piperidines and Pre-Eclampsia

The spinal anaesthesia, epidural anaesthesia or combinations of these techniques (combined spinal epidural anaesthesia) so far remain the gold standard to facilitate caesarean section. For some reasons such as refusal by the patients, medical reasons or emergency caesarean section, a general anaesthesia can be necessary. In patients with preeclampsia hypertension during endotracheal intubation has to be avoided. Here the application of an opioid is possible or even necessary to lessen increases of the heart rate and blood pressure. To lessen cardiovascular response, short acting Remifentanil has advantages, e.g. the fast clearance rate in newborns. However, the risk for the newborn from respiratory depression has to be considered and experienced staff to care for the newborn should be present after childbirth. Therefore, an interdisciplinary approach seems to be vital to cope with adverse effects that may arise due to the more frequent use of opioids in conjunction with general anaesthesia for caesarean section.

Topics: Adult; Analgesics, Opioid; Anesthesia, Epidural; Anesthesia, General; Anesthesia, Obstetrical; Anesthesia, Spinal; Anesthetics, Dissociative; Cesarean Section; Female; Humans; Infant, Newborn; Ketamine; Piperidines; Pre-Eclampsia; Pregnancy; Remifentanil

Remifentanil is known to attenuate the cardiovascular responses to tracheal intubation. We determined effective doses (ED(50)/ED(95)) of remifentanil to prevent the pressor response to tracheal intubation in patients with severe preeclampsia.. Seventy-five women with severe preeclampsia were randomly allocated to one of five remifentanil dose groups (0.25, 0.50, 0.75, 1.0, or 1.25 μg/kg) given before induction of anaesthesia using thiopental 5 mg/kg and suxamethonium 1.5 mg/kg. Systolic arterial pressure, heart rate and plasma catecholamine concentrations were measured. Neonatal effects were assessed by Apgar scores and umbilical cord blood gas analysis. A dose was considered effective when systolic arterial pressure did not exceed 160 mmHg for more than 1 min following tracheal intubation.. Baseline systolic blood pressure and heart rate did not differ among the groups. The intubation-induced increases of heart rate and blood pressure were attenuated in a dose-dependent manner by remifentanil. ED(50) and ED(95) were 0.59 (95% CI 0.47-0.70) μg/kg and 1.34 (1.04-2.19)μg/kg, respectively. Norepinephrine concentrations remained unaltered following intubation but increased significantly at delivery, with no differences between the groups. Apgar scores and umbilical arterial and venous pH and blood gas values were comparable among the groups. Two women each in the 1.0 and 1.25 μg/kg groups received ephedrine for hypotension defined as systolic arterial pressure <90 mmHg.. The ED(95) of remifentanil for attenuating the hypertensive response to tracheal intubation during induction of anaesthesia in severely preeclamptic patients undergoing caesarean delivery under general anaesthesia was 1.34 μg/kg.

Topics: Adult; Analgesics, Opioid; Anesthesia, General; Anesthetics, Intravenous; Blood Pressure; Cesarean Section; Dose-Response Relationship, Drug; Female; Humans; Hypertension; Intubation, Intratracheal; Laryngoscopy; Middle Aged; Neuromuscular Depolarizing Agents; Piperidines; Pre-Eclampsia; Pregnancy; Remifentanil; Severity of Illness Index; Succinylcholine; Thiopental; Young Adult

The optimal dose of remifentanil to attenuate the cardiovascular responses to tracheal intubation in pre-eclamptic patients undergoing Caesarean delivery under general anaesthesia has not been established. We compared the effects of two low doses of remifentanil on the cardiovascular responses to tracheal intubation and neonatal outcomes.. Forty-eight women with severe pre-eclampsia were randomly assigned to receive either remifentanil 0.5 µg kg⁻¹ (R0.5 group, n=24) or 1 µg kg⁻¹ (R1.0 group, n=24) over 30 s before induction of anaesthesia using thiopental 5 mg kg⁻¹ and succinylcholine 1.5 mg kg⁻¹. Systolic arterial pressure (SAP), heart rate (HR), and plasma catecholamine concentrations were measured. Neonatal effects were assessed using Apgar scores and umbilical cord blood gas analysis.. SAP was decreased by induction of anaesthesia and increased by tracheal intubation in both groups. The peak SAP after intubation was greater in the R0.5 group than in the R1.0 group, whereas it did not exceed baseline values in either group. HR increased significantly above baseline in both groups with no significant differences between the groups. Three subjects in the R1.0 group received ephedrine due to hypotension (SAP < 90 mm Hg). Norepinephrine concentrations remained unaltered after intubation and increased significantly at delivery with no significant differences between the groups. Neonatal Apgar scores and umbilical arterial and venous pH and blood gas values were comparable between the groups.. Both doses of remifentanil effectively attenuated haemodynamic responses to tracheal intubation with transient neonatal respiratory depression in pre-eclamptic patients undergoing Caesarean delivery under general anaesthesia. The 1.0 µg kg⁻¹ dose was associated with hypotension in three of 24 subjects.

