phenylephrine-hydrochloride and Apnea

To determine whether apneic oxygenation through nasal or nasopharyngeal catheters can counteract hypoxemia and desaturation during induction of anesthesia and endotracheal intubation.. Narrative review of randomized controlled trials.. Operating room.. 295 ASA I-II patients in elective surgery.. PubMed and Embase databases were searched for studies with apneic oxygenation. The review included randomized controlled trials with apneic oxygenation through nasal or nasopharyngeal catheters as the intervention in the setting of endotracheal intubation in adults.. Outcome measures were time until desaturation or degree of hypoxemia.. Eight randomized controlled trials were included, with a total of 295 patients. Apneic oxygenation was administered by nasopharyngeal catheter in four studies and by nasal catheter in four studies. The eight included articles studied apneic oxygenation at flow rates of 3-10 l/min in ASA I-II patients undergoing elective anesthesia in the operating room. Apneic oxygenation significantly prolonged time until desaturation opposed to the control groups in seven of the eight studies of patients undergoing anesthesia for elective surgery.. Apneic oxygenation through nasal or nasopharyngeal catheters can prolong time to desaturation and decrease degree of desaturation during induction of anesthesia and endotracheal intubation in adult ASA I-II patients undergoing anesthesia for elective surgery.

Topics: Anesthesia; Apnea; Catheters; Elective Surgical Procedures; Humans; Hypoxia; Intubation, Intratracheal; Nasopharynx; Nose; Operating Rooms; Oxygen Inhalation Therapy; Randomized Controlled Trials as Topic

The nose, as an organ initiating reflexes affecting itself and the rest of the body, and as a target organ of control, is highly complex. Its innervation includes parasympathetic, sympathetic, sensory/afferent, and somatic motor nerves, which combine in a variety of morphologic pathways. The vasculature of the nose contains capacitance vessels such as sinusoids and distensible venules, as well as arteriovenous anastomoses, arterioles, capillaries, and venules. The secretory tissue of the nose includes epithelial cells, submucosal glands, and relatively large anterior or lateral serous glands; in addition, some species have specialized secretory glands. The nose is the source of many powerful reflexes, including the diving response, sneeze and sniff reflexes, and reflexes affecting autonomic nervous function to the cardiovascular system, airways in the lungs, the larynx, and other organs. Axon reflex control of the nasal vasculature is also important. The nasal vasculature can be shown to be under parasympathetic and sympathetic control, but there is little precise information concerning the effect of nerves on different types of blood vessels. Pharmacologic experiments show that vascular resistance and vascular volume can be separately influenced by nerves and mediators, and that vascular resistance and airway resistance are not necessarily inversely related. Nasal secretion is also under the influence of both parasympathetic and sympathetic nerves, and can be induced by a wide range of neurotransmitters and mediators. In general, the concentrations needed to promote secretion are considerably higher than those that affect vascular resistance, at least with regard to the lateral nasal gland of the dog. In humans, nasal patency is affected by several nervous inputs, presumably acting via vascular beds. The nasal cycle is the alternation of resistances between the two sides of the nose, on which other changes are superimposed. In exercise and hyperpnea, nasal airflow resistance decreases, presumably with vascular decongestion. Recent studies of the crutch reflex (the ipsilateral nasal congestion caused by stimulation of the axilla) show that some of the reflex inputs to the nose can be unilateral.

Topics: Airway Resistance; Apnea; Axilla; Diving; Humans; Nasal Mucosa; Nervous System Physiological Phenomena; Nose; Physical Exertion; Pulmonary Ventilation; Reflex; Regional Blood Flow; Respiration Disorders; Sneezing; Thorax

During sedated endoscopic examinations, upper airway obstruction occurs. Nasal breathing often shifts to oral breathing during open mouth esophagogastroduodenoscopy (EGD). High-flow nasal cannula (HFNC) which delivers humidified 100% oxygen at 30 L min

Topics: Adult; Aged; Aged, 80 and over; Apnea; Cannula; Endoscopy; Endoscopy, Digestive System; Female; Humans; Hypnotics and Sedatives; Hypoxia; Male; Mandibular Advancement; Middle Aged; Mouth; Nose; Oxygen; Oxygen Inhalation Therapy

