborn; Meconium; Meconium Aspiration Syndrome; Obstetric Labor Complications; Oligohydramnios; Pregnancy; Prospective Studies; Sodium Chloride; Solutions; Syndrome; Umbilical Arteries

The presence of meconium-stained amniotic-fluid (MSAF) during labor in cephalic presentation is a potentially ominous sign of fetal distress and, a direct cause of meconium aspiration syndrome (MAS). The authors designed a new method of intrapartum amnioinfusion for replacement (IAR) of the MSAF with normal saline solution. A total of 177 parturients with MSAF were studied from July 1986 to January 1987. Seventy-three cases receiving IAR treatment were analysed and 104 cases treated routinely served as controls. The newborn infants receiving IAR treatment had a significantly lower incidence of neonatal asphyxia (P less than 0.001) and MAS (P less than 0.05). No neonatal death occurred in the treated group; whereas, three infants died in the controls. There was no significant difference in puerperal morbidity between these two groups. The results of this study suggest that IAR might be a hopeful and effective treatment for parturients with MSAF in reducing the incidence of MAS.

Topics: Amnion; Amniotic Fluid; Female; Humans; Infant, Newborn; Injections; Meconium; Meconium Aspiration Syndrome; Pregnancy; Sodium Chloride; Suction

Intrapartum suctioning of the newborn's pharynx with a De Lee catheter (DL) has reduced the incidence of meconium aspiration syndrome (MAS) in neonates born with meconium staining of the amniotic fluid. However, the bulb syringe (BLB) is used more often for this purpose because of greater technical convenience. In a prospective study, 60 offspring of such deliveries received intrapartum pharyngeal suctioning either by BLB (29 cases) or by DL (31 cases), according to random selection. The presence and amount of meconium in the trachea, incidence and severity of MAS, and mortality from the disease were similar between the two groups. This study suggests that the BLB is as effective as the DL for intrapartum removal of nasopharyngeal meconium in deliveries with meconium staining of the amniotic fluid. Since the BLB is easier to use, less expensive and probably safer, our results suggest that it may be the preferable method.

Topics: Amniotic Fluid; Catheterization; Delivery, Obstetric; Female; Humans; Infant, Newborn; Male; Meconium; Meconium Aspiration Syndrome; Nasopharynx; Pregnancy; Prospective Studies; Suction; Syringes; Trachea

The pathogenesis of neonatal meconium aspiration syndrome (MAS) involves meconium-induced lung inflammation and surfactant inactivation. Bronchoalveolar lavage (BAL) with diluted surfactant facilitates the removal of meconium. CHF5633, one of the most promising synthetic surfactants, is effective in neonatal respiratory distress syndrome. Here we investigated its efficacy via BAL in an experimental MAS model.. Experimental MAS was induced at birth in near-term newborn rabbits by intratracheal instillation of reconstituted human meconium. First, undiluted CHF5633 was compared with a porcine-derived surfactant (Poractant alfa) via intratracheal bolus (200 mg/kg). Second, the efficacy of BAL with diluted CHF5633 (5 mg/mL, 20 ml/kg) alone, or followed by undiluted boluses (100 or 300 mg/kg), was investigated.. Meconium instillation caused severe lung injury, reduced endogenous surfactant pool, and poor survival. CHF5633 had similar benefits in improving survival and alleviating lung injury as Poractant alfa. CHF5633 BAL plus higher boluses exerted better effects than BAL or bolus alone in lung injury alleviation by reversing phospholipid pools and mitigating proinflammatory cytokine mRNA expression, without fluid retention and function deterioration.. CHF5633 improved survival and alleviated meconium-induced lung injury, the same as Poractant alfa. CHF5633 BAL plus boluses was the optimal modality, which warrants further clinical investigation.. To explore the efficacy of a synthetic surfactant, CHF5633, in neonatal lung protection comparing with Poractant alfa in a near-term newborn rabbit model with meconium-induced lung injury. Similar effects on improving survival and alleviating lung injury were found between CHF5633 and Poractant alfa. Optimal therapeutic effects were identified from the diluted CHF5633 bronchoalveolar lavage followed by its undiluted bolus instillation compared to the lavage or bolus alone regimens. Animals with CHF5633 lavage plus bolus regimen exerted neither substantial lung fluid retention nor lung mechanics deterioration but a trend of higher pulmonary surfactant-associated phospholipid pools.

Topics: Animals; Animals, Newborn; Female; Humans; Infant, Newborn; Lung Injury; Meconium; Meconium Aspiration Syndrome; Phospholipids; Pneumonia; Pulmonary Surfactants; Rabbits; Surface-Active Agents; Swine; Therapeutic Irrigation

Topics: Amniotic Fluid; Female; Humans; Infant; Infant, Newborn; Infant, Newborn, Diseases; Meconium; Meconium Aspiration Syndrome

The Neonatal Life Support 2020 guidelines emphasize that meconium-stained amniotic fluid (MSAF) remains a significant risk factor for a newborn to receive advanced resuscitation, especially if additional risk factors are present at the time of birth. However, these additional perinatal risk factors are not clearly identified. The purpose of this study was to evaluate the importance of additional independent ante- and intrapartum risk factors in the era of no routine endotracheal suctioning that determine the need for resuscitation in newborns born through MSAF.. This retrospective cohort study included deliveries ≥ 35 weeks' gestation associated with MSAF that occurred between January 1, 2017 and December 31, 2019. The newborns needing resuscitation (any intervention beyond the initial steps) were compared to those not needing resuscitation. Among newborns needing resuscitation, those needing advanced resuscitation (continuous positive airway pressure/ positive pressure ventilation or beyond) were compared to those not needing advanced resuscitation.. Logistic regression analysis revealed that among various perinatal factors, primigravida, thick meconium, fetal distress, chorioamnionitis, rupture of membranes ≥ 18 hours, post-term (gestational age ≥ 42 weeks), cesarean section or shoulder dystocia independently significantly increased the odds of a meconium-stained newborn needing resuscitation. Among these factors, fetal distress, chorioamnionitis or cesarean section independently further increased the odds of needing advanced resuscitation.. Risk stratification of perinatal factors associated with the need for newborn resuscitation and advanced resuscitation in the deliveries associated with MSAF may help neonatal teams and resources to be appropriately prioritized and optimally utilized.

Topics: Amniotic Fluid; Cesarean Section; Chorioamnionitis; Female; Fetal Distress; Humans; Infant; Infant, Newborn; Meconium; Meconium Aspiration Syndrome; Pregnancy; Pregnancy Complications; Retrospective Studies; Risk Factors

A shift in the Neonatal Resuscitation Program (NRP) guidelines occurred in 2015 from routine intubation and endotracheal suctioning of all meconium-stained non-vigorous infants towards less aggressive interventions based on response to initial resuscitation. This study aims to examine the impact of this change on outcomes of non-vigorous infants born through meconium-stained amniotic fluid at a level III academic NICU encompassing years before and after the change in guideline. This single-center retrospective study compared NICU therapies and clinical outcomes of 117 non-vigorous newborns pre-guideline implementation to 106 non-vigorous newborns post-guideline implementation. Nearly two thirds of infants in the pre-guideline cohort received endotracheal suctioning with recovery of meconium compared to less than a third of infants in the post-guideline cohort (p<0.01). Though a higher proportion of the pre-guideline cohort were admitted to the NICU for respiratory issues compared to the post-guideline cohort, the two groups did not differ significantly with regard to morbidity and therapies. Despite a marked reduction in rates of intubation and endotracheal suctioning, there is no difference in outcomes between pre-guideline implementation vs post-guideline implementation in non-vigorous meconium-stained infants, supporting the recent NRP guideline change and highlighting the benefit of expectant management.

Topics: Amniotic Fluid; Female; Humans; Infant, Newborn; Infant, Newborn, Diseases; Intubation, Intratracheal; Meconium; Meconium Aspiration Syndrome; Resuscitation; Retrospective Studies

The passage of meconium during labor increased the chance of undesirable birth outcomes. The adverse effects of meconium are worsening in resource-limited countries. In Ethiopia, there is an argument concerning meconium's negative effects and management on pregnant women and their babies. Therefore, this study was intended to assess the adverse maternal and perinatal outcomes of meconium in term labor in the South Gondar Zone, Ethiopia.. A prospective cohort study was conducted using 580 laboring mothers (145 exposed and 435 nonexposed groups). A two-stage sampling method was implemented to get study subjects. The data were collected using an interviewer-administered structured questionnaire and a medical chart review. SPSS version 25 was used for data analysis. Chi-squared and Fisher's exact tests were used to compare the two groups' differences. The strength of the association was measured using relative risk with a 95% CI.. There was more operative delivery (28.3% versus 5.3%), puerperal sepsis (79.54% versus 2.06%), nonreassuring fetal heart rate pattern (29.7% versus 2.1%), meconium aspiration syndrome (7.58% versus 0.68%), neonatal sepsis (9% versus 4.1%), perinatal asphyxia (13.8% versus 7.6%), admission to the neonatal intensive care unit (23.4% versus 3.2%), and early neonatal deaths (4.8% versus 1.4%) among meconium stained groups as compared to the clear amniotic fluid groups.. Meconium-stained amniotic fluid significantly increased adverse maternal and perinatal outcomes in Ethiopia. The risk of perinatal asphyxia, nonreassuring fetal heart rate pattern, neonatal sepsis, meconium aspiration syndrome, admission to the NICU, early neonatal death, operative delivery, and puerperal sepsis were significantly higher in meconium-exposed groups. Special attention should be given to meconium-exposed mothers during the intrapartum period and in postnatal follow-up.

Topics: Amniotic Fluid; Asphyxia; Asphyxia Neonatorum; Ethiopia; Female; Hospitals; Humans; Infant, Newborn; Infant, Newborn, Diseases; Meconium; Meconium Aspiration Syndrome; Neonatal Sepsis; Pregnancy; Pregnancy Complications; Prospective Studies

To identify risk factors associated with the occurrence of meconium aspiration syndrome (MAS) among neonates.. A retrospective case-control study in a university affiliated tertiary medical center, including all neonates born with meconium stained amniotic fluid (MSAF) between March 2011 and March 2020. Patients were categorized by the occurrence of MAS. Demographic, pregnancy and delivery characteristics were compared between the two groups. Risk factors for MAS were analyzed.. Of 90 579 singleton deliveries, a total of 11 856 with MSAF were included. Of these newborns, 78 (0.66%) were diagnosed with MAS Four factors were independently associated with MAS: delivery at <38 0/7 weeks (aOR [95% CI]: 3.48 (1.02-11.84), P = 0.046); higher body mass index (aOR [95% CI]: 1.09 (1.02-1.16), P = 0.003); lower amniotic fluid index (aOR [95% CI]: 0.99 (0.98-0.99), P = 0.032); higher white blood cell count (aOR [95% CI]: 1.11 (1.02-1.20), P = 0.009). The presence of one, two and three of the above-mentioned risk factors yielded a risk for MAS of 0.8%, 2.5% and 100%, respectively.. We identified independent risk factors for MAS and developed a risk score calculator. This tool may assist physicians in the management of deliveries complicated by MSAF.

Topics: Amniotic Fluid; Case-Control Studies; Female; Humans; Infant, Newborn; Meconium; Meconium Aspiration Syndrome; Pregnancy; Retrospective Studies; Risk Factors

To evaluate the short-term outcomes of non-vigorous infants born through meconium-stained amniotic fluid (MSAF) before and after implementation of no-tracheal suctioning guidelines.. Single-center retrospective study of ≥36-week gestation neonates with MSAF.. During routine-suction era (9/2013-12/2014), 280/2306 neonates (12%) were born through MSAF and 39 (14%) were non-vigorous. Thirty (77%) of non-vigorous infants underwent tracheal suctioning. In the no-suction era (1/2017-12/2018), 282/2918 neonates (9.7%) were born through MSAF and 30 (10.6%) were non-vigorous and one needed intubation. Admissions for meconium aspiration syndrome (15% vs 53%) and respiratory distress (18% vs 57%) were significantly higher among non-vigorous infants in the no-suction era.. In this single-center study, non-vigorous infants born through MSAF without routine-tracheal suctioning had a higher incidence of NICU admission for MAS and respiratory distress compared to the routine-suction era. Multicenter randomized trials evaluating tracheal suction in non-vigorous infants with MSAF are warranted.

Topics: Amniotic Fluid; Female; Humans; Infant; Infant, Newborn; Infant, Newborn, Diseases; Meconium; Meconium Aspiration Syndrome; Respiratory Distress Syndrome; Retrospective Studies; Suction

Topics: Cesarean Section; Female; Humans; Infant Mortality; Infant, Newborn; Meconium; Meconium Aspiration Syndrome; Pregnancy

Meconium aspiration syndrome (MAS) in neonates born through meconium-stained amniotic fluid (MSAF) causes significant morbidity and mortality. Early recognition of at-risk neonates could help optimize treatment. The aim was to determine predictive characteristics of cord blood pH, base deficit and lactate with subsequent MAS. Receiver operating characteristic (ROC) curves with area under curve (AUC) were estimated. Among 231 MSAF complicated pregnancies, 25 (10.8%) had MAS. Mean cord pH was significantly lower in neonates with MAS compared to those without MAS (7.15 ± 0.11 vs. 7.26 ± 0.07; p < 0.001). Median lactate between the two groups [5.6 (7.5, 3.7) vs. 2.7 (4.5, 2.0)] and base deficit [-10.6 (-13.2, -4.2) vs. -3.7 (-6.3, -2.6)] also differed significantly (p = 0.01). ROC curve area for cord lactate, pH, and base deficit were 0.81, 0.79, and 0.75, respectively. The predictive cutoff values for pH, lactate, and base deficit were 7.20, 3.55 mmol/L, and -5.3 mmol/L, respectively.

Topics: Amniotic Fluid; Female; Fetal Blood; Humans; Infant, Newborn; Infant, Newborn, Diseases; Lactic Acid; Meconium; Meconium Aspiration Syndrome; Pregnancy

To study the feasibility of tracheal intubation for meconium suction immediately after birth of nonvigorous neonates born through meconium-stained amniotic fluid (MSAF).. A retrospective cohort study was performed on nonvigorous neonates born through MSAF who were admitted to the Department of Neonatology, Zhecheng People's Hospital. The neonates without meconium suction who were admitted from July 1, 2017 to June 30, 2018 were enrolled as the control group. The neonates who underwent meconium suction from July 1, 2018 to June 30, 2019 were enrolled as the suction group. The two groups were compared in terms of the mortality rate and the incidence rates of neonatal meconium aspiration syndrome (MAS), persistent pulmonary hypertension of the newborn, pneumothorax, and pulmonary hemorrhage.. There were 80 neonates in the control group and 71 in the suction group. There were no significant differences between the two groups in the incidence rates of MAS (11% vs 7%), persistent pulmonary hypertension of the newborn (5% vs 4%), pneumothorax (3% vs 1%), and death (0% vs 1%). Compared with the control group, the suction group had a significantly lower proportion of neonates requiring oxygen inhalation (16% vs 33%,. Although tracheal intubation for meconium suction immediately after birth may shorten the duration of respiratory support for mild respiratory problems, it cannot reduce the incidence rate of MAS, mortality rate, or the incidence rate of serious complications in nonvigorous infants born through MSAF.

Topics: Amniotic Fluid; Humans; Infant; Infant, Newborn; Intubation, Intratracheal; Meconium; Meconium Aspiration Syndrome; Retrospective Studies; Suction

Delivery room management of infants delivered through meconium stained amniotic fluid has evolved over the past four decades. The burden of disease weighs more heavily in low- and middle-resource areas. Current information does not allow for precise prediction of infants that will require resuscitation at delivery versus those that need simple stabilization. Optimal care of newborns requires assessment of risk factors and obstetrical and pediatric team preparation to respond to the needs of the newborn.

Topics: Amniotic Fluid; Child; Female; Humans; Infant; Infant, Newborn; Infant, Newborn, Diseases; Meconium; Meconium Aspiration Syndrome; Suction

We aimed to evaluate the association between meconium-stained amniotic fluid during labor and offspring's childhood wheezing. This study analyzed the data of participants enrolled in the Japan Environment and Children's Study, a nationwide prospective birth cohort study, between 2011 and 2014. Data of women with singleton live births between 22 and 40 weeks' gestation were analyzed. Participants were categorized into two groups according to the presence or absence of meconium-stained amniotic fluid. The primary outcome measure was the offspring's childhood wheezing up to 3 years of age. A logistic regression model was used to calculate the adjusted odds ratio for childhood wheezing in children of women with meconium-stained amniotic fluid, considering those without meconium-stained amniotic fluid as a reference, taking into account the potential confounding factors affecting the incidence of wheezing. We analyzed data from 61,991 participants: 1796 (2.9%) participants had meconium-stained amniotic fluid during labor and 18,919 (30.5%) of the offspring had childhood wheezing. The adjusted odds ratios for the offspring's childhood wheezing were 0.89 (95% confidence interval, 0.79-0.99) in total participants, 0.87 (95% confidence interval, 0.78-0.97) in term births, and 2.00 (95% confidence interval, 0.98-4.09) in preterm births.. This study revealed a decreased incidence of childhood wheezing among the children of women with meconium-stained amniotic fluid in term births. By yet unknown mechanisms, meconium-stained amniotic fluid was associated with a decreased incidence of childhood wheezing in the offspring. Further studies are required to clarify the mechanism of one's own meconium in affecting their health condition.. • Meconium-stained amniotic fluid during labor is associated with several adverse perinatal outcomes, and meconium aspiration syndrome is associated with offspring's childhood asthma and wheezing. • Meconium-stained amniotic fluid during labor could be an independent protective factor for the offspring's dermatitis and skin rash.. • Whole cases with meconium-stained amniotic fluid during labor were associated with a decreased incidence of offspring's childhood wheezing up to 3 years of age. • This study may shed light on the effects of simple meconium-stained amniotic fluid on offspring's childhood health.

Topics: Amniotic Fluid; Child; Cohort Studies; Female; Humans; Infant, Newborn; Infant, Newborn, Diseases; Japan; Meconium; Meconium Aspiration Syndrome; Pregnancy; Pregnancy Complications; Prospective Studies; Protective Factors; Respiratory Sounds

The mortality and morbidity of meconium aspiration syndrome in neonates born with meconium-stained amniotic fluid in developing countries are still high. In Nepal, few studies have estimated the prevalence of meconium-stained amniotic fluid among newborns. The study aimed to find out the prevalence of neonates born through meconium-stained amniotic fluid among deliveries in a tertiary care centre.. This descriptive cross-sectional study was conducted among neonates born in a tertiary care centre from November 2021 to March 2022. Neonates born during the study period with meconium-stained amniotic fluid were studied. Ethical approval was obtained from the Institutional Review Committee. Convenience sampling method was used. With permission from the Department of the Neonatal Intensive Care Unit, the data were collected and entered in a Microsoft Excel sheet. Point estimate and 95% Confidence Interval were calculated.. Among 576 neonates, the prevalence of neonates born through meconium-stained amniotic fluid was 77 (13.37%) (10.59-16.15, 95% Confidence Interval).. The prevalence of neonates born through meconium-stained amniotic fluid was found to be similar to other studies done in similar settings.. meconium; neonate; Nepal.

Topics: Amniotic Fluid; Cross-Sectional Studies; Female; Humans; Infant, Newborn; Meconium; Meconium Aspiration Syndrome; Pregnancy Complications; Tertiary Care Centers

Although the precise aetiology of meconium-stained amniotic fluid is still unclear, risk factors include advanced gestational age at delivery, mode of delivery, the prolonged second stage of labour, and intrauterine infection. It has been associated with poor perinatal outcomes including low Apgar scores, increased incidence of neonatal intensive care admission, and a high rate of perinatal death. The objective of the study was to find out the prevalence of meconium-stained amniotic fluid in term deliveries in a tertiary care centre.. A descriptive cross-sectional study was done among term deliveries in the Department of Obstetrics and Gynaecology, in a tertiary care centre from inpatient records starting from 1 November 2019 to 1 November 2020 after obtaining ethical approval from the Institutional Review Committee (Reference number: PMG1911281316). Convenience sampling was done. Point estimate and 95% Confidence Interval were calculated.. Out of 1699 term deliveries, meconium-stained amniotic fluid was seen in 91 (5.35%) (4.28-6.42, 95% Confidence Interval). Among these 69 (75.82%) newborns were delivered through lower segment caesarean section and 61 (67%) newborns had Grade II meconium-stained amniotic fluid.. The prevalence of meconium-stained amniotic fluid was similar to the studies done in similar settings.. apgar score; caesarean section; gestational age; perinatal death; pregnancy.

Topics: Amniotic Fluid; Cesarean Section; Cross-Sectional Studies; Female; Humans; Infant, Newborn; Meconium; Meconium Aspiration Syndrome; Perinatal Death; Pregnancy; Pregnancy Complications; Tertiary Care Centers

To examine the risk of meconium aspiration syndrome (MAS) by the week of gestational age in pregnancies with meconium-stained amniotic fluid (MSAF).. This is a retrospective cohort study derived from term pregnancies at a single tertiary institution over an 18-year period. Outcomes analyzed included MAS, acidemia, and Apgar scores. Univariate analysis was performed using chi-square and multivariable logistic regression was used to adjust for potential confounders.. A total of 34,303 deliveries ≥37 weeks were included; 23.7% were complicated by MSAF. Of the total study cohort, 272 (0.7%) neonates were diagnosed with MAS; this represented 3% of all deliveries complicated by MSAF. In the presence of MSAF, the risk of MAS increased with gestational age, from 1.3% at 38 weeks to 4.8% at 42 weeks (. In women with MSAF, as gestational age increases, the risk of meconium aspiration syndrome also increases. Other factors with late-term and post-term pregnancy besides the presence of meconium may contribute to the evolution of MAS.

Topics: Amniotic Fluid; Female; Gestational Age; Humans; Infant, Newborn; Meconium; Meconium Aspiration Syndrome; Pregnancy; Retrospective Studies

To evaluate the impact of prolonged exposure to meconium-stained amniotic fluid (MSAF), in women with term pre-labor spontaneous rupture of membranes (PROM), on pregnancy outcome.. A retrospective cohort study of women who gave birth in a single university-affiliated tertiary medical center (2011-2019). Eligibility was limited to singleton pregnancies at term who presented with PROM. Women with MSAF were immediately induced and were compared to low-risk pregnant women with clear amniotic fluid (CAF) at admission who underwent induction of labor 24 h after rupture of membranes. All women were stratified into 4-time frame groups from rupture of membranes to delivery: T0: 0-7 h, T1: 8-13 h, T2: 14-18 h, and T3: > 18 h for the MSAF group. The time frames for the CAF were: T0 - 24-31 h, T1: 32-38 h, T2: 40-44 h, and T3: > 44 h. The maternal adverse composite outcome included any of the following: intrapartum fever (IPF), prolonged second stage (PSS), need for manual removal of suspected retained placenta, postpartum hemorrhage, and readmission within 45 days after delivery. The adverse composite neonatal outcome included one or more of the following: meconium aspiration syndrome, neonatal asphyxia, need for respiratory support, and intracranial hemorrhage.. Prolonged rupture of membranes in the presence of meconium does not affect maternal outcomes, however, prolonged exposure to meconium lead to an increased adverse neonatal outcome.

Topics: Amniotic Fluid; Female; Humans; Infant, Newborn; Infant, Newborn, Diseases; Meconium; Meconium Aspiration Syndrome; Placenta, Retained; Postpartum Hemorrhage; Pregnancy; Pregnancy Complications; Pregnancy Outcome; Premature Birth; Retrospective Studies; Rupture, Spontaneous

Meconium aspiration syndrome (MAS) is a disease closely related to inflammation and oxidative stress. Glycyrrhizic acid (GA) is a triterpenoid isolated from licorice with multiple bioprotective properties. In the present study, impacts of GA against MAS rats, as well as the potential mechanism, will be investigated. MAS model was established on newborn rats, followed by the treatment of 12.5, 25, and 50 mg/kg GA. The wet/dry weight ratio of lung tissues was calculated. The production of IL-6, IL-1β, TNF-α, malonaldehyde (MDA), superoxide dismutase (SOD), glutathione (GSH) was measured using ELISA assay. HE staining was used to evaluate the pathological state of lung tissues and TUNEL assay was used to detect the apoptotic state. The protein expression of Nrf2, Keap1, HO-1, Bcl-2, Bax, and cleaved-Caspase3 was measured by Western blotting assay. The elevated W/D ratio, release of inflammatory factors, lung injury score, and apoptotic index, as well as the activated oxidative stress and suppressed Keap1/Nrf2/HO-1 pathway, in MAS rats were significantly alleviated by GA. After introducing the inhibitor of Nrf2, ML385, the protective property of GA on the pathological state, apoptotic index, and oxidative stress in MAS rats was pronouncedly abolished. Taken together, glycyrrhizin alleviated GAH in rats by suppressing Keap1/Nrf2/HO-1 signaling mediated oxidative stress.

Topics: Acute Lung Injury; Animals; Animals, Newborn; Apoptosis; Glycyrrhizic Acid; Heme Oxygenase-1; Kelch-Like ECH-Associated Protein 1; Lung; Meconium; Meconium Aspiration Syndrome; NF-E2-Related Factor 2; Oxidative Stress; Protective Agents; Rats; Signal Transduction

Stillbirth is one of the most devastating adverse pregnancy outcome, but it is often associated with a missing post-mortem histological examination. We aimed at evaluating whether the staining of amniotic fluid reflects the fetal conditions surrounding the death and if it correlates with any histologic sign of fetal distress.. Terminal gasping (represented by the massive presence of intra-alveolar squamous cells), thymic and adrenal cortex modifications were evaluated as histologic signs of fetal distress in stillbirths, and stratified according to the degree of staining of the amniotic fluid.. The presence of meconium-stained amniotic fluid did not correlate with the presence of gasping and/or thymic and/or adrenal cortex changes. Clear amniotic fluid was not associated with the absence of histologic signs of distress.. The evaluation of the staining of the amniotic fluid fails to identify distressed fetuses. A histologic evaluation of fetal organs provides detailed information, irrespective of the presence/absence of meconium-stained amniotic fluid.

Topics: Amniotic Fluid; Female; Fetal Distress; Humans; Infant, Newborn; Meconium; Meconium Aspiration Syndrome; Pregnancy; Stillbirth

Topics: Amniotic Fluid; Humans; Infant, Newborn; Meconium; Meconium Aspiration Syndrome

We investigated the impact of policy change in delivery room resuscitation from routine endotracheal (ET) suctioning of non-vigorous neonates born through meconium-stained amniotic fluid (MSAF) to immediate non-invasive respiratory support.. Single-centre cohort study. Prospective group (October 2016-September 2017)-non-vigorous neonates born through MSAF managed according to the current (2015) guidance of commencing respiratory support without prior suctioning. Retrospective group (August 2015-July 2016)-non-vigorous neonates born through MSAF who underwent routine ET suctioning.. 1138 neonates born through MSAF were analysed. No differences in the incidence of meconium aspiration syndrome (MAS), requirement of mechanical ventilation, inhaled nitric oxide or surfactant therapy were found between groups. Less neonatal intensive care unit (NICU) admissions were necessary in the prospective cohort compared with the retrospective group (19.1% vs 55.6%, respectively; p<0.05).. The policy change towards not routinely suctioning non-vigorous neonates born through MSAF at birth was not associated with an increase in the local incidence of MAS and was associated with fewer NICU admissions.

