Desflurane: a new volatile anesthetic for cesarean section. Maternal and neonatal effects.

Desflurane, a new volatile anesthetic agent with low blood/gas solubility, has recently been studied in clinical and animal trials but its use in obstetrics has not been adequately evaluated. This prospective study was undertaken to evaluate the maternal and neonatal effects of desflurane in obstetrical patients. Seventy-five healthy parturients undergoing primary or repeat cesarean section were randomly assigned to one of three groups of 25 each, end-tidal 3% desflurane, 6% desflurane or 0.6% enflurane, combined with 50% N2O and O2. All patients had rapid sequence induction of anesthesia with thiopentone sodium followed by succinylcholine for tracheal intubation. After delivery, anesthesia was maintained with reduced concentration of desflurane or enflurane with 67% N2O in O2, supplemented by butorphanol tartrate. Maternal hemodynamic parameters, blood loss and maternal awareness during surgery were monitored. Neonatal outcome was evaluated by Apgar scores, neurological and adaptive capacity scores (NACS), cord blood gas and acid-base status, and time to sustained respiration (TSR). Maternal blood loss did not differ significantly between the three groups and none of the patients developed intraoperative awareness. All three groups responded to psychomotor performance equally fast. Patients in all three groups developed transient hypertension and tachycardia during induction of anesthesia which returned to baseline values in approximately 5 min. Neonatal outcome was equally good in the three groups. More neonates in the 6% desflurane group had TSR > 90 s compared to the 3% desflurane group (P < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Intravenous propofol vs thiamylal-isoflurane for caesarean section, comparative maternal and neonatal effects.

Several studies on propofol (Diprivan) for induction of anaesthesia during caesarean section have demonstrated its safety, however, it safety during maintenance of anaesthesia is not yet fully evaluated. The present study was undertaken to compare the maternal and neonatal effects of propofol or isoflurane in 74 term parturients undergoing primary or repeat caesarean section. Patients were randomly assigned to two groups, propofol group (n = 37) received propofol 1.5-2.5 mg.kg-1 for induction followed by a continuous infusion of propofol of 0.05-0.2 mg.kg-1.min-1. The isoflurane group (n = 37) received thiamylal 3-4mg.kg-1 for induction followed by isoflurane 0.25-0.75% for maintenance. All patients had rapid sequence induction using succinylcholine and endotracheal intubation, 50% N2O and O2 were used in all patients until delivery. After delivery N2O concentration was increased to 67% and intravenous butorphanol (Stadol) was given as needed. Patients in the propofol group had less hypertension after intubation (P < 0.05) and this was also of shorter duration compared to patients in the isoflurane group (5 min vs 10 min respectively). Maternal blood loss as well as intraoperative awareness and recovery time did not differ significantly between the two groups. Neonatal status as ascertained by Apgar scores, cord acid base status and the neurological and adaptive capacity scores (NACS) was equally good in both groups. It is concluded that propofol used for induction and maintenance of anaesthesia is a safe alternative to thiamylal/isoflurane for patients undergoing caesarean section and is associated with less hypertensive response during laryngoscopy and intubation.

Desflurane analgesia for vaginal delivery.

The use of subanaesthetic concentration of inhalational anaesthetic for vaginal delivery offers many advantages to the mother and newborn. Desflurane, with the characteristics of rapid onset and minimal metabolism, may provide better analgesia and safety for labour pain control. Eighty healthy parturients were randomly assigned to receive either desflurane 1.0-4.5% and oxygen (n = 40) or nitrous oxide 30-60% in oxygen (n = 40). Analgesia was assessed using a score from 0 (no relief) to 4+ (excellent analgesia), amnesia for the delivery, blood loss were recorded. Neonates were evaluated by Apgar scores and neurologic and adaptive capacity scores (NACS). Data were analyzed for statistical significance using Student's t-test or Chi-square when appropriate. Analgesia scores were similar for both groups with more amnesia in desflurane group (23% vs 0% P < 0.05). Blood loss did not differ significantly, 364 ml for the desflurane group and 335 ml for the nitrous oxide group. There were no significant differences for neonatal Apgar score at 1 min or at 5 min or the NACS at 2 hr or 24 hr between the two groups. We conclude that desflurane in subanaesthetic doses is safe and effective inhalation agent for normal delivery but might be associated with amnesia.