Prophylactic intravenous ondansteron and nalbuphine for reduction of subarachnoid fentanyl-induced pruritus in patients undergoing elective cesarean delivery

ABSTRACT

Addition of fentanyl to spinal anaesthesia with bupivacaine improves the quality and success of anaesthesia. However, it has a frequent incidence of pruritus and a substantial incidence of nausea and vomiting. tn this placebo controlled study, we compared the prophylactic efficacy of ondansetron and nalbuphine for the prevention of intrathecal fentanyl-induced pruri tus after cesarean delivery. Ninety elective parturients were assigned to one of the groups Group 0 [Ondansetron 8mg IV n=30], Group N [Nalbuphine 4mg IV n=30] and Group S [Saline 0.9% IV n=30] as placebo. The study drugs were administered immediately after the umbilical cord was clamped. The occurrence of pruritus, nausea, pain and adverse reactions from ondansetron and nalbuphine was evaluated by pruritus score, 4-point rating score and visual analog scale respectively, at 15 minutes in the first hour after the injection of the study drugs. Afterward, evaluations were performed at 1, 2, 3 and 4 hours after the administration of study drugs. The overall incidence of pruritus, it was significantly more frequent in Group S [62%] compared with both Group 0 [43%] and Group N [42.5%]. The incidence of pruritus during the different study intervals showed significant increase in Group S compared with the other groups mainly at 45mm and 1 hour. The pruritus score was significantly different between Group 0 and Group S and between Group N and Group S [p<0.0S] respectively, it was mostly mild in Group 0 and Group N and mostly moderate in Group S. Treatment for pruritus was requested by patients in, 10%, 11% and 29% of patients in the Group 0, Group N and Group 5, respectively. There was no significant difference in the overall incidence and the severity of nausea andlor vomiting at different time study intervals for all groups. However, the number of patients requesting treatment for nausea and/or vomiting was significantly less in Group 0 and Group N when compared with Group S. No significant adverse reactions related to the study drugs reported during the different study intervals. Although IV ondansetron and nalbuphine significantly decreased the incidence of of fentanyl-induced pruritus more than placebo after cesarean delivery, further studies are recommended to show the other possible mecha nisms might be involved in the pathogenesis of fentanylinduced pruritus