Topics: Amniotic Fluid; Delivery, Obstetric; Female; Health Services Research; Humans; Incidence; Infant, Newborn; Intensive Care Units, Neonatal; Male; Meconium; Meconium Aspiration Syndrome; Noninvasive Ventilation; Outcome and Process Assessment, Health Care; Policy Making; Practice Guidelines as Topic; Resuscitation; Suction; United Kingdom

A meconium aspirator is a simple plastic adapter that allows for rapid suctioning of the trachea when attached to an endotracheal tube and a source of continuous negative pressure, as was historically done for suspected neonatal meconium aspiration. Adaptation of this technique for the emergent vacuum extraction of an obstructing tracheal foreign body in an adult has not been previously described.. We report the case of a 33-year-old woman with cardiorespiratory arrest after choking on food. Complete tracheal obstruction precluding oxygenation and ventilation due to aspirated chicken was diagnosed by emergency physicians and managed immediately with vacuum extraction using the technique described in this report. No additional airway interventions were necessary and the patient made a full neurologic recovery. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: Vacuum extraction using a meconium aspirator and modified endotracheal tube is a novel and potentially life-saving approach to the emergency management of airway obstruction after choking, especially if the foreign material is below the vocal cords and not amenable to manual extraction with a Magill forceps.

Topics: Adult; Emergency Service, Hospital; Female; Foreign Bodies; Humans; Infant, Newborn; Intubation, Intratracheal; Meconium; Meconium Aspiration Syndrome; Pregnancy; Trachea; Vacuum Extraction, Obstetrical

Intrauterine meconium passage in near term or term fetuses has been associated with feto-maternal stress factors and/or infection and is contributing to the increased rate of cesarean section. This study aimed to evaluate effect of mode of delivery on fetal outcome in pregnancy with meconium-stained liquor.. A cross sectional study was done in 2019 at a tertiary care center. Data was collected from women in labor, in whom meconium was seen after rupture of membrane. Out of these, 115 cases, who underwent cesarean delivery for meconium-stained liquor were enrolled in one group; while in another group 115 cases who delivered vaginally were enrolled and the fetal outcome was compared in between these two groups.. Out of 230 cases, most participants were from 21 to 25 years age group. Most of patients were primigravida accounting for 63%, and with mean gestational age of 39.4 weeks. Low Apgar score at one and 5 minutes, percentage of respiratory distress, perinatal asphyxia, need of bag and mask ventilation as mode of resuscitation were associated more with vaginal deliveries. Incidence of Neonatal Intensive Care Unit admission, meconium aspiration syndrome, and neonatal death were seen more in vaginal delivery in comparison to cesarean delivery.. There was no much difference in Apgar score at 5 minutes in either mode of delivery. Incidence of respiratory distress, perinatal asphyxia, Neonatal Intensive Care Unit admission, meconium aspiration syndrome and neonatal death were higher in vaginal delivery. Fetal morbidity and mortality were seen more in moderate to thick meconium-stained liquor.

Topics: Cesarean Section; Cross-Sectional Studies; Delivery, Obstetric; Female; Humans; Infant; Infant, Newborn; Meconium; Meconium Aspiration Syndrome; Nepal; Pregnancy; Pregnancy Outcome

In spite of significant advances in therapeutic, diagnostic and even medical modalities, meconium management continues to be a concern for management. It has been recently assumed that trace of lactate in both serum and urine can be a sign of the asphyxia in neonates. However, no study has been done on the prognostic value of increasing lactate concentration in umbilical cord blood for predicting the outcomes of meconium aspiration syndrome (MAS), which was our aim in this study.. Thin cross-sectional study was performed on 150 neonates suffering meconium aspiration syndrome who were admitted to Akbar Abadi hospital in Tehran between 2016 and 2018. Samples of umbilical cord blood were extracted from neonates and sent to the reference laboratory to measure lactate level as well as arterial blood gas analysis. The neonatal characteristics as well as postdelivery complications were also collected by reviewing the hospital recorded files.. Thick meconium stained amniotic fluid (TKMSF) was found in 40.0% and thin meconium stained amniotic fluid (TNMSF) in 60.0%. The mean level of lactate was significantly higher in those neonates with morbidities including pulmonary hemorrhage, persistent pulmonary hypertension of the neonate (PPHN), intraventricular hemorrhage (IVH), and respiratory failure requiring ventilation support. According to the ROC curve analysis, increasing lactate in umbilical cord blood could predict occurrence of pulmonary hemorrhage (AUC = 0.885), PPHN (AUC = 0.832), IVH (AUC = 0.898), and requiring ventilation (AUC = 0.833). Comparing the two groups with TKMSF and TNMSF showed higher gestational age, lower Apgar score, lower BE, higher PCO. The increase in lactate in the umbilical cord blood (>4.1 mmol/L with high sensitivity and specificity) can distinguish between thick meconium and thin meconium forms in amniotic acid and thus can determine the severity of MAS. Also, increasing serum lactate levels is an accurate indicator for predicting complications such as pulmonary hemorrhage, PPHN, IVH, and need for ventilation in newborns with this syndrome. This diagnostic accuracy is even beyond the usual markers for arterial gas analysis, such as PH, PCO

Topics: Amniotic Fluid; Cross-Sectional Studies; Female; Fetal Blood; Humans; Infant, Newborn; Iran; Lactic Acid; Meconium; Meconium Aspiration Syndrome; Prognosis

Topics: Amniotic Fluid; Delivery Rooms; Humans; Infant, Newborn; Infant, Newborn, Diseases; Meconium; Meconium Aspiration Syndrome; Pregnancy

Despite its prevalence and potential maternal and neonatal implications, the literature on the thickness levels of meconium stained amniotic fluid (MSAF) and its impact on neonatal outcomes is relatively outdated and relies on relatively small sample sizes.. To study if different thickness levels of MSAF correlate with adverse neonatal outcome.. A retrospective cohort study.. The medical records and neonatal charts of all women with a singleton pregnancy, who underwent a trial of labor, at 37 + 0/7 weeks or beyond, between 10/2008 and 7/2018 were reviewed.. The cohort was divided according to the level of meconium reported during labor into four groups: Clear (C group), Light meconium (LM group), Intermediate meconium (IM group), and Heavy meconium (HM group). Composite neonatal outcome included at least one of the following: umbilical artery pH ≤ 7.1, sepsis, need for blood transfusion, need for phototherapy, respiratory distress syndrome, meconium aspiration syndrome, need for mechanical ventilation support, necrotizing enterocolitis, intraventricular hemorrhage, hypoxic ischemic encephalopathy, periventricular leukomalacia, seizures, hypoglycemia, hypothermia, and death. Continuous parameters were compared with Anova's test or Kruskal Wallis, and categorical variables by chi-square test or Fisher exact test, as appropriate. Multivariant logistic regression was performed in order to eliminate possible cofounders.. Overall, 24,445 deliveries were reviewed (C-20,185, LM-1074, IM-2736, HM-450). Composite adverse neonatal outcome was more common with increasing thickness of MSAF. On multivariable analysis, IM and HM were independently associated with composite adverse neonatal outcome.. The degree of meconium thickness independently correlates with composite adverse neonatal outcome.

Topics: Adult; Amniotic Fluid; Enterocolitis, Necrotizing; Female; Humans; Hypoxia-Ischemia, Brain; Infant, Newborn; Male; Meconium; Meconium Aspiration Syndrome; Pregnancy; Respiratory Distress Syndrome, Newborn

Topics: Humans; Infant; Infant, Newborn; Intubation, Intratracheal; Meconium; Meconium Aspiration Syndrome; Resuscitation

Nonsteroidal anti-inflammatory drugs, such as selective phosphodiesterase type 4 (PDE4) inhibitors have potential anti-inflammatory and respiratory smooth muscle relaxation effects. This study aimed to investigate the pathophysiological effects of an intravenous PDE4 inhibitor (rolipram) and surfactant lavage (SL) in a newborn piglet model of meconium aspiration syndrome (MAS).. MAS was induced in 25 newborn piglets, which were randomly divided into control and four SL treatment groups administered with different doses of intravenous rolipram (0, 0.1, 0.5, and 1 mg/kg). Cardiopulmonary variables were monitored and recorded. The experimental time was 4 hours. Serial blood was drawn for blood gas and biomarker analyses. Lung tissue was examined for histological analysis.. All SL-treated groups revealed improved oxygenation during the 4-hour experiments and had significantly lower peak inspiratory pressure levels than the control group at the end of experiments. All SL plus rolipram-treated groups exhibited significantly higher lung compliance than the control group. However, the animals receiving high-dose (0.5 and 1.0 mg/kg) rolipram demonstrated significantly elevated heart rates. Lung histology of the nondependent sites revealed significantly lower lung injury scores in all SL-treated groups compared with that in the control group, but there were no differences among the rolipram-treated groups.. In addition to SL, intravenous PDE4 inhibitors may further improve lung compliance in treating MAS; however, it is necessary to consider cardiovascular adverse effects, primarily tachycardia. Further investigations are required before the clinical application of intravenous PDE4 inhibitor as an anti-inflammatory agent to treat severe MAS.

Topics: Administration, Intravenous; Animals; Animals, Newborn; Bronchoalveolar Lavage; Combined Modality Therapy; Humans; Lung; Lung Compliance; Meconium; Meconium Aspiration Syndrome; Phosphodiesterase 4 Inhibitors; Rolipram; Surface-Active Agents; Swine; Tachycardia

The immediate delivery room (DR) management of non-vigorous (NV) infants with meconium stained amniotic fluid (MSAF) is controversial. A recent ILCOR suggestion is not to perform routine direct laryngoscopy (DL) with or without tracheal suctioning in NV infants. Our practice is to perform DL and endotracheal (ET) suctioning in targeted NV infants. The study objective was to describe the perinatal characteristics and DR Management of infants born through MSAF and admitted to the neonatal intensive care unit (NICU).. Retrospective study evaluating the DR management of infants >35 weeks delivered through MSAF. Data retrieved included fetal heart rate abnormalities (FTHR), presence of thick/thin MSAF, DR management and postnatal course.. 118 infants were resuscitated and directly admitted to the NICU, including 58 intubated for meconium, 29 receiving immediate PPV (n = 25) or CPAP (n = 4) and 31 (17%) initially stable developed delayed respiratory symptoms and administered CPAP. Sixty-four (35.2%) infants initially stable in the DR were subsequently admitted to NICU. ET suctioning was performed in 58/182 infants with meconium obtained in 41/58; meconium aspiration syndrome (MAS) was diagnosed in 21 infants. ET suctioning was positive in 10/21 cases. FHRT abnormalities (n = 50) were noted with thick meconium and associated with a 2.8-fold increased risk for meconium below the cords, and 3.1-fold increased risk of MAS.. NV infants delivered through thick versus thin meconium were more likely to be intubated with a high yield of recovery. Serious pulmonary morbidity was uncommon. Most respiratory symptomatology were not related to MAS.

Topics: Delivery Rooms; Female; Humans; Infant; Infant, Newborn; Meconium; Meconium Aspiration Syndrome; Pregnancy; Retrospective Studies; Suction

To determine the perinatal outcome of labouring mothers with meconium-stained amniotic fluid (MSAF) compared with clear amniotic fluid at teaching referral hospital in urban Ethiopia.. A prospective cohort study was conducted among labouring mothers with meconium-stained amniotic fluid from July 1 to December 30, 2019. Data was collected with pretested structured questionnaires. A Chi-square test used to check statistical associations between variables. Those variables with a p-value of less than 0.05 were selected for cross-tabulation and binary logistic regression. P-value set at 0.05, and 95% CI was used to determine the significance of the association. Relative risk was used to determine the strength and direction of the association.. Among 438 participants, there where 75(52.1%) primigravida in a stained fluid group compared to112 (38.5%) of the non-stained fluid group. Labour was induced in 25 (17.4%) of the stained fluid group compared to 25(8.6%) of a non-stained fluid group and has a statistically significant association with meconium staining. The stained fluid group was twice more likely to undergo operative delivery compared with a non-stained fluid group. There were more low Apgar scores at birth (36.8% versus 13.2%), birth asphyxias (9% versus 2.4%), neonatal sepsis (1% versus 5.6%), neonatal death (1% versus 9%), and increased admissions to neonatal intensive care unit (6.2% versus 21.5%) among the meconium-stained group as compared to the non-stained group. Meconium aspiration syndrome was seen in 9(6.3%) of the stained fluid group.. Meconium-stained amniotic fluid is associated with increased frequency of operative delivery, birth asphyxia, neonatal sepsis, and neonatal intensive care unit admissions compared to clear amniotic fluid.

Topics: Adult; Amnion; Amniotic Fluid; Apgar Score; Asphyxia Neonatorum; Ethiopia; Female; Hospitals; Humans; Infant, Newborn; Infant, Newborn, Diseases; Intensive Care Units, Neonatal; Labor, Obstetric; Male; Meconium; Meconium Aspiration Syndrome; Mothers; Parturition; Pregnancy; Pregnancy Complications; Prospective Studies; Referral and Consultation; Young Adult

We provide the first complete biophysical study of surfactant by captive bubble surfactometry from a neonate with meconium-stained amniotic fluid under controlled whole body hypothermia. Surfactant function improves after 48 hours of hypothermia, as surfactant cholesterol decreases. These findings partially explain positive effect of hypothermia on respiratory outcomes during meconium aspiration syndrome. A larger study including several neonates with or without lung disease is being conducted to better define the effect of hypothermia on surfactant function.

Topics: Amniotic Fluid; Humans; Hypothermia; Hypothermia, Induced; Infant, Newborn; Meconium; Meconium Aspiration Syndrome; Surface-Active Agents

Topics: Amniotic Fluid; Child; Delivery Rooms; Humans; Infant, Newborn; Meconium; Meconium Aspiration Syndrome; Neonatologists; Pediatrics; Pregnancy

Meconium passage during labour is a quite common finding. Studies describing correlation between meconium stained liquor, fetal distress and specific placental pathology are sparse. This case control study had been designed to ascertain these lacunae of knowledge.. Placentae from 41 cases of otherwise uncomplicated antenatal and intranatal pregnancies with meconium stained liquor at 37 completed weeks of gestation were studied, both grossly and microscopically, comparing them with controls of 41 cases of clear liquor. Apgar score of all newborns at 1 minute and 5 minutes were recorded and correlated with histopathological findings.. Both cases and controls were found to be age matched. Meconium stained liquor was associated with more caesarian section than the clear ones. Significant correlation was found with meconium stained liquor and low Apgar scores. Histopathology of placenta revealed many statistically significant associations between specific placental histopathology in meconium stained liquor and depressed Apgar score. Evidence of placental vasculopathy rather than meconium induced placental damage came out as the potential culprit in causing a low Apgar score in this case control study.. Placental vascular changes have a role in meconium staining of liquor. If timely interventions are taken, the chance of development of fetal distress is low.

Topics: Adult; Amniotic Fluid; Apgar Score; Birth Weight; Case-Control Studies; Cesarean Section; Emergencies; Female; Fetal Blood; Fetal Distress; Fetal Mortality; Gestational Age; Humans; Hydrogen-Ion Concentration; Infant, Newborn; Meconium; Meconium Aspiration Syndrome; Morbidity; Placenta; Pregnancy; Pregnancy Complications; Risk Factors; Young Adult

Pancreatic digestive enzymes present in meconium might be responsible for meconium-induced lung injury. The local Renin Angiotensin System plays an important role in lung injury and inflammation. Particularly, angiotensin converting enzyme-2 (ACE-2) has been identified as a protective lung enzyme against the insult. ACE-2 converts pro-apoptotic Angiotensin II to anti-apoptotic Angiotensin 1-7. However, the effect of meconium on ACE-2 has never been studied before.. To study the effect of meconium on ACE-2, and whether inhibition of proteolytic enzymes present in the meconium reverses its effects on ACE-2.. Alveolar epithelial A549 cells were exposed to F-12 medium, 2.5% meconium, meconium + a protease inhibitor cocktail (PIc) and PIc alone for 16 h. At the end of incubation, apoptosis was measured with a nuclear fragmentation assay and cell lysates were collected for ACE-2 immunoblotting and enzyme activity.. Meconium caused a fourfold increase in apoptotic nuclei (p < 0.001). The pro-apoptotic effect of meconium can be reversed by PIc. Meconium reduced ACE-2 enzyme activity by cleaving ACE-2 into a fragment detected at ~ 37 kDa by immunoblot. PIc prevented the degradation of ACE-2 and restored 50% of ACE-2 activity (p < 0.05).. These data suggest that meconium causes degradation of lung protective ACE-2 by proteolytic enzymes present in meconium, since the effects of meconium can be reversed by PIc.

Topics: A549 Cells; Angiotensin-Converting Enzyme 2; Apoptosis; Enzyme Stability; Epithelial Cells; Humans; Meconium; Meconium Aspiration Syndrome; Peptide Hydrolases; Peptidyl-Dipeptidase A; Proteolysis; Pulmonary Alveoli

To determine frequency, stage and grade of placental histologic acute maternal inflammatory response (MIR) and fetal inflammatory response (FIR) in meconium-stained amniotic fluid (MSAF) in our predominantly African-American population.. Term placentas with MSAF (n = 310) were evaluated for MIR/FIR, including stage/grade, and compared with placentas with clear amniotic fluid (AF) (n = 250). MIR/FIR were also evaluated in thick compared to thin MSAF subgroups. Selected demographic and clinical features were compared.. MIR and FIR were present in 57.7 and 40.3% of the MSAF compared to 44.0 and 29.2% of the clear AF group, respectively (p = .001 and .008). MIR with FIR was present in 35.8% of the MSAF compared to 25.2% of the clear AF group (p = .008); however, there was no significant difference in frequency of MIR without FIR between groups. There was no significant difference in frequency of MIR/FIR in thick compared to thin MSAF; however, thick MSAF was associated with higher FIR stage compared to thin MSAF (29.2 versus 5.4%, p = .004). This association was not seen with MIR stage or MIR/FIR grade.. Histologic MIR and FIR are frequent findings in MSAF. Thick MSAF is associated with higher FIR stage when compared to thin MSAF.

Topics: Adult; Amniotic Fluid; Black or African American; Case-Control Studies; Chorioamnionitis; Female; Humans; Infant, Newborn; Meconium; Meconium Aspiration Syndrome; Placenta; Pregnancy; Retrospective Studies

Meconium aspiration syndrome (MAS) is a severe lung condition affecting newborns and it can lead to a systemic inflammatory response. We previously documented complement activation and cytokine release in a piglet MAS model. Additionally, we showed ex vivo that meconium-induced inflammation was dependent on complement and Toll-like receptors.. To assess the efficacy of the combined inhibition of complement (C5) and CD14 on systemic inflammation induced in a forceful piglet MAS model.. Thirty piglets were randomly allocated to a treatment group receiving the C5-inhibitor SOBI002 and anti-CD14 (n = 15) and a nontreated control group (n = 15). MAS was induced by intratracheal meconium instillation, and the piglets were observed for 5 h. Complement, cytokines, and myeloperoxidase (MPO) were measured by ELISA.. SOBI002 ablated C5 activity and the formation of the terminal complement complex in vivo. The combined inhibition attenuated the inflammasome cytokines IL-1β and IL-6 by 60 (p = 0.029) and 44% (p = 0.01), respectively, and also MPO activity in the bronchoalveolar fluid by 42% (p = 0.017). Ex vivo experiments in human blood revealed that the combined regimen attenuated meconium-induced MPO release by 64% (p = 0.008), but there was only a negligible effect with single inhibition, indicating a synergic cross-talk between the key molecules C5 and CD14.. Combined inhibition of C5 and CD14 attenuates meconium-induced inflammation in vivo and this could become a future therapeutic regimen for MAS.

Topics: Animals; Animals, Newborn; Complement Activation; Complement C5; Cytokines; Humans; Inflammation; Lipopolysaccharide Receptors; Meconium; Meconium Aspiration Syndrome; Random Allocation; Swine

To assess the success rate and main reasons for failure of intubation performed by medical trainees to suction meconium below the vocal cords in non-vigorous infants delivered at ≥36 week gestation.. We conducted a prospective cohort study involving 54 residents and nine neonatology fellows in a Canadian level 3 neonatal intensive care unit. Endotracheal intubation to suction meconium was performed using a videolaryngoscope, the video screen being covered during the procedure. All videos were reviewed by two experts blinded to the procedure and to the identity of the trainee.. Sixteen videos were available to review between July 2014 and March 2016. Intubation success rate assessed by the reviewers was 6%, compared with 21% as assessed by the trainees. The most common reasons for intubation failure were an improper view of the glottis (87%) and meconium or secretions obscuring the view (67%). 36 % of the time, the trainees identified different reasons for intubation failure than the reviewers.. Success rate of neonatal intubation to suction meconium was much lower than the success rate reported on infants without meconium. Teaching should be geared towards the most common reasons for intubation failure, possibly using video-based teaching.

Topics: Canada; Delivery, Obstetric; Female; Humans; Infant, Newborn; Intensive Care Units, Neonatal; Intubation, Intratracheal; Laryngoscopy; Meconium; Meconium Aspiration Syndrome; Needs Assessment; Neonatology; Pregnancy; Suction

The approach to the management of meconium-stained newborns in the delivery room has been changing for over 40 years. The goal is to prevent meconium aspiration syndrome (MAS) and complications related to MAS. For decades, airway obstruction was believed to be a major component of MAS and, consequently, suction maneuvers to remove meconium from the airways were recommended to decrease the frequency and severity of MAS. Initial recommendations were based on observational studies. However, the incidence of MAS and mortality related to MAS has declined since the 1970s, mostly because of a decrease in the number of postterm deliveries. Recently updated guidelines by the American Heart Association and the Neonatal Resuscitation Program have reflected the strength of evidence supporting tracheal intubation and suctioning for nonvigorous, meconium-stained newborns. This article examines practice change since the 1970s in the delivery room management of meconium-stained newborns and evaluates evidence behind the changes.

Topics: Amniotic Fluid; Education, Nursing; Humans; Infant, Newborn; Infant, Postmature; Intensive Care, Neonatal; Intubation, Intratracheal; Meconium; Meconium Aspiration Syndrome; Patient Care Management; Risk Factors

The approach to intrapartum and postnatal management of an infant born through meconium-stained amniotic fluid (MSAF) in the delivery room (DR) has changed several times over the last few decades, leading to confusion and anxiety among health care providers (nurses, nurse practitioners, respiratory therapists, midwives, and physicians). This article provides state-of-the-art insight into the evidence or lack thereof for the changes in guidelines.. To discuss the evidence for evolution of DR management of vigorous and nonvigorous infants born through any type of MSAF.. Review of guidelines from the Neonatal Resuscitation Program of the American Academy of Pediatrics and the American College of Obstetricians and Gynecologists, the International Liaison Committee on Resuscitation, Consensus on Science and Treatment Recommendations, and textbooks of neonatal resuscitation and research using MEDLINE via PubMed.. In pregnancies complicated by MSAF, intrapartum suctioning of the oro- and nasopharynx and postnatal intubation with tracheal suctioning of infants have been traditionally used to clear the airway and decrease meconium aspiration syndrome. The recommendations for these perinatal practices have changed several times due to some evidence that the procedures are not beneficial and may even be harmful.. Intrapartum suctioning and postnatal tracheal suctioning of infants (vigorous or nonvigorous) born through MSAF are not recommended. This is a "high-risk" delivery requiring 2 team members to be present at birth-one with full resuscitation skills including tracheal intubation.. Need to evaluate effects of discontinuing the practice of tracheal suctioning in nonvigorous infants on the incidence of meconium aspiration syndrome and neonatal mortality.

Topics: Amniotic Fluid; Delivery Rooms; Evidence-Based Practice; Female; Humans; Infant; Infant Mortality; Infant, Newborn; Intubation, Intratracheal; Meconium; Meconium Aspiration Syndrome; Perinatal Care; Postnatal Care; Practice Guidelines as Topic; Pregnancy; Resuscitation; Suction

Topics: Amniotic Fluid; Gastric Lavage; Humans; Infant, Newborn; Meconium; Meconium Aspiration Syndrome; Vomiting

Topics: Amniotic Fluid; Gastric Lavage; Humans; Infant; Infant, Newborn; Meconium; Meconium Aspiration Syndrome; Vomiting

Delivery room management of infants born via meconium-stained amniotic fluid (MSAF) is quite controversial. No study has tried to quantify the amount of meconium that can be aspirated from the trachea of a non-vigorous neonate born through MSAF.. To study the yield of meconium in non-vigorous neonates born through MSAF undergoing endotracheal (ET) suctioning.. This was a prospective observational study conducted from 1 March 2015 to 31 October 2015. A total of 760 neonates born through MSAF were enrolled. All non-vigorous neonates underwent ET suctioning. Meconium aspirated was quantified as nil (no meconium aspirated), insignificant (when only streaks of meconium were present in the ET tube), minimal (when the whole length of ET tube was filled with meconium) and significant (when the whole ET tube was filled with meconium and it poured into the suction tubing or when repeat suctioning was required).. The amount of meconium aspirated from the trachea was nil to insignificant in 46% of the neonates who underwent tracheal suctioning. Only 14.4% of the neonates had significant meconium aspirated from the trachea. Almost 46% of the non-vigorous infants underwent tracheal suctioning without any important amount of meconium being aspirated from the trachea.. The study further supports the recommendation put forth by the International Liaison Committee on Resuscitation (ILCOR) 2015 that selective intubation and tracheal suctioning of non-vigorous MSAF neonates might be of limited benefit.. ET: endotracheal; ILCOR: International Liaison Committee on Resuscitation; HIE: hypoxic ischaemic encephalopathy; LMIC: low- and middle-income countries; MAS: meconium aspiration syndrome; MSAF: meconium-stained amniotic fluid; NRP: neonatal resuscitation programme; PPHN: persistent pulmonary hypertension of the newborn; RCT: randomised controlled trial.

Topics: Amniotic Fluid; Female; Humans; Infant, Newborn; Intubation, Intratracheal; Male; Meconium; Meconium Aspiration Syndrome; Prospective Studies; Suction; Trachea

Topics: Adult; Amniotic Fluid; Apgar Score; Gestational Age; Humans; Infant, Newborn; Intensive Care Units, Neonatal; Israel; Jaundice, Neonatal; Meconium; Meconium Aspiration Syndrome; Patient Admission; Phototherapy; Respiration Disorders; Respiration, Artificial; Respiratory Distress Syndrome, Newborn; Retrospective Studies; Risk Factors; Sepsis; Tachypnea; Term Birth; Young Adult

This study aims to determine whether fetal meconium passage is associated with autism.. This retrospective birth cohort analysis of 9 945 896 children born in California 1991 to 2008 linked discharge diagnosis and procedure codes for prenatal stressors, meconium-stained amniotic fluid (MSAF) and meconium aspiration syndrome (MAS) with autism diagnoses for 47 277 children through 2012. We assessed the relative risk of autism by meconium status using logistic regression, adjusting for demographic and clinical features.. Children exposed to meconium (MSAF and MAS) were more likely to be diagnosed with autism in comparison with unexposed children (0.60% and 0.52%, vs 0.47%, respectively). In adjusted analyses, there was a small increase in autism risk associated with MSAF exposure (adjusted relative risk (aRR) 1.18, 95% confidence interval (CI) 1.12 to 1.25), and a marginal association that failed to achieve significance between MAS and autism (aRR 1.08, 95% CI 0.98 to 1.20).. Resuscitation of neonates with respiratory compromise from in utero meconium exposure may mitigate long-term neurodevelopmental damage.