Noninvasive ventilation (NIV) in preterm infants is currently applied using intermittent positive pressure (2 positive-pressure levels) or in a conventional manner (one pressure level). However, there are no studies in the literature comparing the chances of failure of these NIV methods. The aim of this study was to evaluate the occurrence of failure of 2 noninvasive ventilatory support systems in preterm neonates over a period of 48 h.. A randomized, prospective, clinical study was conducted on 80 newborns (gestational age < 37 weeks, birthweight < 2,500 g). The infants were randomized into 2 groups: 40 infants were treated with nasal CPAP and 40 infants with nasal intermittent positive-pressure ventilation (NIPPV). The occurrence of apnea, progression of respiratory distress, nose bleeding, and agitation was defined as ventilation failure. The need for intubation and re-intubation after failure was also observed.. There were no significant differences in birth characteristics between groups. Ventilatory support failure was observed in 25 (62.5%) newborns treated with nasal CPAP and in 12 (30%) newborns treated with NIPPV, indicating an association between NIV failure and the absence of intermittent positive pressure (odds ratio [OR] 1.22, P < .05). Apnea (32.5%) was the main reason for nasal CPAP failure. After failure, 25% (OR 0.33) of the newborns receiving nasal CPAP and 12.5% (OR 0.14) receiving NIPPV required invasive mechanical ventilation.. Ventilatory support failure was significantly more frequent when nasal CPAP was used.

Topics: Apnea; Birth Weight; Continuous Positive Airway Pressure; Disease Progression; Epistaxis; Female; Gestational Age; Humans; Infant, Newborn; Infant, Premature; Intermittent Positive-Pressure Ventilation; Intubation; Male; Noninvasive Ventilation; Nose; Prospective Studies; Respiratory Distress Syndrome, Newborn; Single-Blind Method; Treatment Failure

To determine whether lung volume changes and breathing pattern parameters differ among 3 devices for delivery of nasal continuous positive airway pressure (CPAP) in premature infants.. Thirty-two premature infants receiving nasal CPAP for apnea or mild respiratory distress were enrolled. Birth weight was (mean +/- standard deviation) 1081 +/- 316 g, gestational age 29 +/- 2 weeks, age at study 13 +/- 12 days, and fraction of inspired oxygen (FIO(2)) at study.29 +/-.1. Three devices, applied in random order, were studied in each infant: continuous flow nasal CPAP via CPAP prongs, continuous flow nasal CPAP via modified nasal cannula, and variable flow nasal CPAP. After lung recruitment to standardize volume history, changes in lung volume (DeltaV(L)) were assessed at nasal CPAP of 8, 6, 4, and 0 cm H(2)O using calibrated direct current-coupled respiratory inductance plethysmography.. DeltaV(L) was significantly greater overall with the variable flow device compared with both the nasal cannula and CPAP prongs. However, DeltaV(L) was not different between the cannula and the prongs. Respiratory rate, tidal volume, thoraco-abdominal asynchrony, and FIO(2) were greater with the modified cannula than for either of the other 2 devices.. Compared with 2 continuous flow devices, the variable flow nasal CPAP device leads to greater lung recruitment. Although a nasal cannula is able to recruit lung volume, it does so at the cost of increased respiratory effort and FIO(2).

Topics: Apnea; Humans; Infant, Newborn; Infant, Premature; Infant, Premature, Diseases; Lung Compliance; Nose; Positive-Pressure Respiration; Respiration; Respiratory Insufficiency; Total Lung Capacity

The efficacy of nasal intermittent positive pressure ventilation (NIPPV) in treating apnea of prematurity was evaluated. Apneic preterm infants were randomly assigned to receive either NIPPV or continuous positive airway pressure (NCPAP) for 4 hr when they failed to respond to conservative therapy. The amount of reduction in apneic spells and bradycardia in the two groups after treatment was compared. Thirty-four infants (18 with NIPPV, 16 with NCPAP) were enrolled. Their birth weights ranged from 590-1,880 g (mean, 1,021 g) and gestational ages from 25-32 weeks (mean, 27.6 weeks). The baseline characteristics were comparable in the two groups. Frequency of apnea and bradycardia was reduced during both forms of treatments. However, the infants receiving NIPPV had a greater reduction of apneic spells (P = 0.02) and a tendency to greater decrease in bradycardia (P = 0.09) than those receiving NCPAP. We conclude that NIPPV is more effective than NCPAP in reducing apnea in preterm infants. NIPPV may reduce bradycardia; however, this needs to be validated by a larger number of observations.