Topics: Adult; Analgesics, Opioid; Anesthesia, General; Anesthesia, Obstetrical; Blood Pressure; Cesarean Section; Dose-Response Relationship, Drug; Epinephrine; Female; Heart Rate; Humans; Intubation, Intratracheal; Laryngoscopy; Norepinephrine; Piperidines; Pre-Eclampsia; Pregnancy; Pregnancy Outcome; Remifentanil; Young Adult

We examined the effects of remifentanil on cardiovascular and bispectral index (BIS) responses to tracheal intubation and neonatal outcomes in pre-eclamptic patients undergoing Caesarean delivery under general anaesthesia.. Forty-two women with severe pre-eclampsia were randomly assigned to receive either remifentanil 1 microg kg(-1) (n=21) or saline (n=21) over 30 s before induction of anaesthesia using thiopentone 4 mg kg(-1) and suxamethonium 1.5 mg kg(-1). Mean arterial pressure (MAP), heart rate (HR) and BIS values as well as plasma catecholamine concentrations were measured. Neonatal effects were assessed using Apgar scores and umbilical cord blood gas analysis.. Induction with thiopentone caused a reduction in MAP and BIS in both remifentanil and control groups. Following the tracheal intubation MAP and HR increased in both groups, the magnitude of which was lower in the remifentanil group. BIS values also increased, of which magnitude did not differ between the groups. Norepinephrine concentrations increased significantly following the intubation in the control, while remained unaltered in the remifentanil group. The neonatal Apgar scores at 1 min were significantly lower in the remifentanil group than in the control. However, Apgar scores at 5 min, and umbilical artery and vein blood gas values were similar between the groups.. These results suggest that a single bolus of 1 microg kg(-1) remifentanil effectively attenuates haemodynamic but not BIS responses to tracheal intubation in pre-eclamptic patients undergoing Caesarean delivery under general anaesthesia. However, its use was associated with maternal hypotension and neonatal respiratory depression requiring resuscitation.

Topics: Adult; Analgesics, Opioid; Anesthesia, General; Anesthesia, Obstetrical; Apgar Score; Blood Pressure; Cesarean Section; Electroencephalography; Epinephrine; Female; Heart Rate; Humans; Intubation, Intratracheal; Monitoring, Intraoperative; Norepinephrine; Piperidines; Pre-Eclampsia; Pregnancy; Pregnancy Outcome; Remifentanil; Thiopental

Thirty postpartum preeclamptic patients from the University of South Florida Obstetrical Service were enrolled in a placebo-controlled, randomized, double-blind study to test the effectiveness of ketanserin in lowering the blood pressure. An intravenous bolus of ketanserin resulted in a significant drop in the mean arterial blood pressure. The decrease in the blood pressure could be maintained by a continuous infusion of ketanserin. Hypertension returned after the medication was discontinued. These observations suggest that ketanserin, a selective blocker of type II serotonin receptors, may be effective in acutely reducing elevated postpartum blood pressure in preeclamptic patients, and that serotonin may play a role in the pathogenesis of preeclampsia, but not be important as a mediator in the severity of the disease.

Topics: Adult; Blood Pressure; Double-Blind Method; Female; Humans; Ketanserin; Piperidines; Pre-Eclampsia; Pregnancy; Puerperal Disorders; Random Allocation; Serotonin Antagonists; Time Factors

We investigated the effect of peripheral serotonin receptor blockade on preeclamptic hypertension in 20 postpartum patients by the use of ketanserin, a serotonin receptor antagonist. In a study consisting of a double-blind crossover with placebo, parenteral ketanserin significantly reduced blood pressure from 167/105 to 126/71 mm Hg compared to a decline from 157/98 to 150/91 mm Hg for the placebo (p less than 0.001). All patients became hypertensive again following infusion, although no abrupt rebound in pressure occurred. Side effects were minimal. The results demonstrate that preeclamptic hypertension can be controlled by ketanserin and suggest that serotonin may have a role in the modulation of preeclampsia.

Topics: Adult; Antihypertensive Agents; Blood Pressure; Clinical Trials as Topic; Double-Blind Method; Female; Humans; Hypertension; Infusions, Parenteral; Ketanserin; Piperidines; Pre-Eclampsia; Pregnancy; Random Allocation; Serotonin Antagonists

Topics: Ambulatory Care; Amides; Clopamide; Diuretics; Ergotamine; Female; Humans; Piperidines; Pre-Eclampsia; Pregnancy; Reserpine

Topics: Amides; Clinical Trials as Topic; Clopamide; Diuretics; Female; Humans; Piperidines; Pre-Eclampsia; Pregnancy

Topics: Analgesics, Opioid; Cesarean Section; Female; Humans; Intubation, Intratracheal; Piperidines; Pre-Eclampsia; Pregnancy

A 34-h remifentanil infusion was administered for labor analgesia in a patient with thrombocytopenia and renal insufficiency. Compared with other opioids, remifentanil may produce fewer cumulative effects during prolonged infusion because of its unique metabolism.