Topics: Amniotic Fluid; Apgar Score; Autistic Disorder; California; Child, Preschool; Female; Gestational Age; Humans; Infant; Infant, Newborn; Logistic Models; Male; Meconium; Meconium Aspiration Syndrome; Psychiatric Status Rating Scales; Resuscitation; Retrospective Studies

Topics: Humans; Infant; Infant, Newborn; Intubation, Intratracheal; Meconium; Meconium Aspiration Syndrome; Pilot Projects; Suction; Trachea

Topics: Humans; Infant; Infant, Newborn; Intubation, Intratracheal; Meconium; Meconium Aspiration Syndrome; Suction; Trachea

In 2006, the American Academy of Pediatrics and the American Heart Association published the 2005 guidelines on neonatal resuscitation. Before the 2005 guidelines, management of a newborn with meconium-stained amniotic fluid included suctioning of the oropharynx and nasopharynx on the perineum after the delivery of the head but before the delivery of the shoulders. The 2005 guidelines did not support this practice because routine intrapartum suctioning does not prevent or alter the course of meconium aspiration syndrome in vigorous newborns. However, the 2005 guidelines did support intubation of the trachea and suctioning of meconium or other aspirated material from beneath the glottis in nonvigorous newborns. In 2015, the guidelines were updated. Routine intubation and tracheal suctioning are no longer required. If the infant is vigorous with good respiratory effort and muscle tone, the infant may stay with the mother to receive the initial steps of newborn care. If the infant born through meconium-stained amniotic fluid presents with poor muscle tone and inadequate breathing efforts, the initial steps of resuscitation should be completed under the radiant warmer. Appropriate intervention to support ventilation and oxygenation should be initiated as indicated for each infant. Infants with meconium-stained amniotic fluid should no longer routinely receive intrapartum suctioning, whether they are vigorous or not. In addition, meconium-stained amniotic fluid is a condition that requires the notification and availability of an appropriately credentialed team with full resuscitation skills, including endotracheal intubation. Resuscitation should follow the same principles for infants with meconium-stained fluid as for those with clear fluid.

Topics: Amniotic Fluid; Delivery, Obstetric; Female; Humans; Infant, Newborn; Meconium; Meconium Aspiration Syndrome; Pregnancy; Suction

In 2006, the American Academy of Pediatrics and the American Heart Association published the 2005 guidelines on neonatal resuscitation. Before the 2005 guidelines, management of a newborn with meconium-stained amniotic fluid included suctioning of the oropharynx and nasopharynx on the perineum after the delivery of the head but before the delivery of the shoulders. The 2005 guidelines did not support this practice because routine intrapartum suctioning does not prevent or alter the course of meconium aspiration syndrome in vigorous newborns. However, the 2005 guidelines did support intubation of the trachea and suctioning of meconium or other aspirated material from beneath the glottis in nonvigorous newborns. In 2015, the guidelines were updated. Routine intubation and tracheal suctioning are no longer required. If the infant is vigorous with good respiratory effort and muscle tone, the infant may stay with the mother to receive the initial steps of newborn care. If the infant born through meconium-stained amniotic fluid presents with poor muscle tone and inadequate breathing efforts, the initial steps of resuscitation should be completed under the radiant warmer. Appropriate intervention to support ventilation and oxygenation should be initiated as indicated for each infant. Infants with meconium-stained amniotic fluid should no longer routinely receive intrapartum suctioning, whether they are vigorous or not. In addition, meconium-stained amniotic fluid is a condition that requires the notification and availability of an appropriately credentialed team with full resuscitation skills, including endotracheal intubation. Resuscitation should follow the same principles for infants with meconium-stained fluid as for those with clear fluid.

Topics: Amniotic Fluid; Humans; Infant, Newborn; Intubation, Intratracheal; Meconium; Meconium Aspiration Syndrome; Patient Care Team; Perinatal Care; Resuscitation; Suction

This study aims to determine the impact of meconium-stained amniotic fluid (MSAF) in low-risk pregnancies at term on pregnancy outcome.. A retrospective cohort study of women with MSAF during labor who delivered in a tertiary hospital at 37 to 41(+6) weeks of gestation (2007-2013). Exclusion criteria included: multiple gestations, noncephalic presentation, fetal structural/chromosomal anomalies, hypertensive disorders, diabetes, oligohydramnios, or small for gestational age. Pregnancy outcome of women with MSAF (N = 4,893) was compared with a control group of women without MSAF (N = 39,651). Neonatal respiratory morbidity was defined as the presence of any of the following: respiratory distress syndrome, transient tachypnea of the newborn, meconium aspiration syndrome, or need for ventilatory support.. Overall, 10.9% of low-risk pregnancies at term were diagnosed with MSAF. Compared with the controls, women with MSAF had higher rates of nulliparity, gestational age at delivery ≥ 41 weeks, induction of labor, nonreassuring fetal heart rate, and operative deliveries. In multivariate analysis MSAF was associated with operative delivery (odds ratio [OR], 1.82; 95% confidence interval [CI], 1.63-2.09; p < 0.001), cesarean section (OR, 1.48; 95% CI, 1.31-1.69; p < 0.001), respiratory morbidity (OR, 4.74; 95% CI, 3.87-5.82; p < 0.001), and increased risk for short-term neonatal morbidity.. MSAF is associated with a higher rate of adverse perinatal outcome even in low-risk pregnancies at term.

Topics: Adult; Amniotic Fluid; Apgar Score; Case-Control Studies; Cesarean Section; Female; Gestational Age; Heart Rate, Fetal; Humans; Infant, Newborn; Logistic Models; Meconium; Meconium Aspiration Syndrome; Multivariate Analysis; Parity; Pregnancy; Pregnancy Outcome; Retrospective Studies; Term Birth; Tertiary Care Centers

Topics: Animals; Humans; Infant, Newborn; Inflammation; Intensive Care, Neonatal; Meconium; Meconium Aspiration Syndrome; Systemic Inflammatory Response Syndrome

Meconium aspiration syndrome (MAS) is a serious condition, which can be treated with exogenous surfactant and mechanical ventilation. However, meconium-induced inflammation, lung edema and oxidative damage may inactivate delivered surfactant and thereby reduce effectiveness of the therapy. As we presumed that addition of anti-inflammatory agent into the surfactant may alleviate inflammation and enhance efficiency of the therapy, this study was performed to evaluate effects of surfactant therapy enriched with budesonide versus surfactant-only therapy on markers of oxidative stress in experimental model of MAS. Meconium suspension (25 mg/ml, 4 ml/kg) was instilled into the trachea of young rabbits, whereas one group of animals received saline instead of meconium (C group, n = 6). In meconium-instilled animals, respiratory failure developed within 30 min. Then, meconium-instilled animals were divided into 3 groups according to therapy (n = 6 each): with surfactant therapy (M + S group), with surfactant + budesonide therapy (M + S + B), and without therapy (M group). Surfactant therapy consisted of two bronchoalveolar lavages (BAL) with diluted surfactant (Curosurf, 5 mg phospholipids/ml, 10 ml/kg) followed by undiluted surfactant (100 mg phospholipids/kg), which was in M + S + B group enriched with budesonide (Pulmicort, 0.5 mg/ml). Animals were oxygen-ventilated for additional 5 hours. At the end of experiment, blood sample was taken for differential white blood cell (WBC) count. After euthanizing animals, left lung was saline-lavaged and cell differential in BAL was determined. Oxidative damage, i.e. oxidation of lipids (thiobarbituric acid reactive substance (TBARS) and conjugated dienes) and proteins (dityrosine and lysine-lipoperoxidation products) was estimated in lung homogenate and isolated mitochondria. Total antioxidant capacity was evaluated in lung homogenate and plasma. Meconium instillation increased transmigration of neutrophils and production of free radicals compared to controls (P < 0.05). Surfactant therapy, but particularly combined surfactant + budesonide therapy reduced markers of oxidative stress versus untreated animals (P < 0.05). In conclusion, budesonide added into surfactant enhanced effect of therapy on oxidative damage of the lung.

Topics: Animals; Anti-Inflammatory Agents; Antioxidants; Bronchoalveolar Lavage Fluid; Budesonide; Disease Models, Animal; Female; Free Radicals; Inflammation; Lung; Lung Injury; Male; Meconium; Meconium Aspiration Syndrome; Neutrophils; Oxidative Stress; Pulmonary Edema; Pulmonary Surfactants; Rabbits; Trachea

The exact pathophysiology of meconium passage into the amniotic fluid is unknown, but it is frequently associated with fetal hypoxia. The mean platelet volume (MPV) seems to be a marker of platelet production and consumption and may be related to the severity of some diseases associated with bone marrow, hypoxia, and perinatal infections. We aimed to investigate the association between MPV levels and meconium-stained amniotic fluid (MSAF) in infants.. MPV, serum-reactive protein and hemoglobin levels, and leukocyte and thrombocyte counts were measured in 106 infants with MSAF and a comparison group of 78 healthy control infants.. The mean MPV values of the infants with MSAF were statistically significantly lower than those of the control group (p < 0.001). There was no statistically significant difference in the hemoglobin levels or leukocyte and thrombocyte counts in the study group compared to the control group (p > 0.05). There was also no statistically significant difference in the MPV levels of the infants with meconium aspiration syndrome (MAS) compared to the infants with MSAF without MAS (p = 0.107). The optimal cut-off value for the MPV was 9.90 fl (area under the curve [AUC: 0.788]) in the infants with MSAF, with a sensitivity of 78.1% and specificity of 74.3%.. Our data suggest that the MPV levels of infants with MSAF were significantly lower than those of healthy infants. This might be associated with a hypoxic process. However, the MPV levels of infants with MSAF and MAS were statistically similar. Thus, the MPV level could not be used to detect patients with or without severe disease.

Topics: Amniotic Fluid; Biomarkers; Female; Humans; Infant; Infant, Newborn; Mean Platelet Volume; Meconium; Meconium Aspiration Syndrome; Pregnancy

Anti-inflammatory drugs are increasingly used for treatment of neonatal meconium aspiration syndrome (MAS), but their adverse effects are poorly known. Therefore, the aim of this study was to evaluate the effects of the antioxidant N-acetylcysteine on cardiovascular parameters in an animal model of MAS. Oxygen-ventilated rabbits were intratracheally instilled 4 mL/kg of meconium suspension (25 mg/mL) or saline. Thirty minutes later, meconium-instilled animals were given N-acetylcysteine (10 mg/kg, i.v.) or the same volume of saline. Changes in cardiovascular parameters (blood pressure, heart rate, and heart rate variability) were recorded over a 5-min course of solution administration, over 5 min after its end, and then hourly for 5 h. Oxidation markers (thiobarbituric acid-reactive substances (TBARS) and total antioxidant status) and aldosterone, as a non-specific marker of cardiovascular injury, were determined in plasma. Meconium instillation did not evoke any significant cardiovascular changes, but induced oxidative stress and elevated plasma aldosterone. N-acetylcysteine significantly reduced the mentioned markers of injury. However, its administration was associated with short-term increases in blood pressure and in several parameters of heart rate variability. Considering these effects of N-acetylcysteine, its intravenous administration in newborns with MAS should be carefully monitored.

Topics: Acetylcysteine; Acute Lung Injury; Aldosterone; Animals; Anti-Inflammatory Agents; Antioxidants; Blood Pressure; Disease Models, Animal; Heart Rate; Humans; Infant, Newborn; Injections, Intravenous; Intubation, Intratracheal; Lung; Meconium; Meconium Aspiration Syndrome; Oxidative Stress; Rabbits; Respiration, Artificial; Thiobarbituric Acid Reactive Substances

Meconium aspiration in newborns causes lung inflammation and injury, which may lead to meconium aspiration syndrome (MAS). In this study, the effect of the antioxidant N-acetylcysteine on respiratory and inflammatory parameters were studied in a model of MAS. Oxygen-ventilated rabbits were intratracheally given 4 mL/kg of meconium (25 mg/mL) or saline. Thirty minutes later, meconium-instilled animals were administered N-acetylcysteine (10 mg/kg; i.v.), or were left without treatment. The animals were oxygen-ventilated for additional 5 h. Ventilatory pressures, oxygenation, right-to-left pulmonary shunts, and leukocyte count were measured. At the end of experiment, trachea and lung were excised. The left lung was saline-lavaged and a total and differential count of cells in bronchoalveolar lavage fluid (BAL) was determined. Right lung tissue strips were used for detection of lung edema (expressed as wet/dry weight ratio) and peroxidation (expressed by thiobarbituric acid-reactive substances, TBARS). In lung and tracheal strips, airway reactivity to acetylcholine was measured. In addition, TBARS and total antioxidant status were determined in the plasma. Meconium instillation induced polymorphonuclear-derived inflammation and oxidative stress. N-acetylcysteine improved oxygenation, reduced lung edema, decreased polymorphonuclears in BAL fluid, and diminished peroxidation and meconium-induced airway hyperreactivity compared with untreated animals. In conclusion, N-acetylcysteine effectively improved lung functions in an animal model of MAS.

Topics: Acetylcysteine; Acute Lung Injury; Animals; Anti-Inflammatory Agents; Antioxidants; Bronchoalveolar Lavage Fluid; Disease Models, Animal; Humans; Infant, Newborn; Injections, Intravenous; Intubation, Intratracheal; Leukocyte Count; Lipid Peroxidation; Lung; Meconium; Meconium Aspiration Syndrome; Oxidative Stress; Pulmonary Edema; Rabbits; Respiration, Artificial; Thiobarbituric Acid Reactive Substances; Trachea

Topics: Adult; Female; Fetal Diseases; Humans; Imaging, Three-Dimensional; Infant, Newborn; Infant, Newborn, Diseases; Inflammatory Bowel Diseases; Meconium; Meconium Aspiration Syndrome; Peritonitis; Pregnancy; Ultrasonography, Prenatal

Since inflammation and oxidative stress are fundamental in the pathophysiology of neonatal meconium aspiration syndrome (MAS), various anti-inflammatory drugs have been used in experimental and clinical studies on MAS. This pilot study evaluated therapeutic potential of N-acetylcysteine in modulation of meconium-induced inflammation and oxidative lung injury. Oxygen-ventilated adult rabbits were intratracheally given 4 ml/kg of meconium (25 mg/ml) or saline (Sal, n = 6). Thirty minutes later, meconium-instilled animals were treated with intravenous N-acetylcysteine (10 mg/kg, Mec + NAC, n=6) or were non-treated (Mec, n = 6). All animals were oxygen-ventilated for additional 5 hours. Total and differential blood leukocyte counts were determined at baseline, and at 1, 3 and 5 h of the treatment. After sacrificing animals, left lung was saline-lavaged and total and differential cell counts in the bronchoalveolar lavage fluid were determined. Right lung was used for biochemical analyses and for estimation of wet-dry weight ratio. In lung tissue homogenate, thiobarbituric acid-reactive substances (TBARS), dityrosine, lysine-lipid peroxidation (LPO) products, and total antioxidant status (TAS) were detected. In isolated lung mitochondria, TBARS, dityrosine, lysine-LPO products, thiol group content, conjugated dienes, and activity of cytochrome c oxidase were estimated. To evaluate systemic effects of meconium instillation and NAC treatment, TBARS and TAS were determined also in plasma. To evaluate participation of eosinophils in the meconium-induced inflammation, eosinophil cationic protein (ECP) was detected in plasma and lung homogenate. Meconium instillation increased oxidation markers and ECP in the lung and decreased TAS (all P<0.05). NAC treatment reduced ECP and oxidation markers (all P<0.05, except of dityrosine in homogenate and conjugated dienes in mitochondria) and prevented a decrease in TAS (P<0.01) in lung homogenate compared to Mec group. In plasma, NAC decreased TBARS (P<0.001) and ECP, and increased TAS (both P<0.05) compared to Mec group. Concluding, N-acetylcysteine diminished meconium-induced inflammation and oxidative lung injury.

Topics: Acetylcysteine; Age Factors; Animals; Antioxidants; Biomarkers; Disease Models, Animal; Humans; Infant, Newborn; Inflammation Mediators; Leukocytes; Lipid Peroxidation; Lung; Lung Injury; Meconium; Meconium Aspiration Syndrome; Mitochondria; Oxidative Stress; Pneumonia; Pulmonary Edema; Rabbits; Thiobarbituric Acid Reactive Substances; Time Factors

There is sufficient evidence to support the practice of optimal cord clamping in normal labour and birth. In this paper, the physiology of meconium stained liquor (MSL), meconium aspiration syndrome and the practice of optimal cord clamping in babies born through MSL, is discussed. Guidelines suggest not stimulating babies born through MSL, at birth, to avoid aspiration. However, the obvious stimulation resulting from early clamping and cutting the cord, leaves a baby with no choice but to inhale, but this appears to be overlooked in practice. Midwives in their role as supporters of normal physiology are in a position to question this routine intervention in the absence of any evidence to support it.

Topics: Delivery, Obstetric; Female; Humans; Meconium; Meconium Aspiration Syndrome; Obstetric Labor Complications; Pregnancy; Pregnancy Outcome; Umbilical Cord

To determine the association of cord arterial blood pH with neonatal outcome in cases of intrapartum fetal hypoxia.. Descriptive analytical study.. Gynaecology Unit-II, Civil Hospital, Karachi, from September 2011 to November 2012.. All singleton cephalic fetuses at term gestation were included in the study. Those with any anomaly, malpresentation, medical disorders, maternal age < 18 years, multiple gestation and ruptured membranes were excluded. Patients with abnormal cardiotocography and/or meconium stained liquor were enrolled as index case and immediate next delivery with no such signs as a control. Demographic characteristics, pH level < or > 7.25, neonatal outcome measures (healthy, NICU admission or neonatal death), color of liquor and mode of delivery recorded on predesigned proforma. Statistical analysis performed by SPSS 16 by using independent-t test or chi-square test and ANOVA test as needed.. A total of 204 newborns were evaluated. The mean pH level was found to be significantly different (p=0.007) in two groups. The pH value 7.25 had significant association (p < 0.001) with the neonatal outcome. However, the association of neonatal outcome with severity of acidemia was not found to be significant. Grading of Meconium Stained Liquor (MSL) also did not relate positively with pH levels as 85.7% of grade I, 68.9% of grade II and 59.4% of grade III MSLhad pH > 7.25. Majority (63.6%) cases needed caesarean section as compared to 31.4% controls.. There is a significant association of cord arterial blood pH at birth with neonatal outcome at pH < or > 7.25; but below the level of pH 7.25 it is still inconclusive.

Topics: Acid-Base Imbalance; Apgar Score; Cardiotocography; Female; Fetal Blood; Fetal Hypoxia; Fetus; Humans; Hydrogen-Ion Concentration; Infant, Newborn; Male; Meconium; Meconium Aspiration Syndrome; Pregnancy; Pregnancy Outcome; Prospective Studies

Topics: Amniotic Fluid; Female; Fetal Development; Fetal Membranes, Premature Rupture; Humans; Infant, Newborn; Meconium; Meconium Aspiration Syndrome; Models, Biological; Pregnancy

Category II fetal heart rate (FHR) tracings are considered indeterminate; thus, improved risk stratification of category II FHR tracings is needed. We estimated whether the presence of meconium increased the risk of adverse neonatal outcomes.. This study was conducted within a prospective cohort of 5000 women with singleton pregnancies who were admitted in labor at term. Pregnancies with category II FHR in the 60 minutes before delivery were included. FHR data were extracted by trained nurses who were blinded to clinical outcome. The exposure was the presence of meconium. The primary outcome was a composite neonatal morbidity defined as ≥1 of the following: neonatal death, neurologic morbidity, respiratory morbidity, hypotension that required treatment, and sepsis. Secondary outcomes were nursery admission, cord pH, 5-minute Apgar score, and components of the composite. Logistic regression was used to adjust for confounders.. Of the 3257 women with category II FHR tracings, 693 women (21.3%) had meconium, and 2564 women (78.7%) did not. Meconium was associated with higher risk of the composite morbidity (adjusted odds ratio, 2.49; 95% confidence interval, 1.78-3.48) and increased risks of the secondary outcomes. The associations remained significant when infants with meconium aspiration syndrome were excluded. Thick meconium was associated significantly with the composite morbidity.. The presence of meconium is associated with an increased risk of neonatal morbidity in women with category II FHR pattern. This clinical factor may assist clinicians in managing category II FHR patterns in labor.

Topics: Adult; Amniotic Fluid; Cardiotocography; Female; Heart Rate, Fetal; Humans; Hypotension; Infant, Newborn; Infant, Newborn, Diseases; Logistic Models; Meconium; Meconium Aspiration Syndrome; Multivariate Analysis; Obstetric Labor Complications; Odds Ratio; Perinatal Death; Pregnancy; Prospective Studies; Risk Assessment; Risk Factors; Sepsis; Young Adult

Topics: Amniotic Fluid; Equipment Design; Humans; Infant, Newborn; Meconium; Meconium Aspiration Syndrome; Suction

Topics: Female; Humans; Infant, Premature; Infant, Premature, Diseases; Meconium; Meconium Aspiration Syndrome; Nurse's Role; Nursing Methodology Research; Obstetric Labor Complications; Perinatal Care; Pregnancy

A variety of suction catheters (type, size and design) are recommended for oropharyngeal suctioning of meconium during newborn resuscitation, but it is not known which performs best. In this study we compared different sizes of soft catheters, the Yankauer (YK) and the portable bulb syringe (BS), in suctioning a solution of varying viscosity.. Simulated meconium (SM) was made using commercial canned pea soup in two strengths, full-strength thick-particulate (TP) and 50% strained soup diluted with water, that is, thin-non-particulate (TnP), with saline as a control. A 20 ml aliquot of solution was suctioned over 5 s with each device using an electrical suction pump set at two different pressures, 100 and 150 mm Hg (21 kpa). In addition, the negative pressure of five BSs was measured in order to compare generated pressures with the alternative devices.. The YK and BS suctioned almost 100% of saline, while the 6F and 8F catheters suctioned 50% and 75% saline, respectively. The YK suctioned 100% of TnP, saline and 30% of TP. At reduced suction pressures (100 and 50 mm Hg) the YK also suctioned all TnP. The 12F and 14F catheters suctioned a minimal amount of TP, whereas YK was the most efficient, suctioning 30% of TP. The mean negative pressure generated with five BSs was 78 and 71 mm Hg by a male and female operator, respectively.. The YK and BS outperform the catheters in suctioning SM. The YK is the best for TP, but all devices perform poorly in suctioning fluid of this consistency.

Topics: Catheterization; Catheters; Female; Humans; Infant, Newborn; Male; Meconium; Meconium Aspiration Syndrome; Resuscitation; Suction

Meconium aspiration syndrome (MAS) remains a frequent cause of morbidity and mortality in term newborns. Our objective was to compare two modes of high-frequency ventilation, high-frequency oscillation (HFOV), and high-frequency percussive ventilation (HFPV) with conventional mechanical ventilation (CMV) in a piglet model of MAS.. Fifteen newborn piglets were anesthetized, paralyzed, and intubated. Following the instillation of a 3 ml/kg solution of meconium diluted to 30%, the piglets were randomized to one of three groups: high-frequency oscillation (HFOV; Sensormedics®), HFPV (Percussionaire®), or CMV (Siemens®). Animals were ventilated for 6 hr to maintain arterial blood gases within a normal range, that is, pH 7.35-7.45, PaO(2) 10-16 kPa, PaCO(2) 4-6.6 kPa. Arterial blood gas measurements, dynCrs and dynRrs, ventilator settings, and vital signs (heart rate, arterial blood pressure, transcutaneous pulse oxygen saturation, and temperature) were collected at 30, 60, 90, 120, 180, 240, 300, and 360 min after meconium instillation. Oxygenation index (OI) ([(fraction of inspired oxygen)(mean airway pressure)(100)]/PaO(2) ), mean airway pressure, dynamic lung function, secretions cleared and histological alterations were studied in all groups.. Mean airway pressure and OI were significantly lower in the CV and HFPV groups compared to the HFOV group (P < 0.05). There was no significant difference between groups regarding lung function, amount of secretions and histological alterations.. In our model of MAS in piglets, whilst effective gas exchange with a lower mean airway pressure was possible with both CMV and HFPV compared with HFOV there was no apparent difference in lung histology or secretions.

Topics: Animals; Blood Gas Analysis; Disease Models, Animal; High-Frequency Ventilation; Humans; Infant, Newborn; Lung; Meconium; Meconium Aspiration Syndrome; Random Allocation; Respiratory Function Tests; Swine; Treatment Outcome; Vital Signs

Inflammation, oxidation, lung edema, and other factors participate in surfactant dysfunction in meconium aspiration syndrome (MAS). Therefore, we hypothesized that anti-inflammatory treatment may reverse surfactant dysfunction in the MAS model. Oxygen-ventilated rabbits were given meconium intratracheally (25 mg/ml, 4 ml/kg; Mec) or saline (Sal). Thirty minutes later, meconium-instilled animals were treated by glucocorticoids budesonide (0.25 mg/kg, i.t.) and dexamethasone (0.5 mg/kg, i.v.), or phosphodiesterase inhibitors aminophylline (2 mg/kg, i.v.) and olprinone (0.2 mg/kg, i.v.), or the antioxidant N-acetylcysteine (10 mg/kg, i.v.). Healthy, non-ventilated animals served as controls (Con). At the end of experiments, left lung was lavaged and a differential leukocyte count in sediment was estimated. The supernatant of lavage fluid was adjusted to a concentration of 0.5 mg phospholipids/ml. Surfactant quality was evaluated by capillary surfactometer and expressed by initial pressure and the time of capillary patency. The right lung was used to determine lung edema by wet/dry (W/D) weight ratio. Total antioxidant status (TAS) in blood plasma was evaluated. W/D ratio increased and capillary patency time shortened significantly, whereas the initial pressure increased and TAS decreased insignificantly in Sal vs. Con groups. Meconium instillation potentiated edema formation and neutrophil influx into the lungs, reduced capillary patency and TAS, and decreased the surfactant quality compared with both Sal and Con groups (p > 0.05). Each of the anti-inflammatory agents reduced lung edema and neutrophil influx into the lung and partly reversed surfactant dysfunction in the MAS model, with a superior effect observed after glucocorticoids and the antioxidant N-acetylcysteine.

Topics: Acetylcysteine; Acute Lung Injury; Aminophylline; Animals; Anti-Inflammatory Agents; Antioxidants; Bronchoalveolar Lavage Fluid; Budesonide; Dexamethasone; Disease Models, Animal; Humans; Imidazoles; Infant, Newborn; Leukocyte Count; Lung; Meconium; Meconium Aspiration Syndrome; Neutrophils; Oxidative Stress; Phosphodiesterase Inhibitors; Pulmonary Edema; Pulmonary Surfactants; Pyridones; Rabbits

As inflammation plays an important role in the pathogenesis of neonatal meconium aspiration syndrome (MAS), anti-inflammatory agents including inhibitors of phosphodiesterases (PDE) are increasingly used in the treatment. To evaluate side effects of PDE inhibitors, this study analyzed changes in blood pressure, heart rate (HR) and heart rate variability (HRV) during and after intravenous aminophylline in the animal model of MAS. Oxygen-ventilated rabbits were given meconium intratracheally (25 mg/ml, 4 ml/kg) or saline. Thirty minutes later, the animals were treated by intravenous aminophylline (Syntophyllin, 2 mg/kg) or saline (sham-treated controls). A second dose of the treatment was given 2 h later. During (5 min) and immediately after (5 min) the treatment, and during 5 h after the treatment, mean blood pressure in the femoral artery (MAP), HR and HRV were evaluated. In meconium-instilled animals, increases in MABP, HR, and HRV were observed already 5 min after aminophylline administration, while in saline-instilled animals aminophylline increased HR and caused inconsistant changes in HRV parameters compared to sham-treated animals. Within 5 h after the treatment administration, MAP, HR, and HRV parameters gradually returned to the initial values. Concluding, intravenous aminophylline may lead to acute cardiovascular changes. Thus, if aminophylline is used for treatment of MAS, its possible cardiovascular effects should be considered, particularly in patients with cardiovascular instability.