Topics: Apnea; Humans; Infant, Newborn; Infant, Premature; Infant, Premature, Diseases; Intermittent Positive-Pressure Ventilation; Nose; Positive-Pressure Respiration; Statistics, Nonparametric

Ventilation using 100% oxygenation creates a risk of fire during laser microlaryngeal surgery (MLS). The purpose of this study is to describe the technique of transnasal high-flow ventilation using laser safe (30%) oxygen conditions, measure the intraoperative real-time laryngeal oxygen concentration, and examine patient saturation status using this technique.. Prospective IRB approved study of patients undergoing tubeless laser MLS using high-flow nasal oxygenation. Delivered oxygen concentration was reduced from 100% to 30% before lasering using an oxygen-air blender then increased to 100% post-laser procedure. Outcome measures included time for laryngeal oxygen concentration to equalize to laser safe levels; time to, methods of and duration of rescue ventilation; and desaturation rates and apnoeic times at both 100% and 30% oxygen deliveries.. Fifty patients were recruited (mean age = 47.4 years). Mean laryngeal oxygen concentration (%) at 100% and 30% deliveries was 98.46 and 31.45, respectively. Mean (SD) of laryngeal oxygen concentration equalization time to 30% (seconds) was 9.4 (3.69). At 30% oxygen delivery desaturation rate was faster and apneic time shorter compared with 100%. Eighteen patients required rescue (jet) ventilation and they had a faster apneic desaturation rate (%/minute) than patients not requiring rescue. Mean (SD) apneic time (minutes) at 30% delivery was 4.56 (2.25) and 4.41 (2.18) in rescue versus non-rescue groups respectively. BMI was the only significant predictor of desaturation rate at 30% oxygen delivery.. It is possible to achieve a safe time window for use of laser during MLS using transnasal humidified high-flow ventilation by delivering 30% oxygen concentration.. 4 Laryngoscope, 133:634-639, 2023.

Topics: Apnea; Humans; Larynx; Laser Therapy; Middle Aged; Nose; Oxygen; Oxygen Inhalation Therapy; Prospective Studies

To investigate the effect and clinical value of simultaneous multiple plane operations in treating severe OSAHS.. The clinical data of 93 patients with severe OSAHS were retrospectively analyzed. According to different obstruction plane, all the patients were performed different multiple planes of operations. Operations were finished in the same term. All patients underwent PSG examination before operation and 6-month, 1 year after surgical treatment separately.. No severe complication occurred. According to the assessment guidelines, the response rate was 100% in 6-month and 91.40% in 1-year respectively.. Most OSAHS have multi-level obstructions in upper airway caliber, such as nasal, nasopharyngeal, velo-pharyngeal and tongue-pharyngeal obstruction. Simultaneous multiple plane operations which based on multiple plane obstruction can improve curative effect.

Topics: Adult; Apnea; Female; Humans; Male; Middle Aged; Nasopharynx; Nose; Otorhinolaryngologic Surgical Procedures; Pharynx; Polysomnography; Retrospective Studies; Sleep Apnea, Obstructive; Tongue

The published AASM guidelines approve use of a nasal cannula/pressure transducer to detect apneas/hypopneas, but require esophageal manometry for Respiratory Effort-Related Arousals (RERAs). However, esophageal manometry may be poorly tolerated by many subjects. We have shown that the shape of the inspiratory flow signal from a nasal cannula identifies flow limitation and elevated upper-airway resistance. This study tests the hypothesis that detection of flow limitation events using the nasal cannula provides a non-invasive means to identify RERAs.. N/A.. 10 UARS/OSAS and 5 normal subjects. All subjects underwent full NPSG. Two scorers identified events from the nasal cannula signal as apneas, hypopneas, and flow limitation events. Two additional scorers identified events from esophageal manometry. Arousals were scored in a separate pass. Interscorer reliability and intersignal agreement were assessed both without and with regard to arousal. The total number of respiratory events identified by the two scorers of the nasal cannula was similar with an Intraclass Correlation (ICC) =0.96, and was essentially identical to the agreement for the two scorers of esophageal manometry (ICC=0.96). There was good agreement between the number of events detected by the two techniques with a slight bias towards the nasal cannula (4.5 events/hr). There was no statistically significant difference (bias 0.9/hr, 95%CI -0.3-2.0) between the number of nasal cannula flow limitation events terminated by arousal and manometry events terminated by arousal (RERAs).. The nasal cannula/pressure transducer provides a non-invasive reproducible detector of all events in sleep disordered breathing; in particular, it detects the same events as esophageal manometry (RERAs).

