Objective: The aim of the present study was to test the efficacy of epidural nalbuphine 5 mg for prevention of morphine-induced pruritus.
Material and method: Parturients, ASA I-II scheduled for elective cesarean section under epidural anesthesia were randomized into 3 groups: the placebo group, N-5 group, and N-10 group received 4 ml epidural solution containing morphine 4 mg plus either saline, nalbuphine 5 mg, and nalbuphine 10 mg respectively. Pain score at rest and on movement, incidence and severity of pruritus, sedation score, and pethidine consumption were recorded for 24 hours.
Results: The 182 parturients were randomized into 60 in the placebo group, 61 in the N-5 group, and 61 in the N-10 group. The severity of pruritus was significantly lower at 3, 6, 9 and 12 h postpartum in the N-5 group and the N-10 group had a lower degree of pruritus at 3 and 6 h postpartum compared to placebo. The VAS pain scores at rest and on movement were significantly higher in the N-10 group at 3, 6, 9, 12 and 18 h postpartum compared to the placebo and significantly higher at 3 h, 6 h postpartum compared to the N-5 group (p < 0.05). Patient's satisfactions were high in all groups without any significant difference between groups.
Conclusion: Epidural nalbuphine 5 mg reduced severity of morphine induced pruritus for 12 h with statistically significant different advantages over epidural nalbuphine 10 mg without anti-analgesic effect. However the difference is too small to convey into clinical significant advantage.