Topics: Aminophylline; Animals; Blood Pressure; Bronchodilator Agents; Cardiovascular System; Disease Models, Animal; Heart Rate; Humans; Infant, Newborn; Lung; Meconium; Meconium Aspiration Syndrome; Phosphodiesterase Inhibitors; Rabbits

The aim of this study was to compare cord blood S100B levels and cord blood gas parameters of term infants with meconium-stained amniotic fluid (MSAF) to those infants with clear amniotic fluid.. Term pregnant women at an active phase of labor and having MSAF were defined as the study group (n = 35) and pregnant women with clear amniotic fluid, and matched for age, parity, and gestational age were defined as the control group (n = 35). Cord blood S100B levels and gas parameters were measured.. LogS100B values of study and control groups were 2.40 ± 0.21 and 2.43 ± 0.29 pg/ml, respectively. The difference was not statistically significant (p = 0.675). LogS100B levels slightly increased as meconium thickened. (2.32 ± 0.16, 2.41 ± 0.17, and 2.44 ± 0.28 pg/ml, respectively). However, no difference was found between groups (p = 0.438). Moreover, the study group had a statistically lower HCO(3) level (21.80 vs 23.60 mmol/l) and a higher rate of base deficit (4.85 vs 3.25 mmol/l) than the control group. However, median HCO(3) and base deficit values were within normal limits in both groups.. The present study showed that cord blood S100B levels of infants born through MSAF were not different from those with clear amniotic fluid. This finding suggests that MSAF, regardless of its thickness, may not be related to brain damage in low risk term pregnancies.

Topics: Adult; Amniotic Fluid; Bicarbonates; Blood Gas Analysis; Case-Control Studies; Female; Fetal Blood; Humans; Infant, Newborn; Meconium; Meconium Aspiration Syndrome; Nerve Growth Factors; Pregnancy; Risk Factors; S100 Calcium Binding Protein beta Subunit; S100 Proteins; Term Birth; Young Adult

This study aimed to find out incidence, predictors, onset and severity of respiratory distress including meconium aspiration syndrome (MAS) among vigorous neonates born through meconium stained amniotic fluid (MSAF), which may or may not be evident at birth.. Two hundred ninety vigorous neonates were studied. Data were collected on perinatal risk factors, clinical course and development of respiratory distress. Predictors of respiratory distress were identified by logistic regression and a score based on adjusted OR was assigned for each. Diagnostic performance of the score (0-24) was assessed on another 247 vigorous neonates using receiver operator characteristic analysis (ROC).. Respiratory distress developed in 97(33.4 %) infants, MAS in 75(25.9 %). The distress appeared within 12 h in 97.9 %, was severe in only 21.7 %. Of 10 risk factors significantly associated with respiratory distress, seven entered in regression analysis. Fetal distress(adj OR = 11.8; 95%CI = 6.2-22.5), prolonged labor(adj OR = 5.2; 95%CI = 2.5-10.7), and absent/poor cry(adj OR = 5.6; 95%CI = 2.4-13.3) were identified as independent predictors; each assigned a score of 12, 6 and 6, respectively. To predict respiratory distress, a cut-off score of 9 points had sensitivity-74.1 % (95%CI = 63.3 %-82.7 %), specificity-84.6 % (95 % CI = 77.9 %-89.6 %), positive predictive value- 71.6 % (95%CI = 60.8 %-80.4 %), negative predictive value- 86.2 % (95 % CI = 79.6 %-90.9 %), likelihood ratio (LR) + ve 4.8(95%CI = 3.3-7.0) and LR-ve 0.3(95%CI = 0.2-0.4).. Respiratory distress occurred in one third neonates, mostly had onset within 12 h of birth, and it was mild to moderate in majority. Fetal distress, prolonged labor, and absent/poor cry predicted respiratory distress and were validated. However, larger studies in different settings are required to confirm its utility.

Topics: Amniotic Fluid; Apgar Score; Female; Humans; Incidence; India; Infant, Newborn; Male; Meconium; Meconium Aspiration Syndrome; Predictive Value of Tests; Pregnancy; Prospective Studies; Respiratory Distress Syndrome, Newborn; Risk Factors

To develop the immunohistochemistry specific for meconium in the placenta, fetal membrane and umbilical cord.. We previously reported the specific presence of zinc coproporphyrin I (ZnCP-I) in human meconium and demonstrated the possible diagnostic use of an elevation in maternal plasma ZnCP-I levels in cases of amniotic fluid embolism. In this study, we developed a new specific monoclonal antibody for ZnCP-I and applied it to the immunostaining of meconium in the placenta, fetal membrane, and umbilical cord.. Immunoreactivity of ZnCP-I clearly and specifically identified meconium in the placenta, fetal membrane, and umbilical cord. It was especially useful in cases of severe chorioamnionitis to detect meconium in the macrophages surrounded by numerous neutrophils. In more than half of the cases, meconium was detected in clear amniotic fluid at delivery, suggesting previous exposure.. Immunohistochemical detection of ZnCP-I is a highly sensitive histological diagnosis of meconium.

Topics: Adult; Antibodies, Monoclonal; Antibody Specificity; Chorioamnionitis; Coproporphyrins; Embolism, Amniotic Fluid; Extraembryonic Membranes; Female; Humans; Immunohistochemistry; Infant, Newborn; Macrophages; Mass Screening; Meconium; Meconium Aspiration Syndrome; Neonatal Screening; Placenta; Pregnancy; Severity of Illness Index; Staining and Labeling; Umbilical Cord

To evaluate whether meconium-stained amniotic fluid (MSAF) is a risk factor for neonatal hypoglycemia. Retrospective recording of medical charts of full-term infants born following observation of meconium-stained amniotic fluid to examine glucose levels in the first hours of life. Out of 803 infants of the study group, 68 (8.5%) had glucose levels lower than 47 mg/dl. Most (6.7%) had mild hypoglycemia, and 14 (1.8%) had moderate or severe hypoglycemia (1.4% and 0.4% respectively). No infant developed clinical signs clearly related to hypoglycemia. Low-risk infants born following meconium-stained amniotic fluid are not at increased risk for neonatal hypoglycemia.

Topics: Amniotic Fluid; Blood Glucose; Comorbidity; Female; Humans; Hypoglycemia; Infant, Newborn; Israel; Male; Meconium; Meconium Aspiration Syndrome; Retrospective Studies; Risk Factors; Term Birth; Tertiary Care Centers

To examine the effects of pentoxifylline (PTX) on regional pulmonary and systemic inflammation after meconium aspiration, we studied 26 anesthetized and ventilated adult rats for 3 hours. Seventeen rats were instilled with human meconium (1.5 mL/kg, 65 mg/mL) intratracheally. After instillation of meconium, PTX (20 mg/kg, i.a.; n = 9) or saline (n = 8) was given to the subjects. Nine rats that were ventilated and not instilled with meconium served as sham group. Meconium instillation resulted in increased bronchoalveolar lavage (BAL) fluid tumor necrosis factor-α (TNF-α; P = 0.004 and P = 0.002, respectively), protein (P = 0.005 and P = 0.001, respectively) levels, and arterial oxygenation index (OI) in PTX and saline groups. PTX treatment prevented the increase of BAL fluid TNF-α, protein concentrations, and OI in the meconium-instilled lungs but had no statistically significant effect. These results indicate that meconium aspiration induces severe inflammation in the lung. PTX treatment affects the TNF-α production in the lungs and it may attenuate meconium-induced derangements.

Topics: Animals; Arteries; Bronchoalveolar Lavage Fluid; Disease Models, Animal; Humans; Infant, Newborn; Lung; Meconium; Meconium Aspiration Syndrome; Pentoxifylline; Pneumonia; Rats; Rats, Wistar; Tumor Necrosis Factor-alpha

To estimate the rates of meconium-stained amniotic fluid (AF) and adverse outcome in relation to gestational age and racial group, and to investigate the predictors of meconium-stained AF.. We studied 499,096 singleton births weighing at least 500 g, at 24 or more weeks of gestation, from 1988 to 2000. The predictors of meconium-stained AF from 37 weeks of gestation onward were determined using multiple logistic regression.. The crude meconium-stained AF rates in preterm, term, and postterm births were 5.1% (95% confidence interval [CI] 4.9-5.4), 16.5% (95% CI 16.4-16.6), and 27.1% (95% CI 26.5-27.6), respectively; the rates in blacks, South Asians, and whites were 22.6% (95% CI 22.2-23.1), 16.8% (95% CI 16.5-17.1), and 15.7% (95% CI 15.6-15.8), respectively. Independent predictors of meconium-stained AF included being black (odds ratio [OR] 8.4, 95% CI 2.4-28.8), vaginal breech delivery (OR 4.7, 95% CI 4.2-5.3), being South Asian (OR 3.3, 95% CI 1.3-8.3), and being in an advancing week of gestation (OR 1.39, 95% CI 1.38-1.40). More blacks (17.9%, 95% CI 17.3-18.4) and South Asians (11.8%, 95% CI 11.5-12.1) with good outcome and no risk factors for fetal hypoxia had meconium-stained AF than did whites (11.2%, 95% CI 11.1-11.4). Using white neonates born at 40 weeks as reference, the absolute risk of adverse outcome at 41 and 42 weeks were 2% and 5% in whites, 3% and 7%, in South Asians, and 7% and 11% in blacks.. Meconium-stained AF rates are different among races and across gestational age, and overall risk of adverse outcomes in meconium stained AF is low.. II.

Topics: Amniotic Fluid; Cohort Studies; Ethnicity; Female; Fetal Distress; Gestational Age; Humans; Infant, Newborn; Infant, Premature; Logistic Models; Meconium; Meconium Aspiration Syndrome; Predictive Value of Tests; Pregnancy; Pregnancy Complications; Pregnancy Outcome; Prenatal Care; Retrospective Studies; Risk Assessment

Most infants born through meconium-stained amniotic fluid (MSAF) are observed clinically for 24 h postnatally. Only 5% of infants born through MSAF develop the meconium aspiration syndrome (MAS), a serious condition requiring medical intervention.. To evaluate the value of 24-h postnatal observation of infants born through MSAF.. A cohort of 394 term neonates born through MSAF was studied. Data were collected on Apgar scores, the development of MAS and other perinatal factors.. Nineteen of the 394 (4.8%) infants born through MSAF developed MAS. 298 (76%) infants had a 5-minute Apgar score (5'AS) of >or=9. In this group the number of infants developing MAS (1; 0.3%) was significantly lower compared with the 5'AS

Topics: Amniotic Fluid; Apgar Score; Cohort Studies; Female; Humans; Infant, Newborn; Male; Meconium; Meconium Aspiration Syndrome; Netherlands; Patient Discharge; Perinatal Care; Pregnancy

Severe meconium aspiration syndrome is difficult to manage and has a high mortality in developing countries. Guidelines are available for the initial management. If the infant has been born through particulate meconium and is not vigorous, an inspection of the vocal cords by laryngoscopy is recommended. If meconium is seen at the cords it should, ideally, be sucked out of the trachea using an endotracheal tube as a suction device. However, as this needs a way of applying suction directly to the endotracheal tube it can be problematic. Commercially available equipment does exist, but in a resource-scarce setting, its cost could be prohibitive. We have adapted cheap suction connectors which can be adapted for this purpose.

Topics: Humans; Infant, Newborn; Intubation, Intratracheal; Laryngoscopy; Meconium; Meconium Aspiration Syndrome; Suction

Topics: Amniotic Fluid; Apgar Score; Female; Humans; Infant, Newborn; Meconium; Meconium Aspiration Syndrome; Patient Discharge; Perinatal Care; Practice Guidelines as Topic; Pregnancy

We hypothesized that fetal pancreatic digestive enzymes play a role in the lung damage after meconium aspiration. We studied the effect of meconium on the A549 alveolar epithelial cell line. The exposure of the cells to 0.5 to 5% meconium resulted in significant disruption of connections between A549 cells and caused dose-dependent cell detachment, without signs of cell death. A protease inhibitor cocktail prevented the A549 cell detachment induced by meconium. After the exposure to 2.5% meconium, a protective effect was quantified by measuring light absorbance by gentian violet stain of still attached cells. The protease inhibitor cocktail and chymostatin showed significant protective effects, increasing the number of attached cells by 135 and 123%, respectively (p < 0.05). Other individual protease inhibitors tested in the detachment assay (AEBSF, leupeptin, E-64, aprotinin, benzamidine, phosphamidon, and aminohexanoic acid) did not offer statistically significant protection. These results afford a new perspective on the pathophysiology of meconium aspiration syndrome (MAS). We speculate that disruption of intercellular connections and cell detachment from the basement membrane are key events in the pathology associated with MAS. The observed protective effects of protease inhibitors suggest that they may be useful in the treatment and/or prophylaxis of MAS.

Topics: Analysis of Variance; Cell Adhesion; Cell Line; Epithelial Cells; Gentian Violet; Humans; In Vitro Techniques; Infant, Newborn; Meconium; Meconium Aspiration Syndrome; Microscopy, Phase-Contrast; Oligopeptides; Peptide Hydrolases; Protease Inhibitors

Alveolar epithelial cells of neonates are directly exposed to aspirated meconium during meconium aspiration syndrome (MAS). This study was designed to investigate the influence of quantity and time of meconium exposure on the cell viability and caspase activity in type II human alveolar epithelial cells. Human alveolar epithelial cells were incubated with human meconium suspension at different concentrations and for different times. Cell viability and DNA fragmentation were investigated together with caspases activity and the amount of Bcl-2 protein present. We found that cell viability was significantly lower in cells exposed to a higher concentration of meconium. This was also true for cells exposed to meconium for longer. Significantly higher DNA fragmentation, an approximately two- to fivefold increase, was observed in cells that had been exposed to higher (5% and 10%) concentration of meconium compared to those treated with lower (0.1% and 1%) concentrations (P < 0.05). The activity of most apoptotic initiators (caspase 2, 8, 9, 10) and effectors (caspase 3, 6) were found to be significantly higher in cells subject to greater meconium exposure compared to cells with no or minor meconium exposure. The level of Bcl-2 was also found to be significantly decreased in meconium-exposed cells (P < 0.05). In conclusion, human meconium would seem to induce direct cell death as well as caspase-dependent apoptosis in alveolar epithelial cells; the amount and period of exposure to meconium are crucial factors in this process. Thus, removing aspirated meconium should alleviate lung cell damage in neonates and improve the outcome with MAS.

Topics: Apoptosis; Biological Products; Caspases; Cell Line; Cell Survival; DNA Fragmentation; Humans; Infant, Newborn; Meconium; Meconium Aspiration Syndrome; Proto-Oncogene Proteins c-bcl-2; Pulmonary Alveoli; Pulmonary Surfactants

To evaluate the impact of suction technique on the rate of meconium removal, oxygenation, and hemodynamics in an animal experimental model of meconium aspiration syndrome (MAS).. MAS was induced in ventilated rabbits using 3.5 ml/kg of 20% human meconium. Tracheal suction with either catheter suction (CS) or meconium aspirator (MA) was performed after meconium instillation. Percentage of meconium collection rate, PaO(2) trends for 2h after tracheal suction, and acute-phase SpO(2) trends were compared between CS and the other three groups, the tube was withdrawn while meconium was aspirated with an MA, then the trachea was reintubated 5, 10 or 15s after suctioning of meconium.. Percentage of meconium collection rate and PaO(2) showed no significant differences between groups. The MA group taking 15s for reintubation after meconium suctioning, showed a significantly lower acute-phase SpO(2) than the CS group (P<0.05). The time for SpO(2) to return to >or=90% was also longer in the MA group taking 15s for reintubation than in the CS group (P<0.05).. Intratracheal CS removed the same volume of meconium with less impact on desaturation compared with meconium aspiration in an animal model of MAS. Intratracheal CS may be benefit to remove meconium in non-vigorous infants with meconium-stained amniotic fluid at birth.

Topics: Animals; Blood Pressure; Catheterization; Catheters; Disease Models, Animal; Heart Rate; Humans; Infant, Newborn; Intubation, Intratracheal; Meconium; Meconium Aspiration Syndrome; Rabbits; Respiratory Function Tests; Respiratory Therapy; Suction; Trachea

We report a case of emergent massive meconium peritonitis due to intrauterine volvulus without malrotation. Fetal ascites was detected on a regular ultrasonographic examination, and fetal distress was found on cardiotocographic monitoring. The mother had noticed a slight decrease in fetal movements over the preceding 24 hours. Prenatal magnetic resonance imaging allowed us to distinguish the meconium from fetal peritoneal fluid and to evaluate the degree of compression of the fetal thoracic cavity. The infant was delivered by emergency cesarean section and demonstrated tense abdominal ascites with edema at birth. She required cardiopulmonary resuscitation and immediate paracentesis.

Topics: Adult; Cardiopulmonary Resuscitation; Cesarean Section; Female; Humans; Infant, Newborn; Meconium; Meconium Aspiration Syndrome; Peritonitis; Treatment Outcome; Ultrasonography, Prenatal

We previously showed that meconium causes lung cell death by apoptosis and inflammatory cytokine expression. Whether this is due to meconium exposure itself, or meconium related hypoxia remains unclear.. To elucidate the effects of meconium, saline, milk, hypoxia and hyperoxia induced lung injury.. We studied 5 groups of rabbit pups: (I) normal saline; (II) Milk; (III) 10% solution of meconium; (IV) only to 15 minutes of hypoxia (10% O(2)), and (V) 5 minutes of hypoxia (95% O(2)). After exposure lung lavage cells were used for apoptotic cell count and cytokine expression. In vitro response of human A 549 epithelial cells to meconium-and milk exposure was also studied.. There was no difference in cell death between saline and milk groups. However, meconium caused a significant cell loss compared to saline and milk-Inflammatory cytokines increased significantly in meconium group compared to saline or milk group. Although hypoxic and hyperoxic lungs showed increased inflammatory reaction compared to saline-treated lungs, this injury was not significant compared to meconium group. Studies with A549 cells also showed similar results.. We conclude that lung cell injury in meconium aspiration is mainly from meconium itself.

Topics: Animals; Animals, Newborn; Cell Line; Humans; Hypoxia; Infant, Newborn; Inflammation; Lung Injury; Meconium; Meconium Aspiration Syndrome; Milk; Rabbits

To determine the effect of clear liquor and meconium stained liquor on mode of delivery, and to evaluate neonatal outcome.. It was a Cross sectional analytical study, conducted in the department of Obstetrics and Gynaecology, Shaikh Zyed Federal Postgraduate Medical Institute/Hospital, Lahore and Shaikh Zaid Women Hospital Larkana, from April 2006 to March 2007. Two hundred and fifty patients from Larkana and 250 patients from Lahore in clear liquor group were included in the study. Similarly 125 patients from each city, that is 250 patients which had meconium stained liquor were included in group 2. The subjects with meconium stained amniotic fluid and clear amniotic fluid were registered as group 1 and 2. The socio demographic information, fertility history and gestational age of subjects were recorded. The investigations and information regarding mode of delivery and duration of labour were also noted. All babies delivered were attended by paediatricians.. In this study 500 cases with clear liquor and 250 cases of meconium stained liquor were selected from two cities, Lahore and Larkana. Out of these 55 (22%) patients had grade I meconium stained liquor, 140 (56%) patients and 55 (22%) patients had grade II and grade III meconium stained liquor respectively. The mode of delivery is significantly affected by meconium staining of liquor. The effect of meconium stained liquor was significant on time of delivery. There were 40 (16%) post date deliveries in meconium stained liquor as compared to 1% in subjects with clear liquor. The effect of meconium staining of liquor was significant on Apgar score, neonatal admission, meconium aspiration syndrome and neonatal deaths.. Meconium stained amniotic fluid (MSAF), is associated with increased neonatal morbidity and mortality. Caesarean sections were performed twice as frequently in women presenting with MSAF.

Topics: Amniotic Fluid; Apgar Score; Cross-Sectional Studies; Delivery, Obstetric; Female; Humans; Infant, Newborn; Meconium; Meconium Aspiration Syndrome; Pakistan; Pregnancy; Pregnancy Complications; Pregnancy Outcome; Prospective Studies

Meconium aspiration syndrome has a complex pathophysiology. Meconium activates the complement system and meconium-induced cytokine formation is differentially mediated by complement and CD14. C1-inhibitor (C1-INH) regulates complement and contact-system activation mainly by protease inhibition, but may reduce inflammation by other mechanisms as well.. The aim of the study was to investigate the initial mechanisms of meconium-induced complement activation and to study the effect of C1-INH on the meconium-induced inflammatory reaction.. Human serum from five donors was preincubated with an anti-MBL monoclonal antibody and then incubated with meconium for 30 min at 37 degrees C. Human cord whole blood, anticoagulated with lepirudin, from six donors was preincubated with C1-INH and then incubated with meconium for 30 min and 4h at 37 degrees C. Complement activation products specific for the different pathways were measured by ELISAs: classical pathway C1rs/C1-INH complexes, classical and lectin pathway C4d, alternative pathway C3bBbP, and terminal pathway sC5b-9 complex (TCC). A Bio-Plex Array Reader was used to measure 27 inflammatory mediators.. The anti-MBL monoclonal antibody significantly reduced meconium-induced formation of C4d by 63% (p=0.0159) and TCC by 27% (p=0.0079). C1-INH dose-dependently inhibited meconium-induced formation of C1rs/C1-INH complexes, C4d, C3bBbP, and TCC compared to albumin (p<0.002 for all). C1-INH induced a dose-dependent and substantial inhibition of meconium-induced formation of the proinflammatory cytokines TNFalpha, IL-1 beta, IL-6 and IFN-gamma (p<0.01 for all), the chemokines IL-8, MCP-1, MIP-1 alpha, MIP-1 beta, and eotaxin (p<0.02 for all), the growth factors G-CSF, GM-CSF, basic FGF, and PDGFbb (p<0.05 for all), and the anti-inflammatory cytokine IL-1ra (p<0.001).. Meconium activated the lectin complement pathway as well as the alternative pathway. C1-INH efficiently reduced a broad spectrum of inflammatory mediators even at the lowest concentration. Administration of C1-INH may thus reduce the inflammatory response in MAS.

Topics: Complement Activation; Complement C1; Complement C1 Inhibitor Protein; Complement Pathway, Alternative; Cytokines; Fetal Blood; Humans; Infant, Newborn; Inflammation; Meconium; Meconium Aspiration Syndrome

To provide clinician direction that is based on the best evidence available on suctioning at the perineum for infants born with meconium stained amniotic fluid.. The Medline database was searched for articles published in English from 2000 to 2008 on the topic of management of meconium at birth.. The recommendation was made according to guidelines developed by the Canadian Task Force on Preventive Health Care.

Topics: Amniotic Fluid; Canada; Databases, Factual; Humans; Infant, Newborn; Meconium; Meconium Aspiration Syndrome; Practice Guidelines as Topic; Suction

The pathogenetic cascade of meconium aspiration syndrome (MAS) in newborn infants is complex and still incompletely studied. The variable clinical presentation of MAS is basically connected with variation of the amount and consistency of aspirated meconium and also its distribution within the affected lungs. The contributing role of other factors, like intrauterine fetal compromises, lung maturity at the time of insult as well as direct and indirect effects of meconium and its components on the lung alveolar and vascular integrity and development, remains to be studied in further detail. Better understanding of the lung injury processes in MAS, specifically inflammatory injury and non-inflammatory apoptosis and their interplay, may offer new possibilities to treat the severely affected infants, and needs therefore to be explored. Systemic dispersion of intrapulmonary meconium and its components may further induce inflammatory circulatory changes and injurious effects in distant organs, but the mechanisms and clinical significance of these systemic complications are still poorly known. It is thus evident that lung injury processes and potent long-term consequences in various extrapulmonary organs, specifically the brain, as well as development of new approaches to their treatment and prevention form great challenges for future research of MAS.

Topics: Humans; Infant, Newborn; Inflammation; Lung; Meconium; Meconium Aspiration Syndrome

Topics: Amniotic Fluid; Child Development; Delivery, Obstetric; Humans; Infant, Newborn; Meconium; Meconium Aspiration Syndrome

One in every 7 pregnancies ends with meconium-stained amniotic fluid and approximately 5% of these infants develop the meconium aspiration syndrome (MAS). MAS is a severe disease of the (mainly) term neonate, characterized by respiratory distress, pulmonary inflammation, persistent pulmonary hypertension and chronic hypoxia. The pathophysiology of MAS is multifactorial and complex. In this article, we discuss the mechanical and chemical effects of meconium on a newborn's airway, meconium-induced inflammation, mediated by proinflammatory cytokines and chemokines, the complement system and the proinflammatory enzyme phospholipase A2. Furthermore, we focus on MAS-related apoptotic cell death, causing severe acute lung injury due to damage and detachment of lung airway and alveolar cells. Finally, risk factors for MAS development to identify those newborns that develop MAS and those who do not are discussed.

Topics: Apoptosis; Chemokines; Cytokines; Humans; Infant, Newborn; Lung; Meconium; Meconium Aspiration Syndrome; Phospholipases A2; Risk Factors

The role of meconium in the respiratory system was studied in newborns, who died from various causes (250 up to 3000 g of weight). We monitored tracheal rings response to dopamine, serotonin and ethanol in different concentrations (dopamine: 0,05 mg/ml, 0,5 mg/ml, 5 mg/ml; serotonin (5-HT): 10-4, 10-3, 10-2, 10-1 mol/dm3; ethanol: 0,02 ml, 0,5 ml, 1,0 ml; 96%). Tracheal smooth musculature tonus (TSM) was examined in 48 tracheal preparations taken after the newborn exitus due to different reasons. Based on functional researche of isolated preparations of tracheas, it may be concluded that: aspiration of meconium has not changed the response of TSM to dopamine, serotonin and ethanol (p>0,1) in comparison with the control group, which have died due to different lung inflammatory processes (e.g. pneumonia, bronchopneumonia, atelectasis, cerebral hemorrhage). The results suggest that meconium does not potentiate the constricting action of dopamine, serotonin and ethanol in tracheobronchial system. Meconium causes mild relaxation of the TSM through a mechanism that is not intermediated by the products of cyclooxygenases (prostaglandins, prostacyclins) from the tracheal epithelium or proteins. Also, as it seems, the direct activity of many tested acids in the smooth musculature has no significant impact on increase of the airways tonus in MAS syndrome.

Topics: Dopamine; Dose-Response Relationship, Drug; Ethanol; Humans; Infant, Newborn; Meconium; Meconium Aspiration Syndrome; Muscle, Smooth; Serotonin; Trachea

Topics: Humans; Infant, Newborn; Inflammation; Lung; Meconium; Meconium Aspiration Syndrome

The incidence of meconium aspiration syndrome (MAS), associated perinatal factors, morbidity and deaths varies widely. This study aimed to assess the perinatal attributes and morbidity associated with MAS.. Over a 2-year period, all neonates born through meconium-stained amniotic fluid (MSAF) were observed for respiratory distress (RD). Birth details, chest radiograph (CXR) and clinical course were documented. Neonates with consistent CXR findings whose RD could not otherwise be explained were defined as MAS.. Of 409 neonates born through MSAF, meconium was thick in 196 (47.9%). Fifty-five (13.4%) had RD and 45 (11.3%) were consistent with MAS. Six (1.5%) neonates died. Mean (SD) birthweight and gestation of MAS infants were 2721.9 (510.2) g and 38.67 (1.09) weeks, respectively. About one-third were of low birthweight and 28 were born by caesarean section. On univariate analysis, caesarean delivery, meconium in the trachea and thick meconium were the significant perinatal factors for the development of MAS. On multiple regression analysis, thick meconium was the only independent factor for MAS (OR 7.08, 95% CI 3.08-16.27, p<0.001). An Apgar score of

Topics: Amniotic Fluid; Apgar Score; Birth Weight; Delivery, Obstetric; Female; Gestational Age; Humans; Infant, Newborn; Meconium; Meconium Aspiration Syndrome; Pregnancy; Prospective Studies; Respiration, Artificial; Risk Factors

Topics: Humans; Infant, Newborn; Inflammation; Lung; Meconium; Meconium Aspiration Syndrome

To review and summarize experimental data examining the effects of different fractions of meconium, and to test the effect of albumin on meconium aspiration both as prophylactic and rescue treatment. Newborn piglets 2 to 5 days of age were made hypoxic and then instilled meconium or fractions of meconium intratracheally. Meconium-added albumin and albumin instilled after meconium were also tested. Lung function and inflammatory cytokines were measured. Both the lipid- and water-soluble fractions induce inflammation in the lungs with elevation of inflammatory cytokines. When meconium was mixed with albumin, the inflammatory effects of meconium were significantly ameliorated. Rescue therapy with intratracheal albumin 5 min after the meconium aspiration syndrome was induced also improved lung function. These results indicate that at least part of the symptoms seen in the meconium aspiration syndrome could be prevented by blocking the active substances of meconium such as bile acids and free fatty acids.