Topics: Adult; Aged; Apnea; Arousal; Catheterization; Esophagus; Female; Humans; Male; Manometry; Middle Aged; Nose; Pressure; Respiration; Transducers

Apnea in the neonatal period frequently is associated with prematurity. Full-term infants who develop apnea usually have associated clinical conditions such as infection, shock, metabolic disorders, neonatal abstinence syndrome, intracranial pathology, and gastroesophageal reflux. Gastric ulcer also is a rare phenomenon in the neonatal period. We describe a full-term infant presenting with apnea. Upon investigation, a 6-channel pneumocardiogram revealed central apnea and multiple episodes of low esophageal pH (< 4), which is suggestive of gastroesophageal reflux. This was confirmed by an upper gastrointestinal series. A small antral ulcer crater also was demonstrated. When assessing the etiology of apnea in a full-term infant, gastroesophageal reflux and gastric ulcer should be considered.

Topics: Anti-Ulcer Agents; Apnea; Cisapride; Esophagus; Gastroesophageal Reflux; Humans; Hydrogen-Ion Concentration; Infant, Newborn; Male; Nose; Oxygen; Piperidines; Pulmonary Ventilation; Pulse; Ranitidine; Respiration; Stomach Ulcer

In order to determine the feasibility of performing mouth to mouth and nose resuscitation according to the established guidelines, a study was carried out on the facial dimensions of 40 children under 2 months of age (20 under 1 month and 20 aged 1 month) and the open-mouth dimensions of the 40 adults in charge of these children. Only nine adults in charge of children under 1 month of age would have been able to seal the mouth and nose of these infants. In the case of the 1 month old infants, only one adult (5%) proved able to encircle the mouth and nose. Strikingly, none of the adults involved in this study would have been able to perform the ventilation manoeuvres in children with open mouths as recommended by the American Heart Association and European Resuscitation Council guidelines. In conclusion, since adults are unable to cover with their mouths both the mouth and nose of the infants, the nasal route to ventilation, with oral sealing of the nose, is recommended as the best approach for the practice and teaching of the basic cardiopulmonary resuscitation (CPR) in children under 2 months of age who have respiratory arrest.

Topics: Adult; American Heart Association; Apnea; Cardiopulmonary Resuscitation; Cephalometry; Europe; Face; Feasibility Studies; Guidelines as Topic; Humans; Infant; Infant, Newborn; Mouth; Nose; Respiration; Teaching; United States

The purpose of this study was to examine the behavior of the glottis during intermittent positive-pressure ventilation (nIPPV) using a two-level positive-pressure ventilator and to compare the glottic adaptation to this ventilatory mode with the one observed using volumetric ventilators, recently reported by us. Six healthy subjects were studied during both wakefulness and sleep. Their glottis was continuously monitored through a fiberoptic bronchoscope. We measured breath by breath the widest inspiratory angle formed by the vocal cords at the anterior commissure, the corresponding tidal volume, and other indices. We used the controlled ventilatory mode. The expiratory pressure was kept at 4 cm H2O, and the inspiratory pressure was increased by steps from 10 to 15 to 20 cm H2O. Increases in inspiratory pressure did not always lead to increases in effective ventilation reaching the lungs. This was due to a significant narrowing of the glottis by adduction of the vocal cords in all subjects. Periodic breathing with or without apneas were common during wakefulness, but especially during sleep, representing 10.5 +/- 11% (SD) of total sleep time. We conclude that effective ventilation during nIPPV using a two-level positive-pressure ventilator in the controlled mode is less predictable and less stable than during nIPPV using volumetric ventilators.

Topics: Adaptation, Physiological; Adult; Apnea; Bronchoscopes; Equipment Design; Female; Fiber Optic Technology; Glottis; Humans; Inhalation; Intermittent Positive-Pressure Ventilation; Lung; Male; Monitoring, Ambulatory; Nose; Pressure; Pulmonary Ventilation; Respiration; Sleep; Sleep Apnea Syndromes; Tidal Volume; Ventilators, Mechanical; Vocal Cords; Wakefulness