Topics: Analgesia, Obstetrical; Analgesics, Opioid; Antiphospholipid Syndrome; Female; Fetus; Humans; Infant, Newborn; Infusions, Intravenous; Male; Pain Measurement; Piperidines; Pre-Eclampsia; Pregnancy; Pregnancy Complications; Remifentanil; Renal Insufficiency; Thrombocytopenia

We describe the use of remifentanil in a woman with severe pre-eclampsia who presented for emergency caesarean section. Remifentanil was effective in obtunding the hypertensive response to laryngoscopy and intubation. Previous studies have found no significant adverse effects of remifentanil on the neonate. With its short duration of action, the use of this new opioid has several potential advantages in the above setting. Further studies are required to explore the use of remifentanil as an adjunct to obstetric general anaesthesia.

Topics: Adult; Analgesics, Opioid; Anesthesia, General; Anesthesia, Obstetrical; Cesarean Section; Emergencies; Female; Humans; Hypertension; Intubation, Intratracheal; Liver; Piperidines; Pre-Eclampsia; Pregnancy; Pregnancy Complications; Remifentanil; Thrombocytopenia

Hypertensive pregnant rats with inhibition of NO synthase are frequently considered as model of pre-eclampsia with proteinuria, hypertension and elevated endothelin (ET-1) blood levels. We describe here the cardiovascular in vivo effects of ET-1 in this rat model since ET-1 and NO are both important vasoactive mediators in uteroplacental circulation. From day 13 of gestation 2 groups of Wistar female rats were fed control (C) or nitroarginine enriched diet (0.063%, Treated: T). On gestational day 20 mean arterial pressure (MAP, mmHg) was measured via a carotid catheter in pentobarbital (60 mg/kg) anesthetized rats. After chronic NO synthase inhibition hypertension develops; MAP on day 20: 158 +/- 2.2 in T and 113 +/- 2.2 in C, p < 0.001. ET-1 bolus injection (0.1 nmol/kg) is rapidly followed by a decrease in blood pressure significantly more important in T: -46 +/- 5.1 than in C: -30 +/- 2.2. In vivo depressor effect is blocked by the specific antagonist BQ-788. After inhibition of cycloxygenase with acetylsalicylic acid (27 mumol/kg, 30 min before) the hypotension is not modified. Since NO and PGI2 productions are not expected in our conditions, vasodepressor effect can be explained by an endothelial hyperpolarazing factor (EDHF). In conclusion in vivo ET-1 hypotensive effects in pregnant rats are mediated by ETB receptors and more pronounced in hypertensive NO-deprived animals.

Topics: Animals; Disease Models, Animal; Endothelin Receptor Antagonists; Endothelin-1; Female; Hypotension; Nitric Oxide Synthase; Oligopeptides; Piperidines; Pre-Eclampsia; Pregnancy; Pregnancy, Animal; Rats; Rats, Wistar

Ketanserin was administered intravenously as either 20 or 10 mg boluses to 16 patients with severe preeclampsia in labor. The fetal heart rate was monitored with a scalp electrode and the uterine contractions were evaluated with a fluid-filled catheter connected to a physiologic pressure transducer. A 10-minute recording before every administration of ketanserin was compared to the same period immediately afterward. Ketanserin lowered the systolic and diastolic blood pressure significantly (p less than 0.005, paired Student's t test). Maternal heart rate was unchanged but the mean fetal heart rate increased by 4.6 bpm. Long-term beat-to-beat variability and acceleration patterns were not affected. On four occasions an improvement in variable decelerations of the fetal heart, due to a reduction in uterine activity, was seen. Changes in the amplitude of contractions were not statistically significant. The frequency of contractions, however, was significantly reduced from 3.6 to 2.4 per 10 minutes (p less than 0.005). No serious adverse effects occurred.

Topics: Blood Pressure; Female; Fetal Heart; Heart Rate; Humans; Hypertension; Ketanserin; Obstetric Labor Complications; Piperidines; Pre-Eclampsia; Pregnancy; Uterine Contraction

Topics: Adult; Antihypertensive Agents; Delivery, Obstetric; Female; Humans; Hydralazine; Hypertension; Infant, Newborn; Ketanserin; Piperidines; Pre-Eclampsia; Pregnancy; Serotonin Antagonists; Time Factors; Vascular Resistance

Topics: Amides; Blood Pressure; Chlorine; Clopamide; Creatinine; Delivery, Obstetric; Diuretics; Drug Combinations; Ergoloid Mesylates; Female; Humans; Infant, Newborn; Piperidines; Potassium; Pre-Eclampsia; Pregnancy; Reserpine; Sodium; Uric Acid

Topics: Adult; Antihypertensive Agents; Blood Pressure; Female; Ganglionic Blockers; Humans; Natural Childbirth; Piperidines; Pre-Eclampsia; Pregnancy

Topics: Amides; Clopamide; Diuretics; Edema; Female; Humans; Piperidines; Pre-Eclampsia; Pregnancy