Topics: Albumins; Animals; Humans; Infant, Newborn; Lung; Meconium; Meconium Aspiration Syndrome; Swine

Passage of fetal bowel movement (meconium) is common (in about one out of six births), and in some the staining of the amniotic fluid is a sign of fetal distress. Inhalation of meconium (aspiration syndrome, in upto one out of five to eight such births) just before or at birth may be preventable by a coordinated approach by well-trained and informed birth attendants. Respiratory failure secondary to meconium aspiration syndrome (MAS) remains a major cause of morbidity and mortality in the neonatal population. Infants with hypoxemic respiratory failure because of MAS, persistent pulmonary hypertension of the newborn and pneumonia/sepsis have an increased survival with extracorporeal membrane oxygenation (ECMO). Other treatment options earlier limited to inotropic support, continuous airway pressure (CPAP), conventional ventilatory management, respiratory alkalosis, paralysis and intravenous vasodilators have been replaced by synchronized intermittent mandatory ventilation (SIMV), high-frequency oscillatory ventilation (HFOV), surfactant and inhaled nitric oxide (iNO). HFOV has been advocated for use to improve lung inflation while potentially decreasing lung injury through volutrauma. Other reports describe the enhanced efficacy of HFOV when combined with iNO. Subsequent to studies reporting that surfactant deficiency or inactivation may contribute to neonatal respiratory failure, exogenous surfactant therapy has been implemented with apparent success. Recent studies have shown that iNO therapy in the neonate with hypoxemic respiratory failure can result in improved oxygenation and decreased need for ECMO. However, these innovative interventions are costly, require a sophisticated infrastructure and are not universally accessible. In this paper, a context of systems-approach for prenatal, natal and postnatal management of babies delivered through meconium stained amniotic fluid (MSAF) so that adverse outcomes are minimized and the least number of babies require innovative ventilatory support is described. Previously reported data from a single urban perinatal center (Philadelphia, PA, USA), over a 6-year period (1995-2000), demonstrated that 14.5% (3370/23175 of live births babies were delivered with MSAF. These data also showed that 4.6% of babies (155/3370) with MSAF sustained MAS. Overall, 26% of babies (40/155) with MAS needed ventilatory support (or 0.17% of all live births); of these, only 20% (8/40 or 0.035% of live births) needed innovative ventila

Topics: Amniotic Fluid; Fetal Distress; Humans; Infant Mortality; Infant, Newborn; Meconium; Meconium Aspiration Syndrome; Perinatal Care

Overdistension of the lungs is a cause of ventilator-induced lung injury. In meconium aspiration syndrome, irregular overdistension of the lungs often occurs.. We investigated whether surfactant replacement could restore the terminal airspaces in the lungs that had been distended after meconium aspiration.. Meconium aspiration was induced by injecting meconium (50 mg x kg(-1)) into the airways of adult rats anesthetized with pentobarbital and ventilated with pressure-preset mode. The animals were further ventilated with or without surfactant replacement (100 mg x kg(-1)), and the sizes of the terminal airspaces were determined after fixing the lungs at an airway pressure of 10 cm H2O on deflation.. Approximately 75 min after aspiration (early analysis point), alveolar ducts were widened and the mean ratio of the largest terminal airspace size class (> or =63,000 microm(2)) was 38.7% (n = 7), which was significantly higher than that of controls (6%, n = 7). Three hours after the early analysis point, the ratio increased to 50.2% (n = 7, p < 0.05), but surfactant replacement reversed the ratio to 18.8% (n = 7, p < 0.05).. In rats with meconium aspiration, surfactant replacement restored the distended terminal airspaces of the lungs and kept the spaces from irregular overdistension.

Topics: Animals; Disease Models, Animal; Humans; Infant, Newborn; Lung; Male; Meconium; Meconium Aspiration Syndrome; Pulmonary Surfactants; Rats; Rats, Wistar; Tidal Volume

The pulmonary renin-angiotensin system (RAS) contributes to inflammation and epithelial apoptosis in meconium aspiration. It is unclear if both angiotensin II receptors (ATR) contribute, where they are expressed and if meconium modifies subtype expression. We examined ATR subtypes in 2 wk rabbit pup lungs before and after meconium exposure and with and without captopril pretreatment or type 1 receptor (AT1R) inhibition with losartan, determining expression and cellular localization with immunoblots, RT-PCR and immunohistochemistry, respectively. Responses of cultured rat alveolar type II pneumocytes were also examined. Type 2 ATR were undetected in newborn lung before and after meconium instillation. AT1R were expressed in pulmonary vascular and bronchial smooth muscle and alveolar and bronchial epithelium. Meconium increased total lung AT1R protein approximately 3-fold (p = 0.006), mRNA 29% (p = 0.006) and immunostaining in bronchial and alveolar epithelium and smooth muscle, which were unaffected by captopril and losartan. Meconium also increased AT1R expression >3-fold in cultured type II pneumocytes and caused concentration-dependent cell death inhibited by losartan. Meconium increases AT1R expression in newborn rabbit lung and cultured type II pneumocytes and induces AT1R-mediated cell death. The pulmonary RAS contributes to the pathogenesis of meconium aspiration through increased receptor expression.

Topics: Angiotensin II Type 1 Receptor Blockers; Angiotensin-Converting Enzyme Inhibitors; Animals; Apoptosis; Captopril; Cell Death; Cells, Cultured; Disease Models, Animal; Humans; Immunohistochemistry; Infant, Newborn; Losartan; Male; Meconium; Meconium Aspiration Syndrome; Pulmonary Alveoli; Rabbits; Rats; Rats, Sprague-Dawley; Receptor, Angiotensin, Type 1; Receptor, Angiotensin, Type 2; Renin-Angiotensin System; RNA, Messenger; Up-Regulation

Meconium aspiration syndrome has a complex, poorly defined pathophysiology. Meconium is a potent activator of complement in vitro and in vivo; the latter is associated with a systemic inflammatory response. The complement system and Toll-like receptors are 2 important upstream components of the innate immune system that act partly independently in the inflammatory network. The aim of this study was to investigate the relative role of complement and CD14 in meconium-induced cytokine production.. Human adult (n = 6) and cord whole blood (n = 6) anticoagulated with lepirudin was collected and distributed into tubes that contained inhibitory antibodies (anti-CD14, anti-C2, anti-factor D, or combinations thereof). The tubes were preincubated for 5 minutes before addition of meconium or buffer and then incubated for 4 hours at 37 degrees C. Complement activation was measured by quantification of the terminal sC5b-9 complement complex by enzyme-linked immunosorbent assay. A panel of 27 inflammatory mediators (cytokines, chemokines, and growth factors) was measured by using multiplex technology.. Fourteen of the 27 mediators measured were induced by meconium both in cord and adult blood. In cord blood, 2 additional chemokines were induced and the inflammatory response was, in general, more potent. Blocking of complement or CD14 differentially reduced the formation of most mediators, anti-CD14 being more effective. Notably, the combined inhibition of complement and CD14 almost completely abolished meconium-induced formation of the cytokines and the chemokines and markedly reduced the formation of growth factors. The endogenous lipopolysaccharide content of meconium could not explain the CD14-mediated response.. Meconium-induced triggering of the cytokine network is differentially mediated by complement and CD14. A combined inhibition of these effector mechanisms may be an alternative approach to reduce the inflammatory reaction in meconium aspiration syndrome.

Topics: Adult; Complement Activation; Complement System Proteins; Cytokines; Female; Fetal Blood; Humans; Immunity, Innate; In Vitro Techniques; Infant, Newborn; Inflammation Mediators; Lipopolysaccharide Receptors; Male; Meconium; Meconium Aspiration Syndrome; Pregnancy; Probability; Sensitivity and Specificity; Statistics, Nonparametric

To study the effects of meconium-stained amniotic fluid on the cord blood IgE level in neonates.. A total of 404 neonates with meconium-stained amniotic fluid who were born by cesarean delivery between August 2003 and August 2005 (meconium-stained group) and 256 neonates with normal amniotic fluid delivered by cesarean (control group) were enrolled in this study. The meconium-stained group consisted of 80 cases of mild, 62 cases of moderate and 262 cases of severe meconium-stained amniotic fluid. The cord blood IgE level was measured using ELISA.. The cord blood IgE level in the meconium-stained group was statistically higher than that in the control group (t = 4.03, P < 0.01). There were significant differences between the mild and severe meconium-stained subgroups and the control group for the cord blood IgE level (F=4.28, P < 0.01). The cord blood IgE level in neonates with premature rupture of the membrane between the meconium-stained and the control groups was statistically different. Sexes, gestational age, birth weight and birth order were not associated with the IgE level of cord blood.. The cord blood IgE levels in neonates with meconium-stained amniotic fluid increase. Premature rupture of the membranes may be associated with an increase of cord blood IgE level.

Topics: Amniotic Fluid; Asthma; Fetal Blood; Humans; Immunoglobulin E; Infant, Newborn; Meconium; Meconium Aspiration Syndrome

In accordance with the new guidelines from the American Academy of Pediatrics and the American Heart Association, all infants with meconium-stained amniotic fluid should no longer routinely receive intrapartum suctioning. If meconium is present and the newborn is depressed, the clinician should intubate the trachea and suction meconium and other aspirated material from beneath the glottis.

Topics: Amnion; Amniotic Fluid; Female; Humans; Infant, Newborn; Intubation, Intratracheal; Meconium; Meconium Aspiration Syndrome; Postpartum Period; Pregnancy; Suction

Meconium aspiration syndrome (MAS) is a life-threatening respiratory disease in infants born through meconium stained amniotic fluid (MSAF). The purpose of this study was to determine risk factors for MAS in the newborns of mothers who had meconium stained amniotic fluid in labour. A retrospective study of all full-term pregnancies with MSAF from May 2003 to October 2004 was designed at a teaching hospital. Development of MAS was the primary outcome. Maternal details, mode of delivery and neonatal details (Apgar score, reassuring or non-reassuring fetal heart rate tracing and birth weight) were evaluated. During the study period, there were 2,603 deliveries of whom 302 (11.6%) had MSAF. MAS developed in 64 of these infants (21.1%). Compared with healthy neonates with MSAF, those with MAS had higher rate of non-reassuring fetal heart rate (FHR) tracing, thick meconium and Apgar score < or =5 at 5 min. The neonatal birth weight was lower in the MAS group, maternal age, parity, gestational age and mode of delivery were not significantly different in the two group. We found the severity of meconium, low Apgar score at 5 min and non-reassuring FHR tracing was associated with MAS in MSAF pregnancies.

Topics: Adult; Amniotic Fluid; Apgar Score; Female; Gestational Age; Heart Rate, Fetal; Humans; Infant, Newborn; Meconium; Meconium Aspiration Syndrome; Retrospective Studies; Risk Factors

Complications from meconium aspiration syndrome (MAS) remain significant despite a variety of therapeutic interventions. Clara cell protein (CC10) is a novel anti-inflammatory agent that can also inhibit phospholipase A2 (PLA2) (an important component of meconium). The present study examined whether administration of recombinant human CC10 (rhCC10) would reduce inflammation and improve lung function in a piglet model of MAS. Following meconium instillation, piglets exhibited significant physiologic dysfunction that improved significantly after surfactant administration. Analysis of tracheal aspirates revealed significant increases in both tumor necrosis factor (TNF) alpha and interleukin (IL)-8 after meconium instillation. rhCC10-treated animals had significantly lower TNF-alpha levels at 24 h (561 +/- 321 versus 1357 +/- 675 pg/mL, p < 0.05) compared with saline controls. There were no differences between rhCC10-treated and untreated groups with respect to other measured physiologic variables or inflammatory markers, including secretory PLA2 activity. Histologic analyses revealed marked inflammatory infiltrates and thickened alveolar walls, but no significant differences among rhCC10 and control animals. Newborn piglets with MAS have significant physiologic dysfunction, marked inflammatory changes and histologic abnormalities, which was partially counteracted by a single dose of exogenous surfactant and rhCC10.

Topics: Animals; Animals, Newborn; Anti-Inflammatory Agents; Bronchoalveolar Lavage Fluid; Disease Models, Animal; Drug Therapy, Combination; Enzyme Inhibitors; Humans; Infant, Newborn; Interleukin-8; Lung; Meconium; Meconium Aspiration Syndrome; Phospholipases A2, Secretory; Pulmonary Surfactants; Recombinant Proteins; Swine; Time Factors; Tumor Necrosis Factor-alpha; Uteroglobin

To better understand the mechanisms contributing to altered airway reactivity in the meconium aspiration syndrome, in this study we investigated whether there could be a meconium dose-dependent response of tracheal smooth muscle and lung tissue reactivity to histamine and acetylcholine in vitro. Tracheal and lung tissue strips from healthy guinea pigs were incubated for 1 hour in organ chambers with three different concentrations of meconium (1, 2, and 5 mg/ml) or in Krebs-Henseleit solution. Thereafter, the contractile responses to histamine and acetylcholine were recorded. Cumulative doses of histamine and acetylcholine increased reactivity of the strips in all groups. Tracheal smooth muscle reactivity to histamine and acetylcholine (10(-5)-10(-3) mol/l) was highest with the highest meconium concentration. In contrast, lung tissue reactivity tended to decrease with increasing meconium concentration. The mechanisms influencing the airway smooth muscle contractile response to meconium require further studies.

Topics: Acetylcholine; Airway Resistance; Animals; Bronchoconstrictor Agents; Dose-Response Relationship, Drug; Guinea Pigs; Histamine; Humans; In Vitro Techniques; Infant, Newborn; Lung; Meconium; Meconium Aspiration Syndrome; Trachea

Histological studies show that amniotic fluid cellular content (AFCC) causes in the middle ear a foreign body reaction, the extent and severity of which depends upon the massiveness of contamination. We studied how factors related to birth and environment affect proneness to acute otitis media (AOM) in infants born through meconium contaminated amniotic fluid.. From the birth records of infants born from 1996 to 2000 a list was made of those born through meconium contaminated amniotic fluid with pulmonary aspiration and tracheal suctioning, followed by treatment in a neonatal intensive care unit. Thirty-seven such children formed the study group, 43 children matching the study cases but born through clear fluids formed the control group. Birth and environmental factors together with the frequency and number of episodes of AOM were analyzed in all, based on a verified questionnaire. In addition, 27 children in the study group and 21 in the control group received a specialist ENT examination, hearing tests and tympanometry.. The events at delivery were highly significantly different between the two groups, manifested by the lower Apgar points in the study group (p<0.001) while other birth and environmental factors appeared equalized. The first episode of AOM in the study group came earlier than in the control group and their frequency was significantly higher during the 1st and 2nd year of life and during the entire observation period (p<0.001). Tympanostomy was performed more often in the study group. Tympanometry showed more cases of reduced static admittance and negative pressure than in the control group and hearing was poorer.. Cases with compromised delivery through meconium contaminated fluids, resulting in pulmonary aspiration and in need of intensive care treatment, form a risk group, which should be closely followed. Early nasopharyngeal suctioning of AFCC may reduce its entry into the middle ear. A prolonged episode of AOM suggests mucosal involvement of several middle ear compartments, shown by histological studies to occur in all cases of massive contamination. Placement of a ventilation tube after the first prolonged AOM allows regression of the granulation tissue in the air spaces together with the secretory elements in the mucosa.

Topics: Acoustic Impedance Tests; Amniotic Fluid; Ear, Middle; Humans; Infant; Infant, Newborn; Meconium; Meconium Aspiration Syndrome; Otitis Media; Respiratory Distress Syndrome, Newborn; Risk Factors

The effects of dexamethasone on in vitro airway reactivity associated with lung inflammation were investigated in rabbits with meconium aspiration. Oxygen-ventilated adult rabbits received an intratracheal bolus of 4 ml/kg body weight of saline (Sal, n = 4) or human meconium (25 mg/ml). Thirty minutes later, meconium-instilled animals intravenously received 0.5 mg/kg of dexamethasone (Dexa, n = 6), or were left without treatment (Meco, n = 5). The animals were ventilated for a further 5 hr and then sacrificed. The left lungs were lavaged with saline, and the white blood cell (WBC) count was estimated. Tracheal and right-lung tissue strips were placed into organ chambers with Krebs-Henseleit solution. Cumulative doses of histamine (10(-8)-10(-3) mol/l) and acetylcholine (10(-8)-10(-3) mol/l) were added to the chambers, and recordings of contractions were made after a 30-min loading phase with a tension of 4 grams, and another 30-min adaptation phase with a tension of 2 g. Tracheal smooth muscle in vitro reactivity to histamine was higher in the Meco than in the Sal group, and dexamethasone decreased the reactivity compared to the Meco group (P < 0.05). Lung tissue in vitro reactivity to histamine was slightly higher in the Meco than in the Sal group (P > 0.05), and dexamethasone decreased the reactivity compared to both the Meco and Sal groups (P < 0.05). No between-group differences were observed in tracheal or lung in vitro reactivity to acetylcholine (P > 0.05). In the Meco group, blood WBC (P > 0.05) and neutrophil (P < 0.05) counts were lower than in the Sal and Dexa groups. Lung neutrophils and eosinophils were higher in both the Meco and Dexa groups than in the Sal group (P < 0.01). Dexamethasone decreased neutrophils (P < 0.05) compared to the Meco group. Meconium-induced airway hyperreactivity to histamine and lung inflammation were alleviated by dexamethasone.

Topics: Animals; Anti-Inflammatory Agents; Dexamethasone; Disease Models, Animal; Humans; In Vitro Techniques; Infant, Newborn; Lung; Meconium; Meconium Aspiration Syndrome; Muscle, Smooth; Pneumonia; Rabbits; Trachea; Treatment Outcome

Meconium aspiration syndrome (MAS) remains a relevant cause of neonatal respiratory failure and is characterized by severe impairment of pulmonary gas exchange, surfactant inactivation, and pronounced inflammatory changes. Surfactant administration has been shown as an effective treatment strategy in MAS. The present study aimed at investigating the impact of a recombinant surfactant protein (SP)-C-based surfactant on pulmonary gas exchange and lung function in this model of neonatal lung injury. Furthermore, SP-B and -C were determined on the transcriptional and protein level.. Laboratory experiment.. University laboratory.. Twenty three newborn piglets (median age 6 days, weight 1900-2500 g).. Piglets were intubated and mechanically ventilated and then received 20% sterile meconium (5 mL/kg) for induction of lung injury. After 30 mins, animals were randomized for control (n = 7, MAS controls), recombinant SP-C surfactant (n = 8), or natural surfactant (n = 8). Surfactant preparations were administered as an intratracheal bolus (75 mg/kg), and animals were ventilated for another 330 mins. Nonventilated newborn piglets at term (n = 28; median weight 1484 g, range 720-1990 g) served as a healthy reference group (healthy controls).. Lung function variables, arterial blood gas samples, and lung tissues were obtained. Expression of SP-B and -C messenger RNA was quantified in left lung lobe tissue using real-time polymerase chain reaction. Protein concentrations were determined by enzyme-linked immunosorbent assay. Scanning electron microscopy and transmission electron microscopy were performed in tissue samples of the right lung lobe. Compared with healthy controls, SP-B messenger RNA expression was significantly increased in MAS (p < .02), whereas SP-C messenger RNA expression was found to be significantly reduced (p < .001). SP concentrations, however, were not significantly different. Although a significant improvement of gas exchange and lung function was observed after surfactant administration in both groups, surfactant messenger RNA expression and protein concentrations were not significantly altered. Scanning and transmission electron microscopy showed severe pulmonary ultrastructural changes after meconium aspiration improving after surfactant treatment.. Impairment of lung function in MAS, associated with marked changes in SP messenger RNA expression, can be sufficiently treated using recombinant SP-C-based or natural surfactant. Despite improved lung function and gas exchange as well as pulmonary ultrastructure after treatment, pulmonary SP messenger RNA expression and concentrations remained significantly affected, giving important insight into the time course following surfactant treatment in MAS.

Topics: Animals; Animals, Newborn; Base Sequence; Blood Gas Analysis; Disease Models, Animal; Female; Humans; Infant, Newborn; Meconium; Meconium Aspiration Syndrome; Molecular Sequence Data; Pulmonary Gas Exchange; Pulmonary Surfactant-Associated Protein C; Pulmonary Surfactants; Random Allocation; Recombinant Proteins; Reference Values; Respiratory Function Tests; Respiratory Insufficiency; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; Sensitivity and Specificity; Swine

Topics: Animals; Animals, Newborn; Disease Models, Animal; Humans; Infant, Newborn; Meconium; Meconium Aspiration Syndrome; Pulmonary Surfactant-Associated Protein C; Pulmonary Surfactants; Random Allocation; Respiratory Function Tests; Respiratory Insufficiency; Sensitivity and Specificity; Swine

Lung surfactants (LSs) form a monolayer at the lung's alveoli air-solution interface and play a crucial role in making normal breathing possible by reducing the surface tension. LS are affected by various agents that hamper their normal functioning. Tobacco smoke [Bringezu, F.; Pinkerton, K. E.; Zasadzinski, J. A. Langmuir 2003, 19, 2900-2907] and meconium, the first excrement of the newborn, are examples for such LS poison. In neonates, intrauterine aspiration of meconium is a known cause for morbidity and mortality. We studied in vitro the interactions between modified porcine LSs (Curosurf), used as LS replacement, and meconium, as well as between their artificial analogues, phospholipids mixture, and taurocholic acid (TA), respectively. The interactions were examined both in the bulk solution and at the air-water interface, representing the pre- and postnatal situations. It was found that the artificial analogues represent the natural system reliably and exhibit similar effects. TA, a principle component of bile, is an amphiphilic sterol compound in which the hydrophilic and hydrophobic moieties are presented at different faces of the sterol plane. Here we found that TA affects the structure of both monolayers at the interface and surfactant aggregates in solution. A likely poisoning mechanism is by stereoselective penetration of TA into the lamellar or monolayer structures, thus disrupting the contiguous structure of the intact monolayer or the bilayer vesicle structure.

Topics: Animals; Biological Products; Humans; Infant, Newborn; Lipid Bilayers; Meconium; Meconium Aspiration Syndrome; Phase Transition; Phospholipids; Pulmonary Surfactants; Swine; Taurocholic Acid

Meconium aspiration syndrome (MAS) is a serious neonatal disease with multifactor pathogenesis and long-term sequelae on the developing respiratory system. Since the altered airway reactivity may play a role in MAS, this study investigated whether 1 hour-lasting in vitro incubation of rabbit tracheal and lung tissue strips with meconium would also increase the airway reactivity.. Trachea and lungs of adult healthy rabbits were excised. Smooth muscle reactivity was estimated by an in vitro method using organ chambers. After the adaptation of tissue strips, 1 ml of suspended meconium (Meconium) was added into two chambers with one tracheal and one lung strip for another 1 hour. The two other chambers were incubated only with Krebs-Henseleit's buffer (Control). Cumulative doses of histamine (10(-8)-10(-3) mol/l) were added after finishing the incubation period and a continuous recording of contractions was made.. The contractile response of the lung tissue smooth muscle to histamine was recorded to decrease non-significantly in Meconium group when compared to Control group. The tracheal tissue reactivity to histamine at concentrations of 10(-8)- 10(-4) mol/l was lower in Meconium group than in Control group. Significant differences appeared only at concentrations of 10(-8), 10(-7), and 10(-6) mol/l (p=0.041, p=0.033, and p=0.019, respectively).. One-hour-lasting in vitro incubation of tracheal and lung tissue strips with meconium significantly decreased the tracheal reactivity to histamine and slightly, but non-significantly decreased the lung tissue reactivity to histamine (Fig. 1, Ref. 6).

Topics: Animals; Histamine; Humans; In Vitro Techniques; Infant, Newborn; Lung; Meconium; Meconium Aspiration Syndrome; Muscle Contraction; Muscle, Smooth; Rabbits; Trachea

Meconium staining of the skin is a common event associated with fetal hypoxia, stillbirths, weak-born piglets, and neonatal mortality. Aspiration of meconium leads to meconium aspiration syndrome (MAS). This study was undertaken to assess the relationship between the degree of meconium staining of the skin at birth, meconium aspiration, and pulmonary changes in porcine neonates. A total of 353 farrowing sows and 3,693 born piglets were monitored during parturition and for 15 days after delivery. Umbilical cords were classified as normal or ruptured. Meconium staining in the skin was graded as nonstained, mildly, moderately, and severely stained. Mortality from birth to 15 days of age was 8.4%. The lungs from 60 meconium-stained piglets and 60 lungs from nonstained piglets were collected and microscopically examined for meconium aspiration and inflammation. Rupture of the umbilical cord was significantly higher (P < 0.01) in meconium-stained piglets. Microscopically, 32% and 40% of the lungs had evidence of meconium for the stained and nonstained groups, respectively. The microscopic grade of meconium aspiration and inflammatory cells was not different between nonstained and meconium-stained piglets. Aspiration of meconium induced a granulomatous response in the lungs. It was concluded that the grade of meconium staining is a good indicator of fetal hypoxia, but not a good predictor for meconium aspiration and MAS in piglets.

Topics: Animals; Animals, Newborn; Fetal Death; Fetal Hypoxia; Humans; Infant, Newborn; Lung; Meconium; Meconium Aspiration Syndrome; Skin; Swine; Swine Diseases; Umbilical Cord

Evidence of meconium-stained amniotic fluid during labor suggests implementation of close monitoring of fetal well-being.. Our purpose was to compare fetal oxygen saturation between cases with normal and meconium stained amniotic fluid.. Fetal oxygen saturation was continuously recorded with use of Nellcor N-400 fetal pulse oximeter in 30 control cases of term labour of normal, and 30 cases of meconium stained amniotic fluid. Distribution of fetal oxygen saturation values during 5 periods of labour was analyzed and compared between the examined groups, and presented in forms of Tables, together with neonatal umbilical artery pH values, Apgar score, birth weight and percentage of caesarian sections performed.. No significant differences in fetal oxygen saturation, neonatal umbilical artery pH, birth weight and caesarian sections rate were observed between analyzed groups. Newborns 1-th minute Apgar score (mean value) and base excess was lower in meconium group compared to control group.. Our data demonstrate, that fetal oxygen saturation trends to decrease during labour in fetuses in both groups.

Topics: Amniotic Fluid; Case-Control Studies; Female; Fetal Blood; Fetal Monitoring; Humans; Infant, Newborn; Meconium; Meconium Aspiration Syndrome; Obstetric Labor Complications; Oximetry; Oxygen; Predictive Value of Tests; Pregnancy; Pregnancy Outcome

Meconium aspiration syndrome is a serious condition of the newborn characterized by pulmonary inflammation with substantial neutrophil infiltration. We recently showed that meconium is a potent activator of complement. The aim of the present study was to investigate a possible role for complement in meconium-induced neutrophil activation. Meconium was incubated in human whole blood anticoagulated with lepirudin, a specific thrombin inhibitor that does not affect complement activation. Complement activation was detected by measuring the terminal complement complex. Neutrophil oxidative burst and changes in CD11b and L-selectin expression were measured by flow cytometry. Complement was inhibited using the MAb 166-32 and 137-26, which block factor D and neutralize C5a, respectively. Meconium markedly activated the neutrophils, as revealed by up-regulation of CD11b, accentuation of L-selectin shedding, and induction of oxidative burst. Complement inhibition using the anti-factor D antibody completely (95-100%) blocked meconium-induced changes in CD11b and L-selectin expression, whereas oxidative burst was reduced by 60-70%. The anti-C5a antibody inhibited the neutrophil activation to the same extent as anti-factor D. The data suggest that complement activation is largely responsible for the neutrophil inflammatory responses induced by meconium in vitro and that C5a is a key mediator of this response.