Early treatment with nasal continuous positive airway pressure (CPAP) in newborns with respiratory distress syndrome is useful, by recruiting alveoli and restoring the functional residual capacity.. Nasal CPAP was supplied by the Infant Flow Driver (Electro Medical Equipment). From 15 June 1994 to 15 December 1994, 42 neonates received nasal CPAP. Their mean birthweight and gestational age were 1511 +/- 411 g and 30.9 +/- 2.5 weeks, respectively. Fifteen infants had been ventilated for hyaline membrane disease and nasal CPAP was applied immediately after extubation. In the other 27 infants, nasal CPAP was given soon after birth (respiratory distress syndrome: 20 neonates; apneic spells: seven neonates).. Three infants needed subsequent mechanical ventilation because of the severity of the disease (one had spontaneous pneumothorax); four infants received exogenous surfactant (Curosurf, one single dose) within a brief period of mechanical ventilation (30-45 min). There were no failure of extubation, and no intracranial lesions. Excess of pharyngeal secretion and abdominal distension were common.. Early treatment with nasal CPAP reduces the need for mechanical ventilation. Furthermore, surfactant therapy required by a moderate to severe disease is possible with a rather short period of artificial ventilation.

Topics: Apnea; Birth Weight; Gestational Age; Humans; Infant, Newborn; Infant, Premature; Nose; Positive-Pressure Respiration; Respiratory Distress Syndrome, Newborn

We have previously observed that, in normal awake subjects passively hyperventilated with intermittent positive-pressure ventilation delivered through nasal access (nIPPV), the glottis could interfere with the ventilation. We report on data obtained in the same subjects during stable sleep. In all cases, the glottis was continuously observed through a fiber-optic bronchoscope, and other indexes were also continuously recorded. Mechanical ventilation was progressively increased up to 30 l/min. We have observed during passive nIPPV in stable sleep that increases in delivered minute ventilation (VEd) resulted in progressive narrowing of the glottic aperture, with increases in inspiratory resistance and progressive reductions in the percentage of the delivered tidal volume effectively reaching the lungs. For a given level of VEd, comparisons showed that the glottis was significantly narrower during sleep than during wakefulness and that the glottis was significantly narrower during stage 2 than during stages 3/4 non-rapid-eye-movement sleep. Moreover, when CO2 is added to the inspired air, glottic aperture increased in five of nine trials without changes in sleep stage. We also observed a significant negative correlation between glottic width and the VED, independent of the CO2 level. We conclude that during nIPPV glottis narrowing results in a decrease in the proportion of the delivered tidal volume reaching the lungs.

Topics: Adult; Apnea; Carbon Dioxide; Female; Glottis; Humans; Hypercapnia; Hyperventilation; Male; Nose; Positive-Pressure Respiration; Reference Values; Respiration; Sleep; Sleep Stages; Tidal Volume; Wakefulness

Topics: Animals; Apnea; Diving; Heart Rate; Immersion; Nose; Skin; Swine

Snoring is a common disorder usually presenting to otolaryngologists. Most patients who have any nasal symptoms would normally be offered nasal surgery, but there is a significant incidence of failure to control the snoring (approximately 25%). We analysed a group of patients, all having nasal surgery for snoring, with the aim of assessing whether any pre-operative factors would predict success or failure of the surgery. We found symptoms of excessively loud snoring, witnessed apnoeic episodes and hypersomnolence, or obstructive sleep apnoea diagnosed by overnight oxygen saturation measurements to be statistically associated with failure of nasal surgery to improve snoring.

Topics: Adult; Aged; Airway Resistance; Apnea; Endoscopy; Female; Fiber Optic Technology; Humans; Male; Middle Aged; Nasal Obstruction; Nose; Polysomnography; Sleep Apnea Syndromes; Sleep Stages; Snoring; Sound; Treatment Failure; Treatment Outcome

The prevalence of preferential nasal breathing was studied in an awake adult population. One hundred and ninety-four people consented to gentle manual compression of the nostrils. They were advised to 'breathe in and out', but no further information regarding breathing was given to avoid influencing the patient. One hundred and eighty patients (92.8%) commenced immediate regular relaxed breathing. Fourteen patients (7.2%) had difficulty with oral breathing which ranged from irregular mouth breathing associated with distress to no spontaneous respiration. The prevalence of preferential nasal breathing was strongly associated with increasing age (chi 2 for trend, P = 0.007). In addition, a weakly significant association was demonstrated between a history of asthma and this phenomenon (P = 0.047). These findings suggest a tendency for the elderly person to revert to the infant pattern of obligate nasal breathing. Physicians should be aware of this possibility in the elderly patient, especially prior to any procedure which may induce nasal obstruction.

