Use of Sevoflurane During Elective Cesarean Birth

Effects of Propofol versus Sevoflurane on Postoperative Pain and Neuroendocrine Stress Response in Oocyte Pickup Patients

Background

Pain aggravates the autonomic response to stress and raises neuroendocrine stress hormone levels. We compared the effects of propofol and sevoflurane on postoperative pain and neuroendocrine stress hormones. A prospective, randomized, and controlled trial was conducted with 60 patients.

Methods

We randomly allocated patients to groups P (remifentanil/propofol, n = 30) and S (remifentanil/sevoflurane, n = 30). Preoperative blood samples were taken to measure serum adrenocorticotropic hormone (ACTH), corticotropin-releasing hormone (CRH), glucagon, cortisol, aldosterone, and prostaglandin E2 (PGE2) levels. Intraoperatively and postoperatively, clinical parameters were monitored at different time points. The hormone levels were again measured in the follicular fluid and blood postoperatively.

Result

Demographic data were similar. The preoperative serum aldosterone levels were significantly higher in group P (p=0.001). Preoperative and postoperative serum ACTH, glucagon, cortisol, and PGE2 levels were significantly different in group P (p=0.009, p=0.004, p=0.029, and p=0.002); serum ACTH, glucagon, and PGE2 levels increased while serum cortisol levels decreased postoperatively. In group S, serum CRH and aldosterone levels, both increased in the postoperative period compared to the preoperative (p=0.001, p=0.006). Postoperatively, glucagon and PGE2 levels were both higher in group P than group S (p=0.019, p=0.015). In postoperative follicular fluid, glucagon and PGE2 levels were higher in group P, while cortisol levels were higher in group S (p=0.001, p=0.007, and p=0.001).

Conclusion

The effects of anesthetic agents were different. In group P, in the preoperative and postoperative evaluation, ACTH, glucagon, and PGE2 increased postoperatively, while cortisol decreased. In group S, aldosterone and CRH increased postoperatively. Glucagon and PG E2 were higher in group P than S, postoperatively.

Anesthésie maternofœtale pour « ex utero intrapartum » traitement (EXIT) procédure : à propos de deux cas

The ex utero intrapartum treatment (EXIT) procedure is a surgical procedure maintaining utero-placental circulation during caesarean section. Anaesthetic implications are described: foetal transplacental anaesthesia to avoid first breathing and to permit surgical procedure on obstructed foetal airway, deep maternal haemodynamically stable anaesthesia to relax uterine smooth muscle during a long caesarean procedure but avoiding post-partum haemorrhage. Volatile anaesthesia with sevoflurane seems to be adequate for these aims. Two cases are described.

The direct depressant effects of desflurane and sevoflurane on spontaneous contractions of isolated gravid rat myometrium

Our purpose was to investigate the direct depressant effects of desflurane and sevoflurane at 0.5, 1 and 2 minimum alveolar concentrations (MAC) on spontaneous contractions of isolated gravid rat myometrium. Ten gravid, albino Wistar rats, weighing 240-310 g and at 19-20 days' gestation were used. Sixty myometrial strips were obtained from 10 rats, and randomly assigned into six groups of 10. After obtaining spontaneous myometrial contractions in de Jalon solution for 45 min, 0.5, 1 or 2 MAC of desflurane or sevoflurane were continuously bubbled in the bath for 15 min and myometrial contractions evaluated during the last 10 min. Desflurane 0.5 MAC did not affect duration or amplitude of spontaneous contractions, but frequency was significantly decreased (P < 0.05). Duration, amplitude and frequency were all significantly decreased by desflurane 1 and 2 MAC (P < 0.05). Sevoflurane did not affect duration, amplitude or frequency at 0.5 MAC, but amplitude and frequency were significantly decreased at 1 MAC and all were significantly decreased at 2 MAC (P < 0.05). The frequency of contractions was decreased 21.2% with 1 MAC desflurane versus 17.1% with 1 MAC sevoflurane. The amplitude and frequency of contractions were decreased 48.2% and 48.7% with 2 MAC desflurane versus 58.9% and 49.3% with 2 MAC sevoflurane, respectively. We suggest that due to tocolytic activity, desflurane and sevoflurane can be useful in non-obstetric surgery during pregnancy.

Effects of maternal anesthesia in the neonate

All commonly used anesthetic agents and drugs undergo placental transfer. Understanding the placental transfer of anesthetic drugs and their effects on the neonate is essential for optimal administration of both regional and general anesthesia. Regional anesthesia is decidedly safer for the mother and, when properly performed, actually may be beneficial to the stressed neonate. The healthy neonate also benefits from maternal analgesia during labor and delivery. General anesthesia may result in transient neonatal depression, particularly when delivery is of an emergency nature. The skill and knowledge of the anesthesiologist are more important than the type of anesthesia administered. Therefore, when properly performed, both regional and general anesthesia are quite safe in terms of neonatal outcome.

[Sevoflurane]

Sevoflurane, a methylethylether halogenated solely with fluorine, is characterized by a low blood/gas solubility (blood/gas partition coefficient = 0.65). This feature allows in a more rapid uptake and elimination than with more soluble agents. MAC is about 2 vol% in young adults and 2.5 vol% in children of more than 6 months of age. It undergoes degradation by soda lime in various components. Among them, compound A (an olefin) produces renal toxicity in rats. Total sevoflurane metabolism represents about 5% of inhaled dose and produces inorganic fluorides. However no renal toxic effects has been reported up to now in animals and in patients. The effects on central nervous and cardiovascular systems are close to those of isoflurane. It decreases cerebral vascular resistances and cerebral oxygen consumption, but does not cause convulsive activity. It decreases myocardial contractility, systolic arterial pressure and systemic vascular resistances, but heart rate remains basically unchanged up to 1 MAC. It does not sensitize the myocardium to catecholamines. It depresses ventilation in a dose-dependent fashion, this effect being more pronounced than that of halothane but less than that of both isoflurane and enflurane. It is not irritant for the airways and has some bronchodilatory effect. In adults, recovery is more rapid than with isoflurane. In children, sevoflurane seems a promising agent owing to its good acceptance for mask induction, as well as its favourable haemodynamic profile. However due to its rapid elimination, analgesic drugs should be administered early enough to decrease the incidence of postoperative pain.