Topics: Antibodies, Monoclonal; CD11b Antigen; Complement Activation; Complement C5a; Complement System Proteins; Dose-Response Relationship, Drug; Flow Cytometry; Hirudins; Humans; Infant, Newborn; Inflammation; L-Selectin; Meconium; Meconium Aspiration Syndrome; Neutrophil Activation; Neutrophils; Oxidative Stress; Protein Binding; Recombinant Proteins; Respiratory Burst; Syndrome

We have recently shown that albumin added to meconium before intratracheal instillation in newborn pigs limits detrimental effect on the lungs and reduces increase of IL-8. The aim of this study was to test the effect of albumin instillation as rescue treatment in meconium aspiration syndrome (MAS). MAS was induced in hypoxic piglets by lung instillation of meconium (MAS I = 675 mg/kg, n=12; MAS II=540 mg/kg, n=14). Morbidity and mortality differed (MAS I, dead=7/12; MAS II, dead=5/14). MAS groups were randomized to postmeconium instillation of either bovine albumin (30%, 1.4 mL/kg; MAS I, n=6; MAS II, n=7) or isotonic saline (9 mg/mL, 1.4 mL/kg; MAS I, n=6; MAS II, n=7). The controls (n=4) were tested by sequential instillation of saline (9 mg/mL, 5 mL/kg) and albumin (30%, 1.4 mL/kg). Lung function and gas exchange deteriorated significantly after instillation of meconium [oxygenation index (OI): MAS I, +814%; MAS II, +386%; ventilation index (VI): MAS I, +256%; MAS II, +162%; compliance: MAS I, -53%; MAS II, -44%]. Increases of tracheal IL-8 correlated to deterioration of lung function were 10- (MAS I) and 5-fold (MAS II) (p <0.001). Lung compliance was higher in albumin instillation versus saline instillation (MAS I, p=0.008; MAS II, p=0.002). Albumin did not influence intergroup differences in IL-8, hemodynamics, OI, or VI. MAS-induced IL-8 increases correlated with deterioration of lung function (OI, VI, and compliance). Rescue treatment with albumin in meconium aspiration improved lung compliance in piglets and may represent a new therapeutic approach to MAS.

Topics: Albumins; Animals; Animals, Newborn; Blood Chemical Analysis; Cattle; Hemodynamics; Humans; Infant, Newborn; Interleukin-8; Lung; Lung Injury; Meconium; Meconium Aspiration Syndrome; Statistics as Topic; Swine

The meconium aspiration syndrome is an important cause of respiratory distress in newborn infants. Alveolar macrophages (AMs) provide a first line of defense in the lower respiratory tract against inhaled pathogens and particles such as meconium. In this study, we examined the effect of meconium on two primary macrophage functions: phagocytosis and respiratory burst. Short-term exposure of rat NR8383 AMs to sterile meconium from human or equine neonates (1.2-24 mg/mL) produced a dose-dependent decrease in phagocytosis of fluorescent latex beads. This effect was not due to decreased cell viability or to an elevation of intracellular cAMP. The effect of short-term exposure to meconium on the respiratory burst response in AMs was quantified using flow cytometry to measure oxidation of dichlorofluorescin diacetate. A robust respiratory burst was triggered when AMs were exposed to 12 or 24 mg/mL meconium. This effect was attenuated but not eliminated by filtration of the meconium. However, subsequent to meconium exposure, AMs had a reduced respiratory burst in response to stimulation with phorbol myristate acetate. In addition, AMs that were exposed to meconium for an extended period (24 h) showed DNA fragmentation indicative of apoptosis. Meconium therefore may interfere with AM function by inducing oxidative stress and apoptosis. Tissue injury from release of reactive oxygen species by AMs may be important in the pathophysiology of the meconium aspiration syndrome.

Topics: Animals; Animals, Newborn; Apoptosis; Cell Line; Cyclic AMP; Horses; Humans; In Vitro Techniques; Infant, Newborn; Macrophages, Alveolar; Meconium; Meconium Aspiration Syndrome; Phagocytosis; Rats; Respiratory Burst

Hyaluronan (HA), an ionic polymer, is normally present in the alveolar subphase and is known to decrease lung surfactant inactivation caused by serum in vitro. In this study, we examined whether HA can ameliorate the inactivating effects of meconium in vitro and in vivo. Surface activities of various mixtures of Survanta, HA, and meconium were measured using a modified pulsating bubble surfactometer. With meconium, almost all surface activity measures were improved by the addition of HA of several molecular weights at a concentration of 0.25%. Anesthetized, paralyzed rats were maintained on positive-pressure ventilation. After lung injury by instillation of meconium, they were treated with Survanta, Survanta with HA, or control mixtures. Serial measures of blood gases and peak inspiratory pressure were recorded for the duration of the experiment. When the Survanta plus HA group was compared with the Survanta alone group, arterial oxygen tension averaged 117% higher, peak inspiratory pressure was 27% lower at the end of the experiment, and lung compliance also showed significant improvement. These results indicate that HA added to Survanta decreases inactivation caused by meconium in vitro and improves gas exchange and pulmonary mechanics of animals with meconium-induced acute lung injury.

Topics: Animals; Arteries; Biological Products; Disease Models, Animal; Humans; Hyaluronic Acid; In Vitro Techniques; Infant, Newborn; Ions; Lung; Lung Injury; Male; Meconium; Meconium Aspiration Syndrome; Oxygen; Phospholipids; Polymers; Rats; Rats, Sprague-Dawley; Surface-Active Agents; Time Factors

To study the impact of neonatal resuscitation program (NRP) guidelines on delivery room (DR) management of infants born through meconium-stained amniotic fluid (MSAF).. A retrospective study of all term (>or=37 weeks) infants born through MSAF was performed. Patients were divided into two periods: pre year 2000 NRP and post year 2000 NRP. Meconium consistency, APGAR scores and intubation (INT) for suctioning and respiratory outcome were recorded. Groups were analyzed using chi (2) tests and stepwise logistic regression.. The incidence of MSAF remained constant in period 1 (13.6%) and period 2 (13.1%) while the proportion of infants intubated fell from 67 to 41% (p<0.001). The incidence of meconium aspiration and nonspecific respiratory distress did not differ between groups.. Since the implementation of year 2000 NRP guidelines, the rate of DR INT for tracheal suctioning has fallen significantly without a change in overall respiratory complications. Results of this study support the efficacy of year 2000 NRP recommendations.

Topics: Amniotic Fluid; Delivery Rooms; Female; Guideline Adherence; Humans; Infant, Newborn; Intubation, Intratracheal; Meconium; Meconium Aspiration Syndrome; Obstetrics; Practice Guidelines as Topic; Practice Patterns, Physicians'; Pregnancy; Resuscitation; Retrospective Studies; Suction; Treatment Outcome

Meconium aspiration syndrome (MAS) is a clinical condition in the newborn infant with a significant morbidity and mortality. The complex pathophysiology of MAS, leading to both pulmonary and systemic complications, is characterized by an incompletely understood inflammatory reaction. Treatment is symptomatic, mainly limited to airway cleaning and ventilatory support. In this study, we show for the first time that meconium is a potent activator of complement, a key mediator of inflammation. In vitro, meconium activated the alternative complement pathway in human umbilical cord serum as judged by a substantial increase in the alternative pathway convertase C3bBbP. The activation proceeded through C3 (C3bc) and the terminal C5-9 pathway (terminal SC5b-9 complement complex), whereas the classical and lectin pathways were not activated (C1rs-C1-inhibitor complexes and C4bc). The lipid fraction, containing, e.g. free fatty acids, and the water fraction, containing, e.g. bile acids, contributed equally to the complement activation. A blocking antibody to factor D (alternative pathway) completely inhibited the meconium-induced complement activation, whereas blocking antibodies to mannose-binding lectin (lectin pathway) and C2 (classical and lectin pathway) had no effect. In vivo, meconium induced systemic complement activation in a piglet model of MAS, paralleling the increase in lung dysfunction. In conclusion, meconium is a potent activator of the complement system both in vitro and in vivo. Complement may be important in the pathogenesis of MAS, and specific complement inhibition might be a possible treatment approach in MAS.

Topics: Age Factors; Animals; Anticoagulants; Complement Activation; Complement C1; Dextran Sulfate; Female; Fetal Blood; Humans; Infant, Newborn; Lipopolysaccharides; Meconium; Meconium Aspiration Syndrome; Pregnancy; Serum; Serum Albumin; Swine

Topics: Amniotic Fluid; Humans; Infant, Newborn; Intubation, Intratracheal; Meconium; Meconium Aspiration Syndrome; Practice Guidelines as Topic; Resuscitation; Suction

Topics: Amniotic Fluid; Bradycardia; Humans; Infant, Newborn; Intubation, Intratracheal; Meconium; Meconium Aspiration Syndrome; Positive-Pressure Respiration; Practice Guidelines as Topic; Resuscitation; Suction

Meconium aspiration induces pulmonary inflammation and reduces surfactant function. We hypothesized that albumin mixed with meconium attenuates pulmonary inflammation and improves surfactant function after meconium aspiration. We measured the concentration of free fatty acids (FFA) in the meconium (110 mg dry weight/mL) and added albumin to provide a molar FFA:albumin ratio of 1:1. Newborn piglets, 0-2 day of age, artificially ventilated and exposed to hypoxemia by ventilation with 8% O2, were randomized to group A receiving meconium (n = 12), or group B receiving meconium + albumin (n = 12), 3 ml/kg intratracheally. The animals were reoxygenated for 8 h. Reoxygenation was started when mean arterial blood pressure was < 20 mm Hg or base excess was < -20 mmol/L. During 8 h of reoxygenation the interleukin-8 concentrations in tracheobronchial aspirates increased 5-fold more in the meconium vs. the meconium + albumin groups (93 +/- 56 vs. 18 +/- 4 pg/mL, p < 0.005). There were no differences between the groups for tumor necrosis factor alpha in tracheobronchial aspirates, recruitment of inflammatory cells in the airspaces or surfactant function in bronchoalveolar lavage fluid. In conclusion, albumin significantly decreased interleukin-8 concentrations in tracheobronchial aspirates after meconium aspiration.

Topics: Animals; Animals, Newborn; Bronchi; Bronchoalveolar Lavage Fluid; Fatty Acids, Nonesterified; Humans; Hypoxia; Infant, Newborn; Interleukin-8; Lung; Meconium; Meconium Aspiration Syndrome; Oxygen; Pulmonary Surfactants; Serum Albumin, Bovine; Surface Tension; Swine; Trachea; Tumor Necrosis Factor-alpha

Topics: Biological Products; Fluorocarbons; Humans; Hydrocarbons, Brominated; Infant, Newborn; Meconium; Meconium Aspiration Syndrome; Pulmonary Surfactants; Surface Tension; Syndrome

The high false-positive rate of electronic fetal heart rate monitoring is the major obstacle to the correct prediction and diagnosis of intrapartum fetal distress. Fetal pulse oximetry is a safe and accurate indicator of fetal oxygenation. The aim of this study was to evaluate the clinical use of this technique for the diagnosis of fetal hypoxia and for prevention of fetal metabolic acidosis and asphyxia during labour, in the presence of meconium-stained amniotic fluid with or without abnormal fetal heart rate patterns, using a threshold value of 30% oxygen saturation.. Fetal blood oxygen saturation levels (SpO2) of 58 term fetuses with non-reassuring fetal status were measured during labour by fetal pulse oximetry. In 35 cases the amniotic fluid was stained with meconium at onset of labour. Mean SpO2 levels at the different stages of labour were matched against fetal heart rate patterns, the amniotic fluid status, and neonatal outcome. The 35 cases with meconium-stained amniotic fluid were compared with a control group of 28 pregnant women at term who had meconium-stained amniotic fluid during labour but were not monitored by pulse oximetry.. When the fetal heart rate tracings were abnormal, mean SpO2values were significantly lower in the first 30 minutes of application and in the last 30 minutes of labour or before Cesarean section. Meconium-stained amniotic fluid was associated with lower SpO2values only when fetal heart monitoring showed a "non-reassuring" pattern. No cases were observed with severe neonatal acidosis, with Apgar score <7 at 5 minutes, or with other adverse neonatal events. In patients with meconium-stained amniotic fluid, neonatal outcomes were better in the group monitored by pulse oximetry versus the control group, although the differences were not statistically significant.. Continued monitoring of fetal oxygen saturation combined with fetal heart rate monitoring may improve accuracy in the evaluation of fetal well-being. As a result, labour could be more safely managed in pregnancies with non-reassuring fetal status as measured by conventional methods, especially in the presence of meconium-stained amniotic fluid.

Topics: Adult; Amniotic Fluid; Female; Fetal Monitoring; Humans; Infant, Newborn; Labor, Obstetric; Meconium; Meconium Aspiration Syndrome; Oximetry; Oxygen; Pregnancy; Pregnancy Complications

Neonatal meconium aspiration often produces severe respiratory distress due to an inflammatory pulmonary injury, but the extension of this damaging reaction to the noncontaminated lung regions is still uncertain. To investigate the presence of generalized pulmonary inflammatory response, 31 anesthetized and ventilated neonatal piglets (1-3 d) were studied. Meconium (n = 16) or saline (n = 15) was instilled unilaterally into the right lung, and analysis of the lung tissue or bronchoalveolar lavage (BAL) fluid from both lungs was performed after 12 h. Meconium increased the wet/dry weight ratio, histologic tissue injury score and tissue myeloperoxidase activity as well as BAL fluid total cell count in the contaminated lung. Tumor necrosis factor-alfa concentrations in BAL fluid did not however differ significantly. Furthermore, in the meconium-instilled lungs the tissue and lavage fluid catalytic activity of phospholipase A2 (PLA2) and tissue PLA2 group-I and group-II concentrations were significantly elevated. Although BAL fluid catalytic activity of PLA2 was moderately increased also in the meconium noninstilled lung, significant inflammatory injury in this lung was absent. The results thus indicate that meconium aspiration induces severe local inflammation and lung injury, but significant generalized pulmonary inflammatory damage in the pathogenesis of meconium aspiration syndrome is unlikely.

Topics: Animals; Animals, Newborn; Blood Pressure; Humans; Infant, Newborn; Lung; Meconium; Meconium Aspiration Syndrome; Organ Size; Pneumonia; Swine

To compare the predictive value of intrapartum fetal pulse oximetry to that of fetal scalp blood pH for an abnormal neonatal outcome in the case of thick meconium.. A prospective multicenter observational study was performed from June 1994 to November 1995. Fetal oxygen saturation was monitored using a Nellcor N-400 fetal pulse oximeter in case of abnormal FHR. The last readings of fetal oxygen saturation and fetal scalp blood pH before birth were used to assess the ability of both techniques to predict an abnormal neonatal status.. At a 30% cutoff, the negative predictive value of fetal oxygen saturation was not altered in case of meconium when compared to clear amniotic fluid (79 and 83%, respectively). Fetal scalp blood pH at a 7.20 threshold had a poor negative predictive value in case of meconium when compared to clear amniotic fluid (56% versus 88%, respectively). The receiver operator characteristic curve showed similar performance of fetal scalp blood pH and pulse oximetry in cases with clear amniotic fluid. In cases with meconium, the performance of fetal scalp blood pH was poor, whereas that of pulse oximetry remained unchanged. In three cases with meconium below the vocal cords, a drop in fetal oxygen saturation was observed during labor whereas fetal scalp blood pH remained within normal values.. The predictive value of fetal scalp blood pH is poor in case of meconium, whereas the predictive value of pulse oximetry seems to be unchanged in this situation.

Topics: Amniotic Fluid; Female; Fetal Blood; Fetus; Humans; Hydrogen-Ion Concentration; Infant Mortality; Infant, Newborn; Labor, Obstetric; Meconium; Meconium Aspiration Syndrome; Oximetry; Oxygen; Pregnancy; ROC Curve; Scalp

Clear amniotic fluid is frequently considered a reassuring sign during labor. Our aim was to examine the incidence of meconium that can only have been passed intrapartum and to determine its neonatal associations and whether its absence is a useful sign.. This was a prospective cohort study of 8394 "low risk" laboring women at term with clear amniotic fluid at early amniotomy.. Meconium was passed in 5.2% of labors but was not detected until delivery of the fetal head in 51.5% of these. It was associated with moderate-severe acidosis (odds ratio [OR] 4.40; 95% confidence interval [CI] 3.21, 6.03), low Apgar score at 5 minutes (OR 6.49; 95% CI 2.73, 15.44), and neonatal seizures (OR 4.33; 95% CI 3.17, 5.93). However, the sensitivity for these outcomes of the intrapartum passage of meconium and, particularly, its detection before delivery was very poor.. Although correlated with adverse neonatal outcomes, most affected infants had clear amniotic fluid throughout labor. The presence of clear amniotic fluid is an unreliable sign of fetal well-being.

Topics: Adult; Amniotic Fluid; Cohort Studies; Confidence Intervals; Delivery, Obstetric; Female; Fetal Distress; Fetal Monitoring; Gestational Age; Humans; Infant, Newborn; Meconium; Meconium Aspiration Syndrome; Odds Ratio; Predictive Value of Tests; Pregnancy; Pregnancy Outcome; Prevalence; Prospective Studies; Reference Values; Risk Assessment

To explore the epidemiology of meconium stained amniotic fluid pero-delivery.. 6,206 one-fetal delivery cases were divided into meconium stained amniotic fluid and normal amniotic fluid groups. Statistics were analysed on two groups using Cohort study.. Incidence of meconium stained amniotic fluid was 16.4%. There was no significant difference on maternal medical complication between two groups. The percentage of parity, gestational week > or = 42 weeks and big birth weight were higher in meconium stained amniotic fluid group than that in normal amniotic fluid group (P < 0.001). The average Apgar score in meconium stained amniotic fluid group was lower than that in normal amniotic fluid group (P = 0.001). The percentage of stillbirth, low birth weight and transferred newborn care unit in meconium stained amniotic fluid group were higher than that in normal amniotic fluid group (P < 0.001).. The relative factors on meconium stained amniotic fluid were maternal parity, gestational weeks > or = 42 weeks and big birth weight. No correlation between meconium stained amniotic fluid and maternal medical complication. Morbidity of newborn baby was higher in meconium stained amniotic fluid. Meconium stained amniotic fluid is a important clinical factor on evaluating pregnancy outcome.

Topics: Adult; Amniotic Fluid; Apgar Score; China; Cohort Studies; Female; Fetal Distress; Fetal Weight; Gestational Age; Humans; Infant, Newborn; Infant, Premature; Meconium; Meconium Aspiration Syndrome; Pregnancy; Pregnancy Outcome

Meconium aspiration syndrome has been for many years an important cause of neonatal respiratory distress in newborn babies and sporadically reported in animals. This investigation was designed to study the ultrastructural and morphometric changes in the lungs of neonatal rats following the intratracheal inoculation of meconium. Seven-day-old Fischer-344 rats (n = 24) were randomly allocated in two groups. One group was intratracheally inoculated with saline solution and the second group received homologous meconium. Neonates were euthanatized at 1, 3 and 7 postinoculation days (PID) and lungs were examined by light and electron microscopy. Saline solution did not induce any ultrastructural changes in the lung. In contrast, meconium induced deciliation, recruitment of neutrophils and pulmonary alveolar macrophages to the bronchoalveolar space, intravascular sequestration of neutrophils and aggregation of platelets at PID 1 and 3. Other ultrastructural changes at PID 1 and 3 included interstitial edema and escape of red cells and fibrin into the alveolar space and interstitium. Interstitial edema and sequestration of neutrophils were responsible for the significant increase in thickness of alveolar septa. At PID 7 there was hyperplasia and enlargement of type II pneumocytes as well as interstitial proliferation of mesenchymal cells with intra-alveolar fibrosis. It was concluded that intratracheal inoculation of meconium in neonatal rats induces acute ultrastructural changes followed by a reparative response.

Topics: Animals; Animals, Newborn; Bronchi; Cell Division; Female; Glutaral; Humans; Infant, Newborn; Lung; Male; Meconium; Meconium Aspiration Syndrome; Microscopy, Electron; Paraffin Embedding; Pulmonary Alveoli; Pulmonary Edema; Rats; Rats, Inbred F344; Tissue Fixation; Trachea

To understand the pathogenesis of meconium aspiration syndrome, we compared the pulmonary and inflammatory effects of the water and lipid extracts of human meconium instilled into the lungs of newborn piglets. The piglets were artificially ventilated, made hypoxemic, and randomized into three groups. At start of reoxygenation, 3 ml/kg of one of the following mixtures was instilled intratracheally: (1) meconium (n = 12); (2) water extract of meconium (n = 12), and (3) lipid extract of meconium (n = 12). During 8 h of reoxygenation, hemodynamics, pulmonary gas exchange, lung mechanics, and interleukin-8 concentrations in tracheobronchial aspirates were monitored. Oxygenation index (p = 0.04) and mean airway pressure (p = 0.04) increased more in the lipid extract group than in the water extract group. Dynamic compliance and mean arterial blood pressure decreased (p < 0.05) in the meconium and lipid extract groups, but not in the water extract group. At 8 h of reoxygenation, the interleukin-8 concentration in the tracheobronchial aspirates was three times higher in the lipid extract group as compared with the water extract group (110 +/- 102 vs. 37 +/- 27 pg/ml; p = 0.02). In conclusion, pulmonary dysfunction in meconium aspiration syndrome is caused by both the water- and lipid-soluble fractions of meconium, with stronger inflammatory and more detrimental effects promoted by the lipid extract than the water extract.

Topics: Animals; Animals, Newborn; Blood Pressure; Humans; Hypoxia; Infant, Newborn; Inflammation; Interleukin-8; Lipids; Lung; Lung Diseases; Meconium; Meconium Aspiration Syndrome; Oxygen; Pulmonary Gas Exchange; Respiration, Artificial; Solubility; Swine; Tissue Extracts; Vascular Resistance; Water

To estimate the prevalence of meconium-stained amniotic fluid and meconium aspiration syndrome, as well as the differences in case fatality from meconium aspiration syndrome, between non-Hispanic black and non-Hispanic white infants.. We studied non-Hispanic black and non-Hispanic white live births with weights greater than 2.5 kg and gestational ages greater than 35 weeks, using the linked US birth and infant death cohorts for three periods: 1989-1991, 1995-1997, and 1998-2000. We used logistic regression to estimate the risks of meconium-stained amniotic fluid and meconium aspiration syndrome and to estimate the case fatality of meconium aspiration syndrome by maternal race, birth weight, period, and pregnancy complications.. Risk of meconium-stained amniotic fluid was 80% higher in non-Hispanic blacks when compared with non-Hispanic whites (birth weight-adjusted odds ratio [OR], 1.81, 95% confidence interval [CI] 1.80, 1.82). The prevalence of pregnancy complications did not explain this racial disparity. Risk of meconium aspiration syndrome in non-Hispanic blacks was 67% higher when compared with non-Hispanic whites (birth weight-adjusted OR 1.67, 95% CI 1.64, 1.70). The case fatality rate of meconium aspiration syndrome was similar between non-Hispanic blacks and non-Hispanic whites in the three periods, with rates of 15.5, 15.2, and 11.2 per 1000 in non-Hispanic blacks and 13.5, 11.2, and 10.1 per 1000 in non-Hispanic whites in 1989-1991, 1995-1997, and 1998-2000, respectively.. Our results suggest that when compared with non-Hispanic whites, non-Hispanic blacks are at significantly greater risk for meconium-stained amniotic fluid and meconium aspiration syndrome but not for meconium aspiration syndrome case fatality.

Topics: Amniotic Fluid; Black People; Confidence Intervals; Female; Humans; Infant, Newborn; Male; Meconium; Meconium Aspiration Syndrome; Odds Ratio; Pregnancy; Pregnancy Complications; Prevalence; Risk Factors; United States; White People

To evaluate dose response of inhaled nitric oxide (iNO) for surfactant-treated rabbits with meconium aspiration-induced acute lung injury (ALI) and hypoxemic respiratory failure (HRF), and variation of measured iNO by continuous NO delivery in pressure support ventilation (PSV).. Adult rabbits (2.0 - 3.5 kg, n = 33) were randomized to receive intratracheal meconium instillation for 30 min and subjected to following treatment (n = 6 - 8). There were 4 groups: Control (C); NO, iNO at 1, 10, 20 and 40 x 10(-6) each for 60 min at 30 min interval of disconnection; Surf, intratracheal instillation of porcine lung surfactant phospholipids (100 mg/kg); SNO, both iNO and surfactant as in the NO and Surf groups; and a normal group (N), which did not undergo meconium aspiration but received sham deliveries of normal saline. All the animals were treated with PSV for 6 h. iNO levels at different input and sampling sites in the NO and SNO groups were detected by on-line chemiluminescent technique. The blood gas and lung mechanics were measured during the experiments every 2 h.. (1) Meconium aspiration induced ALI and severe HRF (PaO(2)/FiO(2) < 200 mmHg) and depressed dynamic compliance of respiratory system (Cdyn) and airway resistance (Raw). In both Surf and NO groups modestly improved oxygenation was observed. In the SNO, values for PaO(2)/FiO(2) were improved from (185 +/- 39) mmHg at baseline to (301 +/- 123) mmHg at 6 h, while moderate or transient improvement was observed in both Surf and NO groups. Cdyn and Raw were only improved for short time in the Surf, NO and SNO groups. iNO had a mild response at 1 x 10(-6) to good response at 10 and 20 x 10(-6), but no further improvement occurred at 40 x 10(-6). The response of iNO in NO group was relatively transient compared to the SNO group. (2) When iNO was connected to the ventilator circuit, the connected site should be placed before humidifier to minimize fluctuation of iNO concentration, and sampling site for iNO monitoring should be placed adequately to eliminate artifact.. iNO synergistically improved surfactant effects on oxygenation and lung mechanics. Continuous supply of iNO with non-continuous flow ventilator provided stable NO within accepted target range with least variation.

Topics: Administration, Inhalation; Animals; Drug Therapy, Combination; Female; Humans; Infant, Newborn; Lung; Male; Meconium; Meconium Aspiration Syndrome; Nitric Oxide; Phospholipids; Pulmonary Surfactants; Pulmonary Ventilation; Rabbits; Random Allocation; Respiratory Distress Syndrome; Treatment Outcome

To explore the relationship between meconium-stained amniotic fluid and Fifty-six women of cesarean section with intact membrane and intra-amniotic infection.. without parturient were divided into 3 groups according to the property of amniotic fluid (no meconium, I to approximately II degree meconium stainedness, and III degree mecomium stainedness). The content of interleukin-6 in amniotic fluid was measured with ELISA. The infiltration of inflammatory cells in the placenta and its membrane was determined by the pathological diagnosis. The neonatal Apgar score and puerperial infection after the surgery were analyzed.. There were no significant differences in the content of IL-6 in amniotic fluid and in the infiltration of inflammatory cells among the 3 groups. But the rate of neonatal asphyxia in the meconium-stained cases was significantly higher than that without meconium.. Meconium-stained amniotic fluid is a marker of fetal distress, but it is not related to intra-amniotic infection.