Topics: Adolescent; Adult; Age Factors; Aged; Aged, 80 and over; Apnea; Asphyxia; Asthma; Female; Humans; Male; Middle Aged; Mouth; Mouth Breathing; Nasal Obstruction; Nose; Prevalence; Respiration

Twenty four preterm infants (median birth weight 1120 g and gestation 29 weeks) were studied on 83 occasions by measuring upper airway airflow. Airway patency was detected by the transmission of cardiac impulse up the airway and airway closure by its absence. A total of 309 apnoeas of at least five seconds' duration were recorded. One hundred and eighty (58.0%) were central, 109 (35.5%) mixed, and 20 (6.5%) obstructive. Airway closure was noted in 47% of apparently central apnoeas. Airway closure occurred as apnoea lengthened; the airway remained patent in 38% of apnoeas of 5-9 seconds, 17% of those 10-14 seconds, and 11% of those 15-19 seconds' duration. Airway closure occurred in every apnoea of greater than or equal to 20 seconds. As a consequence, closed apnoeas were longer than open apnoeas (mean 9.7 v 6.6 seconds). In 72% of mixed apnoeas, airway closure was recorded during the central element and this usually preceded obstructive breaths. In 20% of mixed apnoeas and 15.5% of the total group the airways closed, having previously been patent. This occurred after a mean of 3.5 seconds (range 1-17). Mixed apnoea produced a significantly greater drop in arterial oxygen saturation than central apnoea, but only because of the greater duration of mixed apnoea. Airway closure occurs in both central and mixed apnoea and appears to be important in the pathophysiology of mixed apnoea. Central and mixed apnoea are part of a continuum of airway closure and not separate entities.

Topics: Apnea; Electrocardiography; Humans; Infant, Newborn; Infant, Premature; Larynx; Nose; Oxygen; Pulmonary Ventilation; Time Factors

Impedance pneumography in combination with expired CO2 monitoring are commonly used techniques for detecting central and obstructive apnea in infants. In this investigation an American Telephone and Telegraph StarSet-1 3000-ohm self-actuating microphone connected to the end of an infant cannula was used to monitor neonatal nasal airflow to detect breaths and apnea. The microphone was placed in a soundproof container to eliminate environmental sound artifacts. Analyses of 100 breaths from five patient samples during active and quiet sleep showed that there was no significant difference between microphone and expired CO2 recording of respiration. The techniques were 98% and 96% sensitive, respectively. Microphonic detection of nasal airflow identified 27 of the 32 episodes of upper airway obstruction (84.2%) registered by end-tidal CO2 recording. Inspiratory and expiratory events could also be well documented. Microphonic recording of nasal airflow is a reliable and inexpensive technique to detect apnea.

Topics: Apnea; Breath Tests; Carbon Dioxide; Electronics, Medical; Humans; Infant, Newborn; Monitoring, Physiologic; Nose; Pulmonary Ventilation; Respiration

Brief end-expiratory airway occlusions were performed in 22 preterm babies, 17 with and 5 without clinical apnea, and 4 full-term babies, 1 with Pierre-Robin syndrome. Airway stability was evaluated by comparing pressures measured simultaneously in the chest and nasal passages during occluded inspiratory efforts. The airway remained patent throughout all 301 trials in 20 babies during rapid-eye-movement (REM) and quiet sleep. Airway closure occurred during 31/102 trials in 6 babies (5 preterm and 1 term with Pierre-Robin syndrome), more commonly in quiet than in REM sleep. Overall and within individuals, mean closing pressures were significantly lower than the mean maximum falls in airway pressure recorded during occlusions without closure. Mixed-obstructive and obstructive apnea was significantly more frequent in babies with airway closure than in those without (5.3 +/- 4.0 vs. 0.4 +/- 0.8 episodes/h). Pauses in breathing greater than or equal to 3 s occurred during 28% of occlusions in preterm infants and 2% of occlusions in full-term babies. There was no significant difference between the mean frequency of pauses during occlusion and during the preceding control period or in the incidence of pauses in occlusions with vs. those without closure. It is concluded that the airway of most preterm and full-term babies is remarkably stable under load. Intermittent closure occurs in certain infants and may be related to airway muscle dysfunction.

