Epidural nalbuphine for post cesarean epidural morphine induced pruritus

The aim of the present study was to test the efficacy of epidural nalbuphine 5 mg for prevention of morphine-induced pruritus.

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.

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.

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.