Topics: Adult; Amniotic Fluid; Bacterial Infections; Cesarean Section; Chorioamnionitis; Female; Fetal Distress; Fetal Monitoring; Humans; Infant, Newborn; Meconium; Meconium Aspiration Syndrome; Pregnancy; Pregnancy Complications, Infectious

Acute lung injury induced by meconium aspiration is characterized by rapidly developing pulmonary inflammation with influx of activated polymorphonuclear cells. To evaluate the role of meconium in the activation of these invading cells, we described the oxidative capacity of circulating neutrophils after intratracheal administration of thick human meconium in pigs. We also examined the direct effects of varying meconium concentrations on the oxidative burst of human neutrophils in vitro. In neutrophils isolated from meconium-insufflated pigs, phorbol myristate acetate stimulation led to an average 11.7-fold increase in production of reactive oxygen species, measured by chemiluminescence, whereas the increase in control cells from saline-instilled pigs was only 3.1-fold, p =.012 between the groups. Activation of unstimulated human leukocytes by meconium resulted in a dose-dependent response. The lowest meconium concentration (0.2 mg/mL) had an inhibitory effect on neutrophil activation, whereas higher concentrations of meconium (1 and 2 mg/mL) increased neutrophil oxygen radical production progressively. These results thus indicate that moderate and high concentrations of aspirated meconium rapidly activate circulating neutrophils with a resulting oxidative burst contributing to pulmonary tissue injury, whereas low contamination of the aspirated material may in fact suppress the development of oxidative lung injury.

Topics: Animals; Animals, Newborn; Female; Humans; Infant, Newborn; Male; Meconium; Meconium Aspiration Syndrome; Neutrophils; Respiratory Burst; Swine

Fetal pulse oximetry is a minimally invasive, simple technique which continuously helps to reflect in utero well-being. The presence of meconium in the amniotic fluid may be a clinical sign of fetal hypoxaemia. Amnioinfusion has a beneficial effect on the incidence of meconium aspiration syndrome (MAS), and the presence of meconium below the level of the vocal cords.. We studied the impact of amnioinfusion combined with fetal pulse oximetry on the incidence of meconium aspiration syndrome and operative delivery.. The retrospective analysis revealed that the presence of meconium below the level of vocal cords was significantly reduced. The frequency of cesarean section is decreased, however, it did not reach statistical significance.. Fetal pulse oximetry may be used in combination with amnioinfusion and cardiotocography (CTG) to reduce the risk of meconium aspiration syndrome and the number of instrumental deliveries and improve perinatal outcome.

Topics: Adolescent; Adult; Amniotic Fluid; Cardiotocography; Cesarean Section; Delivery, Obstetric; Female; Humans; Infant, Newborn; Meconium; Meconium Aspiration Syndrome; Oximetry; Pregnancy; Pregnancy Outcome; Retrospective Studies; Time Factors

Over a 7 month period 131 cases with intrapartum draining of meconium-stained liquor (MSL) were reviewed and the neonatal outcome compared to that of all deliveries during the same time. Mean Apgars were significantly lower and the proportion of neonates with poor Apgar scores was higher if thick meconium was present, but not for thin meconium. Prolonged labour was more common and associated with a particularly worse outcome in the MSL group. Caesarean sections were performed twice as frequently, failure to progress being the indication in more than half the cases. Close monitoring of labour in the presence of MSL (particularly thick MSL) is important to detect failure to progress and fetal distress early.

Topics: Adult; Amniotic Fluid; Apgar Score; Case-Control Studies; Cesarean Section; Female; Humans; Infant, Newborn; Meconium; Meconium Aspiration Syndrome; Medical Records; Obstetric Labor Complications; Pregnancy; Pregnancy Outcome; Pregnancy, Prolonged; Retrospective Studies; Rural Health; Zimbabwe

Topics: Ethics; Humans; Infant, Newborn; Informed Consent; Intubation, Intratracheal; Meconium; Meconium Aspiration Syndrome; Neonatology; Random Allocation; Research Design; Suction; Treatment Outcome

To examine the possible maternal and fetal variables associated with meconium aspiration syndrome in labors with thick meconium.. The fetal heart rate tracings, cord pH, Apgar scores and maternal risk factors were evaluated in singleton pregnancies with vertex presentation and thick meconium in labor. The study included 33 consecutive fetuses which developed a moderate or severe meconium aspiration syndrome and 104 consecutive fetuses which had a favorable outcome.. Significant differences between fetuses with meconium aspiration syndrome and healthy fetuses were found in the following parameters: baseline FHR (154+/-17 vs. 136+/-10, P<0.0001), small accelerations/30 min (1.47+/-1.52 vs. 3.04+/-1.2, P<0.0001), large accelerations/30 min (1.46+/-1.96 vs. 3.5+/-2.31, P<0.0003), decelerations/30 min (4.9+/-3.9 vs. 2.4+/-2.1, P<0.0034), number of fetuses with reduced beat-to-beat variability (9/33 vs. 0/104, P<0.0001), cord pH (7.21+/-0.09 vs. 7.33+/-0.08, P<0.0013) and Apgar scores at 1 min (5+/-2 vs. 8+/-1, P<0.0001) and Apgar scores at 5 min (8+/-2 vs. 9.7+/-0.6, P<0.0001). Maternal risk factors were found in two of 33 sick infants and in 13 of 104 healthy infants.. Thick meconium by itself is not associated with adverse fetal outcome. However, the incidence of meconium aspiration syndrome increases in cases of a non-reassuring FHR.

Topics: Apgar Score; Female; Fetal Blood; Heart Rate, Fetal; Humans; Hydrogen-Ion Concentration; Infant, Newborn; Labor Presentation; Labor, Obstetric; Meconium; Meconium Aspiration Syndrome; Pregnancy; Pregnancy Complications; Retrospective Studies; Risk Factors

Meconium aspiration causes intensive inflammatory reactions in the lungs, and may lead to neonatal respiratory disorder. Infiltrated inflammatory cells, particularly macrophages, play an important role in such an inflammation. A rat alveolar macrophage cell line (ATCC8383) was exposed to meconium alone or in combination with dexamethasone, budesonide, or interferon-gamma. Nitric oxide (NO) accumulation in the supernatant of the cell culture was detected by Griess reaction, and mRNA of inducible NO synthase (iNOS) expression was detected by reverse transcriptase-PCR. Nuclear factor-kappa B was analyzed by electrophoretic mobility shift assay, and iNOS location and nuclear factor-kappa B transactivation were determined by immunostaining. Our results showed that meconium was capable of inducing production of NO and expression of iNOS in alveolar macrophages in a dose- (1-25 mg/mL, p < 0.05) and time- (4-48 h, p < 0.05) dependent manner. This capability of meconium could be further enhanced in the presence of interferon-gamma (100 IU/mL, p < 0.05). Budesonide (10(-4)-10(-10) M) or dexamethasone (10(-4)-10(-6) M) effectively inhibited the meconium-induced NO production (p < 0.05). Using the protein synthesis inhibitor cycloheximide, we demonstrated that meconium directly induced iNOS in macrophages. Furthermore, meconium also triggered nuclear factor-kappa B activation, a mechanism possibly responsible for the iNOS expression. Our findings suggest that meconium is a potent inflammatory stimulus, resulting in iNOS expression, leading to overproduction of NO from the macrophages, which may be of pathogenic importance in meconium aspiration syndrome. In vitro steroids down-regulated the iNOS expression, thus suggesting a potential to down-regulate NO-mediated inflammation in neonates with meconium aspiration syndrome.

Topics: Animals; Anti-Inflammatory Agents; Base Sequence; Budesonide; Cell Line; Dexamethasone; DNA Primers; Gene Expression; Glucocorticoids; Humans; Infant, Newborn; Macrophages, Alveolar; Meconium; Meconium Aspiration Syndrome; NF-kappa B; Nitric Oxide; Nitric Oxide Synthase; Nitric Oxide Synthase Type II; Rats; RNA, Messenger

Our aim was to compare the clinical characteristics of meconium aspiration syndrome in cases with pH > or =7.20 and in those with pH <7.20.. Medical records of diagnostic codes from the International Classification of Diseases, Ninth Revision, were used to identify neonates with severe meconium aspiration syndrome who had been delivered at our institution from 1994 through 1998. Severe meconium aspiration syndrome was defined as a mechanical ventilator requirement of >48 hours. Clinical data including neonatal outcomes of cases of meconium aspiration syndrome associated with umbilical pH > or =7.20 at delivery were compared with data on outcomes of cases with pH <7.20.. During this 4-year study period, 4985 singleton term neonates were delivered through meconium-stained amniotic fluid. Forty-eight cases met all study criteria, and pH values at delivery were as follows: pH > or =7.20, n = 29, and pH <7.20, n = 19. There were no differences between groups in the incidence of clinical chorioamnionitis, in the presence of meconium below the vocal cords, or in birth weight. Neonates with meconium aspiration syndrome and umbilical pH > or =7.20 at delivery developed seizures as often as those with pH <7.20 (20.1% vs 21.1%; P = 1.0).. Normal acid-base status at delivery is present in many cases of severe meconium aspiration syndrome, which suggests that either a preexisting injury or a nonhypoxic mechanism is often involved.

Topics: Acid-Base Equilibrium; Adult; Birth Weight; Chorioamnionitis; Delivery, Obstetric; Female; Humans; Hydrogen-Ion Concentration; Incidence; Infant, Newborn; Meconium; Meconium Aspiration Syndrome; Pregnancy; Seizures; Vocal Cords

To evaluate the null hypothesis that there would be no difference in neonatal outcome in infants who underwent DeLee suction vs. those who underwent bulb suction when thick meconium was present. This difference was defined as a one-day difference in length of stay, two-point difference in the five-minute Apgar score or significant difference in blood gases.. A power calculation based on a one-day length of stay found that 115 patients would be needed in each arm. A cohort of 115 consecutive deliveries with the presence of thick meconium was reviewed during each time period when DeLee suction was utilized and then matched with deliveries that used bulb suction.. Two hundred thirty charts were reviewed. Length of stay, one-minute Apgar score, five-minute Apgar score, blood gases, gestational age and incidence of amnioinfusion were compared. There was no significant difference in any variable. Meconium aspiration syndrome in the period studied remained stable at < 1%.. There was no significant clinical change in neonatal outcome with the abandonment of nasopharyngeal DeLee suction on the perineum when meconium was present. We recommend the use of bulb suction as routine obstetric practice even in the presence of thick meconium.

Topics: Apgar Score; Cohort Studies; Delivery, Obstetric; Endpoint Determination; Humans; Infant, Newborn; Length of Stay; Meconium; Meconium Aspiration Syndrome; Nasopharynx; Perineum; Retrospective Studies; Suction; Treatment Outcome

The delivery room management of infants born through meconium stained amniotic fluid (MSAF) remains controversial. The aim of this prospective study was to evaluate maternal and neonatal characteristics of MSAF infants and the incidence of meconium aspiration syndrome (MAS) in routine delivery room management which reserved selective intubation for depressed/asphyxiated babies. Between October 1993 and September 1997, a consecutive sample of 3745 full-term infants was analyzed. Of these, 361 were MSAF infants. No significant difference in maternal age, parity, gestational age, sex, low 1 and 5 minute Apgar scores, metabolic acidemia, or need for endotracheal intubation was found between MSAF and non-MSAF infants. Only one of the MSAF infants (0.28%), who needed intubation, developed MAS. Identification of postterm pregnancy and prenatal asphyxia is the best prevention of MAS.

Topics: Adult; Amniotic Fluid; Apgar Score; Asphyxia Neonatorum; Female; Gestational Age; Humans; Infant, Newborn; Intubation, Intratracheal; Male; Meconium; Meconium Aspiration Syndrome; Prospective Studies

Studying the effects of toxic and infective compounds on the respiratory system requires a reliable method for delivering inoculum into the distal region of the lung. Although transoral intratracheal inoculation methods have been well documented for adult rats, to the authors' knowledge, a reliable method has not been validated for neonatal rats. The purpose of the study reported here was to develop a simple method for transoral inoculation in rat neonates.. Seven-day-old Fischer 344 rats were anesthetized with halothane, and a spinal needle was inserted in the tracheal lumen, by use of illumination and a modified otoscope. Meconium was injected into the lungs as a marker, and the neonates were kept under close observation. After euthanasia at 24 h, lungs were removed and fixed in formalin, and the microscopic distribution of the inoculum was assessed in the left, right cranial, middle, median, and caudal lung lobes.. Microscopic examination of lungs indicated that intratracheal inoculation was achieved in 100% of neonatal lungs and the inoculum was consistently distributed in the alveoli of all pulmonary lobes. Important complications or mortality were not observed in the neonates.. Intratracheal inoculation of neonatal rats is possible by use of a modified otoscope for transoral illumination. This technique is simple and reproducible and ensures, without complications, widespread distribution of inoculum in the lungs of neonatal rats.

Topics: Anesthesia, Inhalation; Animals; Animals, Newborn; Cannibalism; Drug Administration Routes; Equipment Design; Female; Humans; Infant, Newborn; Lighting; Lung; Meconium; Meconium Aspiration Syndrome; Models, Animal; Otoscopes; Particle Size; Pilot Projects; Pregnancy; Rats; Rats, Inbred F344; Reproducibility of Results; Trachea; Viscosity

Amnioinfusion reduces the risk of meconium aspiration by the infants of women with thick meconium staining of the amniotic fluid. The benefits are clear in facilities with high baseline rates of meconium aspiration, and are therefore likely to outweigh the risk of uncommon but serious maternal side-effects. Larger randomized trials are needed to determine more precisely the relative risks and benefits in facilities with low baseline rates of meconium aspiration. The addition of antibiotics to the infusate has not been shown to reduce the risk of sepsis related to meconium.

Topics: Amniotic Fluid; Female; Fetal Diseases; Humans; Infant, Newborn; Injections; Isotonic Solutions; Meconium; Meconium Aspiration Syndrome; Pregnancy; Ringer's Lactate; Sodium Chloride

Recent studies indicate that the risk of meconium-stained amniotic fluid (MSAF) varies in different ethnic groups. This study prospectively examined the ethnic variation of MSAF and meconium aspiration syndrome, adjusting for gravidity, gestational age (GA), and birth weight.. The study population consisted of 6901 consecutive live births and included 31 different nationalities, seven main ethnic (race) groups, gravidity between 1 and 19, GA between 22 and 44 weeks, and birth weights between 350 and 6292 gm.. The overall incidence of MSAF was 19% (13% thin, 6% thick). The prevalence of meconium aspiration syndrome was 5% in thick MSAF and none in thin MSAF. The incidence of MSAF differs significantly by ethnicity (14% to 30%), gravidity (17% to 23%), GA (6% to 46%), and birth weight (11% to 28%). Multivariate logistic regression analysis using the same variable showed that being black African, post-term, with a gravidity of > or = 7 and a birth weight of > or = 4000 gm significantly increased the chance for MSAF but not meconium aspiration syndrome. After controlling for these clinical variables, the black African infants had a higher percentage of MSAF at all GAs compared with the other ethnic groups.. This study showed that the risk of MSAF varied by ethnicity and increased with higher gravidity, a GA of > 42 weeks, and a birth weight of > or = 4000 gm The higher incidence of MSAF without an increase in meconium aspiration syndrome in some ethnic groups may indicate advancing maturity of the gastrointestinal system in black ethnic groups compared with others of the same GA.

Topics: Amniotic Fluid; Asian People; Black People; Cohort Studies; Confidence Intervals; Female; Gestational Age; Humans; Incidence; Infant, Newborn; Logistic Models; Male; Meconium; Meconium Aspiration Syndrome; Multivariate Analysis; Odds Ratio; Pregnancy; Prospective Studies; Risk Assessment; United Arab Emirates; White People

Meconium aspiration syndrome is related to mechanical obstruction of the airways and subsequent chemical pneumonitis. It has also been suggested that meconium causes inhibition of surfactant function. To assess its inhibitory effect on surfactant function in vitro, we used a stable microbubble (SM) test that was thought to reflect the adequacy of pulmonary surfactant. The mixtures were prepared by adding serial dilutions of human meconium to various concentrations of Surfactant-TA (Surfacten). The SM count at each concentration of surfactant significantly increased with the increasing concentration of surfactant. This shows that the SM test closely reflects the quantified function of surfactant. When various concentrations of meconium were added to the surfactant concentration of 0.05 mg/ml and 0.25 mg/ml, the SM test results were decreased even at low concentrations of meconium. Also the increase in the meconium concentration caused a decrease in the SM test result, which was dependent on the surfactant and the meconium concentration, accordingly. These results suggest that meconium inhibits surfactant function.. The stable microbubble test is an effective indirect method that tests the changes in surfactant quantity. In the in vitro experiment, we observed an inhibitory effect of meconium on the surfactant activity using the stable microbubble test.

Topics: Biological Products; Humans; In Vitro Techniques; Infant, Newborn; Inhibitory Concentration 50; Meconium; Meconium Aspiration Syndrome; Pulmonary Surfactants

The purpose of this study was to evaluate the meconium staining of amniotic fluid (AF) in term of fetal distress, meconium aspiration syndrome, and perinatal morbidity and mortality. In a prospective study at Princess Badeea Teaching Hospital from April to November 1999, women with a singleton cephalic pregnancy of completed 37-42 weeks and with no pre-defined risk factor were recruited into the study. Study patients comprised 390 (10%) patients with meconium and 400 patients as controls but with clear amniotic fluid. Virtually meconium staining of the amniotic fluid was significantly associated with poor neonatal outcome in all outcomes measures assessed. Perinatal mortality increased from 2 per 1000 births with clear AF to 10 per 1000 with meconium (P<0.001). Other adverse outcomes also increased; e. g., severe fetal acidemia, Apgar score < or = 3 at 1 min and 5 min, and meconium aspiration syndrome. Delivery by cesarean section also increased with meconium from 7-14% (P<0.001). We concluded that meconium in the amniotic fluids associated with an obstetric hazard and significantly increase risks of adverse neonatal outcomes. Women with thin meconium in the presence of normal fetal heart rate can be safely managed at the clinical level. Mod-thick meconium alone should alert the obstetrician to a high risk fetal condition. Continuous fetal heart rate monitoring during labour and reassurance of fetal well-being by acid-base assessment were most significant factors in the reduction of meconium aspiration syndrome.

Topics: Adult; Amniotic Fluid; Birth Weight; Cesarean Section; Chorioamnionitis; Female; Fetal Blood; Heart Rate, Fetal; Humans; Hydrogen-Ion Concentration; Infant, Newborn; Labor, Induced; Labor, Obstetric; Meconium; Meconium Aspiration Syndrome; Pregnancy; Pregnancy Outcome; Respiration, Artificial; Respiratory Distress Syndrome, Newborn; Suction

To discuss the significance of amnioinfusion and amniotic fluid exchange under continuous internal fetal heart rate (FHR) monitoring for management of fetal distress during labor.. 136 cases with frequent variable deceleration (VD) and meconium stained amniotic fluid during labor were divided into two groups: the study group (68 cases) and the control group (68 cases). The former were treated by amnioinfusion and amniotic fluid exchange, while oxygen inhalation, change of body position, and intravenous infusion for the control group.. In the study group, VD disappeared or relieved in 62 cases obviously, and the efficacy rate reached 91.2% (62/68). 48 cases with II degree meconium stained amniotic fluid were treated by amniotic fluid exchange, amniotic fluid became clear or turned to I degree stained in 39 cases. In the control group, VD relieved in 20 cases, the efficacy rate was 19.4%, significantly lower than that of the study group (P < 0.01). In the study group, cesarean section rate was 14.7% neonatal asphyxia 7.4% while they were 47.1% and 48.5% in the control group respectively (P < 0.01; P < 0.01). Neonatal pneumonia caused by meconium aspiration occurred in 13 cases, meconium aspiration syndrome (MAS) 8 cases, with 5 newborns died in the control group, while there was no neonatal death in the study group. There was no significant difference on puerperal morbidity between the 2 groups (P > 0.05).. Amnioinfusion and AF exchange during labor are one of the effective treatment methods for fetal distress and prevention for MAS.

Topics: Adult; Amnion; Amniotic Fluid; Female; Fetal Distress; Fluid Therapy; Heart Rate, Fetal; Humans; Infant, Newborn; Labor, Obstetric; Meconium; Meconium Aspiration Syndrome; Pregnancy; Sodium Chloride

Six full-term neonatal temporal bones, with meconium contaminated amniotic fluid aspiration of varying degrees, were serially sectioned at 20 microm and every tenth section was stained by hematoxylin eosin and mounted on slides. All stained sections were studied, the data recorded and relevant details of all compartments photographed. In addition, four normal neonate temporal bones were studied, one by serial sectioning and three by microdissection. The lateral incudomalleal and tensor folds were present in all, membrane defects in the tensor fold were seen in two normal ears. Three ears in the aspiration group had much fetal tissue present rendering Prussak's space small. Four ears with aspiration had remnants of incus intercrural (medial) folds. The amniotic fluid cellular content (AFCC) was sparse or nonexistent in the supratubal recess, Prussak's space and hypotympanum. It concentrated to the areas around the stapes, to sinus tympani and round window niche, to lower lateral attic and posterior pouch, medial attic and in lesser amounts to superior attic, mastoid antrum and air cells. Massive amounts of AFCC in tympanic isthmus and posterior pouch may lead to formation of granulation tissue and blockage of the aeration pathways to attic proper and to Prussak's space. These changes may initiate the development of chronic secretory otitis media in infants.

Topics: Amniotic Fluid; Autopsy; Ear, Middle; Fatal Outcome; Female; Humans; Infant, Newborn; Male; Meconium; Meconium Aspiration Syndrome; Mucous Membrane; Temporal Bone

The significance of meconium-stained amniotic fluid (MSAF) is discussed, both in regards to obstetric and pediatric management. The primary concerns regarding MSAF have been its significance as a sign of fetal distress/perinatal asphyxia and the prevention of associated morbidity such as meconium aspiration syndrome. The objectives of our study were: (1) To know the incidence and type of MSAF, (2) to study the associated morbidity in newborns with MSAF admitted to the Neonatal Care Unit (NCU), and (3) to analyze the perinatal differences between newborns with moderate versus thick MSAF.. A retrospective study was performed to know the incidence of MSAF in all of the deliveries in our hospital during a 4 year period. The consistency of meconium was classified into 3 classes, thin (light), moderate or thick (heavy). On the other hand, a prospective analysis was undertaken to determine the morbidity of all meconium-stained neonates admitted to our NCU during this period, mainly in relation to perinatal asphyxia, pulmonary, gastrointestinal and infectious pathology and neonatal mortality.. The presence of MASF complicates 18% of all of our deliveries with it being mild in 10.8%, moderate in 4.4% and severe in 2.8%. Of all newborns with MSAF, one third were admitted to the NCU, mainly for two reasons, association with perinatal asphyxia (124 cases) and observation of a risk of meconium aspiration syndrome (85 cases). The main neonatal morbidities associated with MSAF in our populations were perinatal asphyxia in 56.1% (32 cases of severe perinatal asphyxia and 92 non-severe), pulmonary pathology in 34% (meconium aspiration syndrome in 32 cases and other respiratory abnormalities in 43) and gastrointestinal pathology in 30.5% (transitory feeding intolerance in all cases). Four cases of meconium-stained neonates were exitus. The neonatal morbidity is significantly more frequent in relation to thick meconium and also if perinatal asphyxia is associated to MSAF.. Although the relationship between MSAF and perinatal asphyxia is controversial, their association increases neonatal morbidity. In accordance with our results, thick meconium is implicated as a risk factor influencing the well being during the intrapartum and postpartum periods.

Topics: Birth Weight; Chi-Square Distribution; Female; Gestational Age; Humans; Incidence; Infant, Newborn; Male; Meconium; Meconium Aspiration Syndrome; Prospective Studies; Retrospective Studies; Spain; Statistics, Nonparametric; Viscosity

To investigate the role of high frequency oscillation (HFO) in promoting meconium clearance from the airway, we used a commercially available ventilator configured with maximal expiratory flow exceeding inspiratory flow (asymmetric HFO or AHFO). We hypothesized that AHFO would move meconium in an expiratory direction (toward the ventilator). We first tested our hypothesis in vitro and, later, in vivo using the neonatal piglet. In vitro experiments using a Plexiglas airway confirmed meconium movement in an expiratory direction when bias ratio was > or = 2. For in vivo experiments, each piglet received a 3 mL/kg intratracheal bolus of a 44 g/100 mL meconium mixture followed by 45 min of mechanical ventilation. Then, in part 1, the piglet was placed in a 15 degree head down tilt position and randomized to either AHFO [ratio of inspiratory time/expiratory time (I:E) of 70:30] or HFO (I:E ratio of 30:70). After 30 min of either AHFO or HFO, the piglet was crossed over to the alternate strategy for an additional 30 min. For part 2, we maintained the piglet on either AHFO or HFO continuously for 4 h. Results demonstrate that, although there was a tendency for larger volumes of meconium to be aspirated from the airway during AHFO in part 1 experiments, there was no difference found in part 2. We also found no significant differences in blood gases or hemodynamic measurements between AHFO and HFO during the prolonged observation period in part 2 of our study. We conclude that AHFO is of no benefit in the treatment of meconium aspiration syndrome.

Topics: Animals; Animals, Newborn; Arteries; Blood Pressure; Carbon Dioxide; Cardiac Output; Disease Models, Animal; High-Frequency Ventilation; Humans; Hydrogen-Ion Concentration; In Vitro Techniques; Infant, Newborn; Lung; Meconium; Meconium Aspiration Syndrome; Partial Pressure; Swine

To show that intrapartum prophylactic amnioinfusion in case of oligohydramnios or particulate meconium-stained amniotic fluid could be beneficial.. From March 1st, 1993 until December 31st, 1996, 6845 women were delivered at the University Hospital of Poitiers. Patients presenting with oligohydramnios (G1) (118 patients with an amniotic fluid index below 5 cm) or a particulate meconium-stained amniotic fluid (G2)(77 patients) were included. Each group was compared with a historical control group constituted retrospectively according to the following criteria: oligohydramnios (CG1), particulate meconium-stained amniotic fluid (CG2)), age, parity, gestational age, and duration of labor. Statistical analysis was performed using the Student's t test and the Fisher's exact test when appropriate with a level of significance of p < 0.05.. The mean infused volume was 883 ml in G1 and 751 ml in G2. A significant difference was found in terms of cesarean section between G1 and CG1 (14% versus 25%, p < 0.05) and of assisted deliveries for fetal distress between G2 and CG2 (5% versus 18%, p < 0.02). No other significant difference was found between the study groups and their control for all other studied criteria. When considering more specifically the presence of meconium below the vocal cords we also find a difference between G2 and CG2 (5% versus 14%) which was not significant. No neonatal or maternal adverse effects happened in this short study.. Amnioinfusion is easy to perform during labor in case of oligohydramnios or particulate meconium-stained amniotic fluid. In case of oligohydramnios, a decreased rate of cesarean sections has been observed in the infused group. Considering patients with particulate meconium-stained amniotic fluid, less interventions for fetal distress and neonates with meconium below the vocal cords has been found in the infused group. Further prospective evaluation is needed to confirm these results in case of particulate meconium-stained amniotic fluid and to compare the advantage of prophylactic versus therapeutic amnioinfusion performed in case of oligohydramnios and abnormal fetal heart rate.

Topics: Adult; Age Factors; Amnion; Amniotic Fluid; Case-Control Studies; Cesarean Section; Female; Fetal Distress; Fluid Therapy; Gestational Age; Heart Rate, Fetal; Humans; Infant, Newborn; Injections; Labor, Obstetric; Meconium; Meconium Aspiration Syndrome; Obstetric Labor Complications; Oligohydramnios; Parity; Pregnancy; Pregnancy Complications; Pregnancy Outcome; Prospective Studies; Retrospective Studies; Time Factors

To investigate the hypothesis that meconium aspiration syndrome, the major hazard of meconium during labor, may be associated with superimposed fetal acute acidemia.. Umbilical artery blood gases were measured in 7816 term pregnancies with meconium in the amniotic fluid (AF) and the results were correlated with intrapartum and neonatal outcomes.. Sixty-nine (1%) infants developed meconium aspiration syndrome and 31 (45%) of these were in association with fetal acidemia at birth. Moreover, umbilical blood gas analysis and intrapartum events suggested that the fetal acidemia linked to meconium aspiration was an acute event rather than a long-duration process, which might be expected if meconium was itself a marker of an antecedent fetal asphyxial event.. Meconium in the AF may be a fetal environmental hazard when acidemia supervenes rather than solely a marker of preexisting fetal compromise leading to the release of meconium.