Topics: Airway Obstruction; Apnea; Female; Humans; Infant; Infant, Newborn; Male; Nose; Respiration; Sleep, REM

To determine whether regurgitation might be a factor in the pathogenesis of apnea in certain infants, we compared the frequency of short and prolonged apnea immediately following regurgitation to that during control periods. Ten infants (nine preterm and one term) with histories of frequent regurgitation and also apneic spells were studied for 2 to 3 hours by monitoring nasal airflow, abdominal respiratory movements, electrocardiogram, pharyngeal pH, and pharyngeal pressure. In six of these infants additional observations were made without the intrapharyngeal recording devices. Fourty-four episodes of regurgitation were observed. Both prolonged apnea (P less than 0.05) and short apnea (P less than 0.01) occurred much more frequently during regurgitation than during the control period; however, the majority of prolonged apneic spells observed were unassociated with regurgitation. The increased frequency of apnea during regurgitation was not related to the presence of intrapharyngeal recording devices. Although nasal regurgitation was frequently associated with short apnea, no prolonged apnea was observed during the seven episodes of nasal regurgitation observed. The 14-fold increase in prolonged apnea frequency immediately following regurgitation supports the hypothesis for a causal relationship between apnea and regurgitation.

Topics: Apnea; Gastroesophageal Reflux; Humans; Infant, Newborn; Infant, Newborn, Diseases; Infant, Premature; Monitoring, Physiologic; Nose; Pulmonary Ventilation; Time Factors

Eight children with obstructive apnea were evaluated by transnasal fiberoptic endoscopy. Three children had obstructive adenoids and tonsils, 2 had pharyngeal collapse, 1 had an obstructive tongue, and 1 had a subglottic cyst. The remaining patient had no abnormality. The results of transnasal endoscopy influenced therapeutic interventions.

Topics: Airway Obstruction; Apnea; Child, Preschool; Endoscopy; Female; Fiber Optic Technology; Humans; Infant; Male; Nose; Pharyngeal Diseases

Topics: Apnea; Bradycardia; Humans; Infant, Newborn; Infant, Premature; Infant, Premature, Diseases; Mouth; Nose; Suction

Respiratory distress, apnea, and chronic pulmonary disease since birth were identified in 14 infants who also had symptomatic gastroesophageal reflux. Birth weights varied from 760 to 4,540 gm. All infants had radiographic changes similar to those in bronchopulmonary dysplasia. Cessation of apnea and improvement of pulmonary disease occurred only after medical (8) or surgical (6) control of gastroesophageal reflux. Simultaneous tracings of esophageal pH, heart rate, impedance pneumography, and nasal air flow in five infants demonstrated that reflux preceded apnea. Apnea could be induced by instillation of dilute acid, but not water or formula, into the esophagus. Prolonged monitoring of esophageal pH more than two hours after feeding in 14 other infants less than 6 weeks of age (birth weight 780 to 3,350 gm) without a history of recent vomiting indicated that reflux was not greater than in normal older children.

Topics: Apnea; Chronic Disease; Gastroesophageal Reflux; Heart Rate; Humans; Hydrogen-Ion Concentration; Infant, Newborn; Infant, Newborn, Diseases; Lung Diseases; Nose; Pneumonia, Aspiration; Pulmonary Ventilation; Respiratory Distress Syndrome, Newborn

The philtrum point VG 26 (Jen Chung) was needled in 69 cases of respiratory depression or apnoea in dogs and cats during induction or maintenance of general anaesthesia. Respiration was restored to normal or near normal rates within 10 to 30 seconds of insertion of the needle in all the cases. In seven cases of anaesthetic apnoea with concurrent cardiac arrest and absence of vital signs, the revival rate was 43 per cent. Those which recovered required four to 10 minutes of acupuncture stimulation. In eight cases of collapse due to other causes, the revival rate was 25 per cent. The cases included five sheep in shock following liver biopsy, two cases of haemorrhagic shock (dog, cat) and one terminal collapse in chronic congestive heart failure (dog).

