Comparison of different doses of epidural morphine for pain relief following cesarean section

Although epidural opioid analgesia after cesarean section can provide excellent postoperative pain relief, serious complications may occur after epidural morphine. Therefore, we performed this study to compare the efficacy and side effects of three different doses of epidural morphine for analgesia following cesarean section. Ninety healthy pregnant women who underwent cesarean delivery were randomly assigned to receive either 2.5, 3 or 4 mg of epidural morphine for postoperative analgesia. Pain intensity at rest and on movement using a visual analogue scale (0-10) was regularly assessed for 48 hours, the time to first analgesic requirement, the total analgesic dose, patient satisfaction and side effects were recorded. Chi square and ANOVA tests were used for statistical analyses. We were unable to demonstrate any difference in pain relief, patient satisfaction, and side effects among the three groups. Epidural morphine provided sufficient pain relief for approximately 24 hours. About 27 per cent of the patients from each group were pain-free for up to 48 hours without further analgesics. Mild pruritus and nausea occurred in all three groups and there was no significant difference between them. No serious complications were observed. In conclusion low dose epidural morphine is effective in providing adequate analgesia following cesarean delivery.