Topics: Acid-Base Imbalance; Amniotic Fluid; Asphyxia; Female; Fetal Blood; Fetal Diseases; Humans; Infant, Newborn; Meconium; Meconium Aspiration Syndrome; Pregnancy

To find out the incidence, outcome as well as antenatal, intrapartum and neonatal attributes of meconium stained amniotic fluid (MSAF).. Prospective study.. Neonatal Unit of Hospital.. 1426 live births occurring in 1500 consecutive deliveries, over one year period.. In all babies born through MSAF, thorough oropharyngeal suction as soon as the head was delivered followed by immediate intratracheal intubation and suctioning in infants depressed at birth.. 204 (14.3%) deliveries had MSAF of which thick meconium was present in 141. Hepatitis in mother, fetal distress during labor and intrauterine growth retardation were significant factors associated with MSAF. One fifth of babies born through MSAF suffered severe birth anoxia compared to 5.6% in non-MSAF group. The consistency of meconium had direct bearing on the neonatal outcome. Severe birth asphyxia (SBA) occurred in 27.0 and 6.3% of babies with thick and thin meconium staining, respectively. Meconium aspiration syndrome was observed in 9 babies of thick meconium group and 8 of these were depressed at birth. All deaths occurred in thick meconium group and were associated with SBA.. Selective approach can be adopted for babies with MSAF reserving intratracheal suctioning at birth for depressed neonate or evidence of fetal distress in utero. Rest of the neonates only need careful observation after thorough oronasopharyngeal suctioning.

Topics: Amniotic Fluid; Female; Fetal Distress; Humans; Incidence; Infant Mortality; Infant, Newborn; Male; Meconium; Meconium Aspiration Syndrome; Pregnancy; Pregnancy Complications; Prognosis; Prospective Studies; Risk Factors; Survival Rate

The aim of this observational study is to review the outcome of prophylactic intrapartum amnioinfusion (AI) in pregnancies complicated by moderate to thick meconium-stained liquor (MSL). The labour and neonatal outcome of all 298 AIs performed over a 3-year period were compared to a matched-control group of patients whose labour was complicated by moderate or thick MSL but without AI. The incidence of moderate or thick meconium below the vocal cords of the neonate were significantly lower in the AI group (6.4% and 3.4%) compared with the control group (15.4% and 6.7%). The incidence of meconium aspiration syndrome in the AI group was half (1.7%) that of the control group (3.7%), although the difference did not reach statistical significance. There was a significant higher incidence of cardiotocographic abnormalities in the AI group (30.5% versus 14.7%), with higher incidences of Caesarean section and operative vaginal deliveries. The reduction in the incidence and thickness of meconium after AI was not accompanied by any statistically significant reduction in adverse fetal outcomes such as low Apgar scores, cord pH values, admissions to and duration of admission to the neonatal unit, or the incidence of meconium-aspiration syndrome.

Topics: Adult; Amnion; Female; Humans; Infant, Newborn; Infusions, Parenteral; Meconium; Meconium Aspiration Syndrome; Pregnancy; Retrospective Studies

It is uncertain how often the passage of meconium in utero is a response to some event causing fetal distress as opposed to being simply the physiologic functioning of a maturing intestinal tract. The extent to which meconium may produce injury or inflammation in pulmonary and placental tissues after intrauterine exposure is also unclear. This study was a retrospective review of 123 cases, 79 stillborn and 44 liveborn less than one month of age, autopsied at The Johns Hopkins Hospital, and showing histologic evidence of intrauterine meconium exposure by aspirated meconium or meconium macrophages in placental tissues. Of 55 cases with pulmonary inflammation, 13 (24%) had fetal pneumonia, 5 (9%) had postnatal bronchopneumonia, and 37 (67%) had inflammation secondary to meconium aspiration. There was inflammation of the umbilical cord in 31 (41%) of the 75 cases with available slides, 11 (15%) had funisitis associated with chorioamnionitis and 18 (58%) were secondary to meconium exposure. There were 19 cases with focal injury of cord vessels from meconium, two of which had cord ulceration. Inflammation of the membranes and chorionic plate was present in 24 (33%) of the 72 cases where it could be assessed, and was due to chorioamnionitis in 11 (46%) and to meconium in 13 (54%). In general, meconium-related inflammations was much less severe in the membranes than in the cord. There were 67 (54%) cases with definite or probable evidence of fetal distress. In 38 (48%) stillborns no cause of fetal death in utero was identified and in 18 (41%) liveborns there was no known prenatal problem. The results support the concept that meconium passage in utero may occur either as a response to fetal distress or as a physiologic process. Inflammation in the lung and placental tissues, and vascular injury in the umbilical cord may arise secondary to in utero exposure to meconium.

Topics: Female; Fetal Death; Fetus; Humans; Infant, Newborn; Inflammation; Meconium; Meconium Aspiration Syndrome; Placenta; Placenta Diseases; Pneumonia; Pregnancy; Retrospective Studies; Umbilical Cord; Vascular Diseases

To determine the incidence of meconiumstaining and meconium aspiration syndrome in a maternity hospital in Colombo and to evolve a suitable protocol for management.. A prospective study of 366 meconium stained babies delivered during 1988.. Castle Street Hospital for Women, Colombo.. 113 babies developed the 'meconium aspiration syndrome' and 16 of them died.

Topics: Amniotic Fluid; Humans; Infant, Newborn; Meconium; Meconium Aspiration Syndrome; Prospective Studies

A total of 3472 deliveries were studied over a year to evaluate (i) the importance of thin meconium stained liquor (MSL) in the causation of meconium aspiration syndrome (MAS), and (ii) the efficacy of intrapartum plus endotracheal suction at birth in the prevention of MAS due to thin meconium. Two hundred and ninety four (8.5%) of deliveries had meconium stained liquor of which thin MSL was present in 101. MAS occurred in 98 babies. Thin MSL was responsible for 19.4% of cases of MAS. Inspite of intrapartum suction, a high proportion (55-78%) of infants had meconium in the trachea, though thin meconium was found in the trachea significantly less often than thick meconium. Combined intrapartum and endotracheal suction reduced the incidence of MAS due to thin meconium from 26% to 16%. MAS due to thin meconium occurred in asphyxiated as well as vigorous babies inspite of combined suction. Thin meconium accounts for a significant proportion of deliveries with MSL and causes a considerable number of cases of MAS. To prevent meconium aspiration syndrome caused by thin meconium, all neonates born through thin MSL, whether they are asphyxiated or not should undergo intrapartum suction followed by immediate endotracheal suction at birth.

Topics: Asphyxia Neonatorum; Delivery, Obstetric; Female; Humans; Incidence; Infant Care; Infant, Newborn; Meconium; Meconium Aspiration Syndrome; Mouth; Nasopharynx; Pneumonia, Aspiration; Pregnancy; Prospective Studies; Respiratory Distress Syndrome, Newborn; Suction; Trachea

Although the significance of meconium-stained amniotic fluid as a sign of fetal distress remains controversial, its presence remains a concern to both obstetricians and neonatologists since signs of asphyxia and meconium staining are associated with an increase in perinatal morbidity and mortality. The aim of this study was to evaluate the role of meconium staining of the liquor in the low-risk obstetric population in terms of fetal distress and perinatal morbidity and mortality. In a prospective cohort study at a referral hospital and at one of two municipal clinics, women with a singleton pregnancy of 37 to 42 weeks gestation and with no pre-defined risk factor were recruited into the study. Study patients comprised those with meconium staining of the liquor and controls comprised similar women but with clear liquor. Meconium staining of the liquor was associated with poor outcome in all the outcome measures assessed. Fetal heart rate (FHR) abnormality was more closely associated with adverse outcome than meconium staining, and thin meconium alone was not associated with any adverse outcome except respiratory distress. Women with thin meconium in the presence of normal FHR can therefore be safely managed at the clinic level. Thick meconium itself was a risk factor for poor outcome, more so if associated with FHR abnormality, and should be an indicator for early referral.

Topics: Amniotic Fluid; Case-Control Studies; Female; Fetal Distress; Humans; Infant, Newborn; Meconium; Meconium Aspiration Syndrome; Pregnancy; Prognosis; Prospective Studies; Reproductive History; Zimbabwe

The objective of this report was to study the effect of oxytocin augmentation in arrest disorders in the presence of thick meconium on meconium aspiration and fetal acidosis. We evaluated 3,321 singleton, term deliveries with cephalic presentation at our institution. Eight percent (253/3,321) had thick meconium in labor, and these patients comprised the study sample. Of the 253 women with thick meconium, 84 had an arrest disorder in the active phase of labor with normal fetal heart rate tracing at the time of diagnosis. Seventy-four percent (62/84) of the women with arrest were treated with oxytocin (group 1) and 26% (22/84) delivered by cesarean section without augmentation (group 2). There was a significant (p < 0.05) increase in the incidence of meconium aspiration (14.5 vs. 4.5%) and low (< 7.20) cord arterial pH (27.8 vs. 4.5%) in patients who received oxytocin compared to those who did not. Of the women who received oxytocin, 36 delivered vaginally, and 2 neonates had meconium aspiration. The remaining 26 women had cesarean sections following oxytocin augmentation and had a significantly higher (p < 0.05) frequency of meconium aspiration (26.9 vs. 4.5%) and low cord arterial pH (38.5 vs. 4.5%) compared to women who had cesarean sections without oxytocin augmentation. The findings suggest that oxytocin augmentation in arrest disorders in the presence of thick meconium may be associated with a higher risk of meconium aspiration and low umbilical cord arterial pH.

Topics: Adult; Female; Humans; Incidence; Infant, Newborn; Meconium; Meconium Aspiration Syndrome; Oxytocin; Pregnancy; Pregnancy Outcome; Uterine Inertia

To quantify the current perinatal consequences associated with intrapartum detection of meconium in the amniotic fluid (AF).. We compared retrospectively the outcomes in 8136 term singleton cephalic pregnancies with meconium and 34,573 similar pregnancies with clear AF.. Virtually all measures of adverse fetal-neonatal outcomes were significantly increased with meconium. For example, perinatal mortality increased from 0.3 per 1000 births with clear AF to 1.5 deaths per 1000 with meconium (P < .001). Most of these deaths resulted from meconium aspiration. Other unwanted outcomes also increased; eg, severe fetal acidemia at birth (umbilical artery blood pH 7.00 or less) increased from three per 1000 to seven per 1000 when meconium was diagnosed (P < .001). Delivery by cesarean also increased with meconium, from 7 to 14% (P < .001).. Meconium in the AF is an obstetric hazard with small but significantly increased risks of adverse fetal-neonatal outcomes.

Topics: Adolescent; Adult; Amniotic Fluid; Cohort Studies; Female; Humans; Infant, Newborn; Meconium; Meconium Aspiration Syndrome; Pregnancy; Pregnancy Outcome; Retrospective Studies

Topics: Amnion; Female; Humans; Infant, Newborn; Infusions, Parenteral; Meconium; Meconium Aspiration Syndrome; Obstetric Labor Complications; Oligohydramnios; Pregnancy

The fetus discharges meconium (its bowel contents) into the amniotic fluid during labour in approximately 10% of pregnancies. In about 10% of cases where meconium is passed, the fetus gasps, inhaling the sticky meconium into the upper respiratory tract. After birth, the meconium blocks the air passages in the lungs, impairing gas exchange (meconium aspiration syndrome, MAS). Up to 20% of infants suffering from MAS die and recently published studies have shown a long-term effect of MAS in causing cough and wheeze. At present, meconium is only noticed at birth or occasionally when amniotic fluid leaks past the presenting part of the fetus. We have developed a system to monitor meconium continuously during labour, using a flexible intrauterine probe. The system provides a measurement of the meconium concentration of amniotic fluid during labour every 2 min, with a 60% prediction interval of +/- 10 g l-1, and a 99% prediction interval of +/- 30 g l-1 (clinically 'thick meconium' contains around 100 g l-1). The noise of the measurement is of the order of +/- 10 g l-1, and the response to changes in the meconium concentration is from 40 to 120 s, depending on its configuration. The system also provides other obstetric variables such as fetal heart rate and uterine activity measurement, obtained from a fetal monitor. Preliminary clinical results indicate that this system can measure meconium not apparent to the attending staff; the system can detect changes in the meconium concentration of amniotic fluid; the measurements are confirmed by visual observation at delivery; and changes of meconium concentration seem to correlate with known stressful stimuli. The system therefore provides a new tool from which new variables are obtained, which can greatly enhance clinical research into the pathophysiology of meconium passage and aspiration.

Topics: Female; Fetal Monitoring; Humans; Infant, Newborn; Meconium; Meconium Aspiration Syndrome; Obstetric Labor Complications; Pregnancy; Time Factors

Human meconium components were separated into a water-methanol soluble phase containing mainly proteins and bilirubin and a chloroform soluble phase containing free fatty acids, triglycerides and cholesterol. Various amounts of original meconium, the water-methanol soluble fraction or the chloroform soluble fraction were added to standard suspensions of porcine surfactant (Curosurf). In a pulsating-bubble or Wilhelmy-balance system, meconium and its subfractions inhibited surfactant activity, but the chloroform soluble fraction had the highest specific inhibitory activity. Original meconium in saline (130 or 65 mg/ml) was instilled into the airways of ventilated near-term newborn rabbits (dose 6 ml/kg). Lung-thorax compliance was reduced by 38% in animals aspirating the higher dose and by 27% in the low-dose group. Histological sections showed intra-alveolar accumulation of fine meconium particles in experimental animals, but no plugging of larger airways. We conclude that respiratory failure from meconium aspiration may be mediated, in part, by inactivation of surfactant.

Topics: Adsorption; Animals; Biological Products; Blood Proteins; Humans; Infant, Newborn; Lung; Lung Compliance; Meconium; Meconium Aspiration Syndrome; Phospholipids; Pulmonary Surfactants; Rabbits; Surface Tension; Swine

"Meconium aspiration syndrome" is a condition resulting in respiratory distress and the occasional death of newborn human beings. A retrospective study was conducted on 52 calves that were submitted for postmortem examination to the Atlantic Veterinary College, Charlottetown, Prince Edward Island, Canada. These calves died of infectious and noninfectious diseases within the first 2 weeks of life due to a variety of causes. The most common cause of death was infectious enteric disease. Histologic examination of lungs revealed that 42.5% of calves had evidence of meconium, squamous cells, or keratin in the lung. There was considerable variation in the magnitude of histologic changes in lungs containing aspirated material. Typically, affected lungs had only a few inconspicuous pieces of meconium, keratin, and squamous cells within bronchoalveolar spaces. Sporadically, the entire lumen of airways was obliterated by aspirated material. Lungs with aspirated material had a mild but diffuse alveolitis characterized by exudation of a few neutrophils, macrophages, and occasional multinucleated giant cells. Obstruction of small airways and focal atelectasis were also observed. Similar lesions have been reported in human meconium aspiration syndrome. It is concluded that histologic changes similar to those of human meconium aspiration syndrome occur commonly in calves that die within 2 weeks of birth. Further studies involving healthy age-matched calves are required to evaluate the clinicopathologic significance of meconium aspiration in this species.

Topics: Animals; Cattle; Cattle Diseases; Epithelial Cells; Humans; Infant, Newborn; Keratins; Lung; Meconium; Meconium Aspiration Syndrome; Retrospective Studies

Topics: Asphyxia; Fetal Diseases; Humans; Infant, Newborn; Meconium; Meconium Aspiration Syndrome; Models, Biological; Pharynx; Suction; Trachea

Topics: Humans; Infant, Newborn; Intubation, Intratracheal; Meconium; Meconium Aspiration Syndrome; Research Design; Suction; Trachea

Topics: Humans; Infant, Newborn; Intubation, Intratracheal; Meconium; Meconium Aspiration Syndrome; Suction; Trachea

Topics: Humans; Infant, Newborn; Intubation, Intratracheal; Meconium; Meconium Aspiration Syndrome; Retrospective Studies; Suction; Trachea

The cause of fetal distress and neonatal respiratory distress (RD) in association with meconium-stained liquor is not always clear. To clarify this, a prospective study was undertaken in a tertiary referral maternity hospital for 1 year. In all infants born after meconium-stained liquor who developed RD, evidence was sought for 1) fetal distress (from the cardiotocograph (CTG), the cord blood pH, the Apgar score and the asphyxial complications in the neonate) 2) causes of fetal distress (including maternal risk factors, fetal infection and fetal malnutrition) 3) causes of respiratory distress (including meconium aspiration syndrome (MAS), persistent pulmonary hypertension of the newborn (PPHN) and infection). Of 4,026 livebirths, 717 (17.8%) had meconium-stained liquor and 44 term and 5 preterm infants developed RD. In the 44 term infants, there was frequent evidence of fetal distress possibly caused by previously unrecognized factors such as fetal malnutrition with reduced neonatal skinfold thickness in 35% triceps and 41% subscapular measurements, and histological chorioamnionitis (CA) in 74%. The cause for respiratory distress was identified in only 48% of infants, and included clinical evidence of PPHN (41%), MAS (16%) and infection (2%). However in preterm infants, 80% had definite or suspected infection. The findings indicate that fetal distress is common in infants who develop respiratory distress after meconium-stained liquor. A role for histological CA and reduced nutrition in the fetus, as factors contributing to the vulnerability of the term infant to intrapartum fetal distress, is suggested.

Topics: Apgar Score; Chorioamnionitis; Female; Fetal Blood; Fetal Diseases; Fetal Distress; Heart Rate, Fetal; Hospitals, Maternity; Humans; Infant, Newborn; Infant, Premature; Kidney Diseases; Meconium; Meconium Aspiration Syndrome; New South Wales; Nutritional Status; Persistent Fetal Circulation Syndrome; Pregnancy; Prospective Studies; Radiography; Respiratory Distress Syndrome, Newborn; Risk Factors; Sepsis; Skinfold Thickness

Determination of the percent by volume of the solid component of meconium (the "meconiumcrit") provides a more objective method of characterizing the type of meconium. In a study of 106 women with meconium-stained amniotic fluid, 61 (58%) had thin meconium, 36 (34%) had moderate meconium, and nine (8%) had thick meconium. There was no correlation between the type of meconium and newborn acidemia (umbilical artery pH, less than 7.20)--13%, 19%, and 11%, respectively. None of the newborns with either thin or thick meconium had 1-minute Apgar scores of less than or equal to 3 and only two with moderate meconium had such Apgar scores; none had an Apgar score of less than or equal to 3 at 5 minutes. None of the newborns with thin or moderate meconium had meconium aspiration syndrome, although two of nine infants with thick meconium did have meconium aspiration syndrome. All newborns subsequently did well and left the hospital in good condition. There would appear to be no correlation between the consistency of meconium and recently reported criteria for defining birth asphyxia.

Topics: Apgar Score; Asphyxia Neonatorum; Humans; Infant, Newborn; Meconium; Meconium Aspiration Syndrome

A combined obstetric-pediatric approach to the management of deliveries complicated by meconium-stained amniotic fluid has been recommended to decrease the incidence of meconium aspiration syndrome. Although pharyngeal suction with a DeLee catheter is generally recommended, many obstetricians prefer to use a bulb syringe for suction at the perineum. A thorough review of the literature reveals no prospective studies in humans comparing the two techniques. In the present study, these two techniques of pharyngeal suction were prospectively compared at deliveries complicated by meconium-stained amniotic fluid. Of the total 2874 deliveries, 127 (4%) were complicated by moderate or thickly meconium-stained amniotic fluid, and 107 of these were included in the study. There were 53 infants in the DeLee-suctioned group and 54 in the bulb-suctioned group. Of the 107 studied infants, four (4%) developed meconium aspiration syndrome, three in the DeLee group and one in the bulb group. There was no significant difference in the amount of meconium found below the vocal cords, comparing pharyngeal DeLee suction to bulb suction (0.22 cc versus 0.24 cc; p = NS). In conclusion, the data fail to support a significant difference in efficacy between bulb and DeLee suction in clearing the naso- and oropharynx of the neonate of meconium in cephalic-presenting vaginal or cesarean delivery.

Topics: Adult; Amniotic Fluid; Cesarean Section; Female; Humans; Infant, Newborn; Labor Presentation; Meconium; Meconium Aspiration Syndrome; Obstetric Labor Complications; Pharynx; Pregnancy; Prospective Studies; Suction

Topics: Humans; Infant, Newborn; Intubation, Intratracheal; Meconium; Meconium Aspiration Syndrome; Suction

To identify the fetus and newborn at risk for meconium aspiration syndrome the perinatal characteristics of 238 infants delivered through meconium-stained amniotic fluid were prospectively examined. All infants with meconium-stained amniotic fluid were routinely suctioned with a DeLee apparatus before tracheal intubation and suctioning. The type and presence of meconium in the trachea, neonatal breathing before intubation, and Apgar scores were recorded in the delivery room. Intrapartum fetal monitoring data were collected for 80% (190/238) of the mothers and umbilical artery pH for 74% (177/238) of the newborns. Despite suctioning with a DeLee apparatus and endotracheal suctioning, meconium was present in the trachea in 87/238 (37%) and meconium aspiration syndrome developed in 22 (9.2%). A total of 73% of newborns who had meconium aspiration syndrome were delivered through thick meconium. Thick meconium, the presence of fetal tachycardia, and absence of intrapartum fetal cardiac accelerations identified the fetus at high risk for meconium aspiration syndrome. The presence of these monitoring findings and thick meconium should alert obstetricians to the possibility of a fetus that requires intervention. Low umbilical artery pH, Apgar scores less than 5, and meconium in the trachea further characterized the newborn at high risk for meconium aspiration syndrome. The combination of these findings may best identify the infant delivered through meconium-stained amniotic fluid who requires close observation for meconium aspiration syndrome.

Topics: Amniotic Fluid; Apgar Score; Fetal Blood; Fetal Monitoring; Forecasting; Heart Rate; Humans; Hydrogen-Ion Concentration; Infant, Newborn; Intubation, Intratracheal; Meconium; Meconium Aspiration Syndrome; Prospective Studies; Risk Factors; Suction; Trachea; Umbilical Arteries; Viscosity

Immediate suctioning of meconium from the trachea of newborns is believed to be an effective method for preventing or minimizing the meconium aspiration syndrome. Recently, however, the possibility of transmitting disease from the newborn to the physician or vice versa, while using the standard technique of direct oral suction (through a surgical mask), has been stressed. This has prompted the development of alternative methods for suctioning the newborn's trachea. These methods, while eliminating the possibility of disease transmission, create other problems. We, therefore, devised a technique for tracheal suctioning using inexpensive, readily available materials that is not only safe and effective in suctioning meconium but is also practical and easy to perform.

Topics: Humans; Infant, Newborn; Meconium; Meconium Aspiration Syndrome; Suction

Chronically meconium-stained fetuses may ultimately suffer cerebral palsy and other devastation. The mechanism is unknown. Innocuous pregnancy complications may cause some fetuses to discharge meconium, which may become hazardous, independently of aspiration. We herein report previously undescribed, meconium-induced umbilical and placental vascular necrosis. To investigate whether meconium causes vasocontraction, we tested umbilical vein tissue with an isometric transducer connected to a polygraph. The specimens were suspended in a 30-mL organ bath with Krebs solution (pH, 7.4; temperature, 37 degrees C; under aeration with 95% O2 and 5% CO2). We exposed the tissue to meconium and compared meconium-induced vasocontraction with that induced by Krebs solution and 10(-5) molar serotonin. Meconium maximally produced 62.9% of serotonin-induced vasocontraction. Krebs solution and boiled meconium did not produce vasocontraction. We hypothesize that meconium may cause placental and umbilical cord vasocontraction, cerebral and other fetal hypoperfusion, and major poor outcome.

Topics: Asphyxia Neonatorum; Cerebral Palsy; Cerebrovascular Circulation; Female; Humans; Hypoxia, Brain; Infant, Newborn; Ischemia; Meconium; Meconium Aspiration Syndrome; Muscle, Smooth, Vascular; Placenta; Pregnancy; Pregnancy Outcome; Risk Factors; Vasoconstriction

Topics: Humans; Infant, Newborn; Intubation, Intratracheal; Meconium; Meconium Aspiration Syndrome; Nasopharynx; Suction

The aim of the study was to determine the risk of meconium aspiration by perinatal and obstetric characteristics and to give directions for prophylactic management. 67 infants with meconium-stained amniotic fluid received intrapartum pharyngeal suctioning and postpartum direct laryngoscopy and suctioning of the trachea. The risk for the presence of meconium in airways is increased if meconium is visible at the vocal cords (p less than 0.01), amniotic fluid showing thick meconium staining (p less than 0.001) Fischer-score being below 7 points (p less than 0.05) or Apgar-score being below 8 points(p less than 0.05). Immediately after delivery inspection of the vocal cords is necessary by direct laryngoscopy. Suctioning of the trachea under direct vision after delivery should be done if meconium is visualized at the vocal cords. Meticulous care of the fetus exposed to a meconium containing amniotic fluid environment and the avoidance of acute fetal stress may decrease the incidence of meconium aspiration.

Topics: Amniotic Fluid; Female; Humans; Infant, Newborn; Laryngoscopy; Meconium; Meconium Aspiration Syndrome; Pharynx; Pregnancy; Prenatal Diagnosis; Suction

A 1-year prospective survey of obstetric and pediatric management of meconium staining of the amniotic fluid in 464 patients was undertaken. Pharyngeal suctioning before delivery was performed using bulb syringe (N = 130), De Lee suction catheter (N = 186), or both (N = 98); endotracheal intubation after delivery was also done in 413 instances. Using any of the three suctioning techniques, no differences were seen in Apgar scores, respiratory rates, presence or absence of meconium on or below the vocal cords, or development of meconium aspiration syndrome (MAS). If meconium was present on the vocal cords, it was present below the vocal cords in 76% of the cases. If no meconium was visualized, it was found below the vocal cords in only 7% of the cases. Of the 142 infants with meconium below the vocal cords, 10% developed MAS and all 14 survived.

Topics: Amniotic Fluid; Delivery, Obstetric; Female; Humans; Infant, Newborn; Intubation, Intratracheal; Male; Meconium; Meconium Aspiration Syndrome; Prospective Studies; Suction; Syndrome; Vocal Cords

The authors have tried to determine the significance of meconial fluid by studying 3 groups: a first group (MF) representing the meconial fluid observed at he beginning, the second group where the meconial fluid was observed secondarily (SMF) and a third group which is the reference group (RG). The presence of meconial fluid is an ominous sign and an element of prognosis of fetal distress. Meconial fluid at the beginning may be present physiologically, but there are authentic pathological cases with a markedly decreased residual Apgar at 5 minutes. In addition, the perinatal mortality is 4 times higher. In the group with secondary meconial fluid, it is more of an obstetrical emergency. Distress occurs on a healthy fetus along with labor. The signs are occurring with abnormalities of the fetal heart rhythm which do not aggravate the prognosis. These data are confirmed with the study of the pH at the cord. The risk of meconial fluid is inhalation and its complications. The authors conclude by insisting of the need for nasopharyngeal aspirations soon as the fetal head is delivered.

Topics: Adult; Apgar Score; Female; Fetal Distress; Fetal Heart; Heart Rate; Humans; Hydrogen-Ion Concentration; Infant, Newborn; Meconium; Meconium Aspiration Syndrome; Parity; Pregnancy; Pregnancy Complications; Prognosis; Risk Factors

Topics: Amniotic Fluid; Asphyxia Neonatorum; Female; Fetal Distress; Humans; Infant, Newborn; Meconium; Meconium Aspiration Syndrome; Pregnancy