Topics: Acupuncture Therapy; Anesthesia, General; Animals; Apnea; Cat Diseases; Cats; Dog Diseases; Dogs; Heart Arrest; Nose; Respiratory Insufficiency; Sheep; Sheep Diseases

The nasal CPAP modification of spontaneous positive pressure breathing is technically simple, non-invasive for the patient, and does not interfere with routine infant care, yet provides most of the advantages of other CPAP modifications. Endotracheal intubation is eliminated since airway pressure is delivered by two short canules attached by means of adhesive tape to the patient's nose. The CPAP system was used in the care of 35 newborns and premature infants admitted to the University Children's Clinic Graz, with the diagnosis of respiratory distress (31 cases) or apnea-syndrome (4 cases) between Sept. 1973 and July 1975. The indications for the use of this system was based on the arterial oxygen tension values while breathing 100% O2 for 15 min. 22 of the 28 patients surviving were treated with N-CPAP alone, whereas 13 patients were CPAP-failures and required further ventilation (IPPV,PEEP). In the latter group apnea and 2 cases of pneumothorax necessitated intubation and ventilation, rather than the respiratory distress for which they had been initially treated. All 7 patients who died during this study were from this group of N-CPAP-failures (20% of the total, 54% of all N-CPAP-failures). Keeping ambient oxygen concentrations constant, an increase in arterial oxygen tension was measured in almost all patients surviving on N-CPAP and was initially even seen in those who later died, so that the ambient oxygen concentration could eventually be decreased.

Topics: Apnea; Blood Gas Analysis; Humans; Infant, Newborn; Nose; Oxygen; Partial Pressure; Positive-Pressure Respiration; Respiratory Distress Syndrome, Newborn

Ten newborn infants with the idiopathic respiratory distress syndrome (IRDS) or foetal aspiration (FA) were treated with a simplified nasal CPAP system (continuous positive airway pressure). The system consists of a Hudson binasal cannula and a Benveniste pediatric jet device (weight 5 g). The desired airway pressures are obtained by adjustment of the jet flow in accordance with the naso-pharyngeal flow/pressure relationship. The system was found to be effective in the treatment of 9 of the 10 children, as demonstrated by improved blood gas values, and improved respiration; the latter was also evident in infants with pronounced apnea. In one child pneumothorax, occuring after about 24 hours of successful CPAP treatment, necessitated respirator treatment. The system is quick and simple to use, and permits feeding, lung physiotherapy and routine nursing of the child during treatment.

Topics: Apnea; Female; Humans; Infant, Newborn; Infant, Newborn, Diseases; Male; Nose; Pneumothorax; Positive-Pressure Respiration; Prospective Studies; Respiratory Distress Syndrome, Newborn

Topics: Apnea; Eye Protective Devices; Humans; Infant, Newborn; Male; Nose; Protective Devices

1. Diving apnoea in Rana pipiens was initiated by submerging the external nares. As the water level was raised above the frog, both buccal and lung pressure increased by an amount corresponding to the water head. During submergence the external nares remained closed, although the apnoeic period was punctuated by ventilation movements which moved gas between the lungs and buccal cavity. 2. Bilateral section of the ophthalmic nerves did not alter the normal pattern of ventilation in air, although it often resulted in the intake of water into the buccal cavity on submergence. Introduction of water into the buccal cavity, either naturally as in denervates or by injection through a catheter in intact frogs, triggered sustained electromyographical activity in some respiratory muscles. 3. Electroneurograms recorded from the cut peripheral end of an ophthalmic nerve showed that receptors in the external narial region were stimulated by movement of a water meniscus across them. Activity could also be recorded in the ophthalmic nerve in response to water flow past the submerged nares. Punctate stimulation of the narial region confirmed that these receptors were mechanosensitive. 4. Bilateral electrical stimulation of the central ends of cut ophthalmic nerves in lightly anaesthetized frogs caused apnoea with a latency of less than 200 ms. The external nares remained closed throughout the period of stimulation although buccal pressure events, resembling underwater ventilation movements, occurred when stimulation was prolonged.

Topics: Action Potentials; Air Pressure; Animals; Apnea; Diving; Electric Stimulation; Lung; Neurons; Nose; Rana pipiens

Topics: Airway Obstruction; Apnea; Death, Sudden; Humans; Infant; Infant, Newborn; Nose; Reflex; Respiration; Sleep, REM

Topics: Animals; Apnea; Atropine; Cardiovascular System; Glottis; Neurons, Afferent; Nose; Rabbits; Reflex; Respiratory System; Rest; Stimulation, Chemical; Vagotomy; Vagus Nerve

Topics: Apnea; Asphyxia Neonatorum; Death, Sudden; Female; Humans; Infant, Newborn; Labor Presentation; Nose; Pregnancy; Reflex

Topics: Apnea; Asphyxia; Death, Sudden; Female; Humans; Infant; Infant, Newborn; Infant, Newborn, Diseases; Male; Nose; Respiration; Respiratory Insufficiency; Seasons