Comparison of Ondansetron and Ondansetron with Propofol to Prevent Intrathecal Morphine-induced Pruritus in Patients Undergoing Cesarean Section

Abstract

Background: Intrathecal morphine is the frequently used technique for cesarean section because of the safety and postoperative analgesia efficacy. However, pruritus is the most common side effect associated with spinal opioid administration. It is often difficult to treat and may be unpleasant for patient leading to patient dissatisfaction. Objective: This randomized controlled trial aimed to compare the effect of ondansetron and ondansetron with propofol to prevent intrathecal morphine-induced pruritus in patients undergoing cesarean section. Methods: 90 patients scheduled for cesarean section under spinal anesthesia with intrathecal morphine 0.2 mg added to 10 -12 mg bupivacaine were randomly allocated into two groups. After child birth, group 1(n=45) received intravenous 8 mg ondansetron. Group 2 (n=45) received intravenous 8 mg ondansetron and propofol 0.5 mg/kg. The incidence and severity of pruritus, postoperative nausea and vomiting and other complication were assessed during recovery and at 4, 8, 24 hours following intrathecal morphine. Results: The incidence of pruritus was significantly less frequent in patients who received ondansetron with propofol compare with those who received ondansetron alone (31.1% vs. 55.5%, p=0.029 at 4 hours and 57.7% vs. 75.6%, p=0.037 at 8 hours). The number of patients requesting treatment for moderate to severe pruritus was significantly lower in the ondansetron with propofol group than the ondansetron group (6.7% vs 24.4%, p=0.02). There was no significant difference between two groups in PONV. Conclusion: Ondansetron with propofol prophylaxis significantly reduced incidence and severity of intrathecal morphine induced pruritus compared with ondansetron alone in patient undergoing cesarean section.