EPHEDRINE FOR PREVENTION HYPOTENSION

Background/Aim:. To ameliorate post spinal anesthesia hypotensionin patients undergoing cesarean section. To compare the incidence of maternal hypotension associated withspinal anesthesia for cesarean section when intravenous (IV), intramuscular (IM) or oral prophylactic boluses ofephedrine were used. Design: Prospective randomized double blind study. Setting: Department of anesthesiology,Zainibiae Hospital, Shiraz University, Iran. Period: From: June 2004 to November 2005. Materials and Methods:60 ASA grade I-II pregnant mothers were enrolled. Spinal anesthesia was performed using 60-70 mg of 5% solutionof lidocaine. The patients were divided into three equal groups (n=20). Oral and IM ephedrine (25 mg) wasadministered to the first two groups 30 to 60 minutes before induction of anesthesia (Group A and B, respectively). Inthe last 20 patients, IV Ephedrine (25 mg) was administered immediately after induction of spinal anesthesia (GroupC). Maternal blood pressure and pulse rate was checked every 2 minutes. Hypotension was promptly treated with 10-mg ephedrine boluses. Results: Both IM and IV prophylactic doses of ephedrine significantly decreased the incidenceof hypotension, compared to oral prophylactic dose of ephedrine [4/20 and 0/20 in the IM and IV ephedrine groups,respectively vs. 9/20 in the oral ephedrine group (p < 0.05)]. Conclusion: Oral prophylactic dose of ephedrine is noteffective in preventing hypotension in pregnant women undergoing cesarean section with spinal anesthesia. Therefore,we only recommend a single bolus of IV ephedrine with a dose of 25mg.