PROPHYLACTIC EPHEDRINE AND HYPOTENSION ASSOCIATED WITH SPINAL-ANESTHESIA FOR CESAREAN DELIVERY

Hypotension commonly accompanies induction of spinal anesthesia for ce sarean section. To determine whether intravenous ephedrine prophylaxis would benefit prehydrated obstetrical patients presenting for electiv e cesarean section? we studied 30 patients randomly assigned to one of three experimental groups. All patients were preloaded with crystallo id (15 ml/kg), given spinal anesthesia and positioned with left uterin e displacement (LUD). During induction, all patients received a 2 mi i ntravenous bolus and intravenous infusion of the study drug or placebo . The control group (n=10) received a saline bolus and saline infusion , the bolus group (n=10) received an ephedrine bolus (10 mg) and a sal ine infusion and the infusion group (n=10) received a saline bolus and a two-stage ephedrine infusion (20 mg over 12 min). After induction o f anesthesia, systolic blood pressure decreased in the first 5 min in all groups. Hypotension occurred in 6/10 control patients, 5/10 bolus patients and 5/10 infusion patients. The amount of supplemental ephedr ine required to treat hypotension did not differ among groups. Althoug h the efficacy of ephedrine prophylaxis for hypotension associated wit h spinal anesthesia for elective cesarean section cannot be establishe d by the small number of patients studied, this practice does not appe ar to be clinically relevant at the doses studied.