Previous studies have shown that morphine in intravenous PCA provides effective pain control in the postoperative patient, but many patients received morphine have complained side effects. Many studies have suggested that meperidine is less common than morphine in side effects, especially nausea and vomiting. We studied morphine and meperidine in intravenous PCA to compare analgesic effects and side effects in both drugs.

100 ASA class I patients undergoing cesarean section were chosen and randomly divided into two groups. Group I (n=50) received morphine (initial 0.1 mg/kg, maintenance 12.5~62 microgram/kg/hr) and group II (n=50) received meperidine (initial 1 mg/kg, maintenance 0.15~0.75 mg/kg/hr). We compared the analgesia and side effects of group I to those of group II for 2 days. We used Basal-Bolus Infusor R (15 minutes lock-out interval, 0.5 ml/hr, 0.5 ml/one push module, Baxter Healthcare Corporation, USA)) for intravenous PCA.

There were no significant differences in effects of analgesia between both groups. Nausea was more in group I. There were no significant differences in patient's comfort between both groups.

We concluded that meperidine is more useful than morphine in PCA intravenously for post-operative analgesia after cesarean section because there were no significant differences in analgesic effects between both groups but nausea was less in group received meperidine.