Epidural pethidine or fentanyl during caesarean section: a double-blind comparison

The onset, quality and duration of analgesia and side-effects of a single bolus dose of either epidural pethidine 50 mg or fentanyl 100 mcg, administered immediately post-delivery, were compared in a randomised, double-blind study of fifty-five women undergoing epidural caesarean section. The onset of effect was more rapid with fentanyl, a significantly larger number of women achieving complete pain relief fifteen minutes post-administration (P less than 0.05). The quality of analgesia was good in both groups and the quality and duration of effective analgesia not significantly different. The incidence and severity of side-effects were low, with no significant difference between groups. One patient in the pethidine group experienced early onset respiratory depression; however, she did not require active treatment. Epidural fentanyl 100 mcg appears to offer a small clinical advantage over pethidine 50 mg for intraoperative use during caesarean section.