Sub-hypnotic dose of propofol as antiemetic prophylaxis attenuates intrathecal morphine-induced postoperative nausea and vomiting, and pruritus in parturient undergoing cesarean section — a randomized control trial

BACKGROUND: Postoperative Nausea and Vomiting (PONV) is a dreadful and uncomfortable experience that significantly detracts patients’ quality of life after surgery. This study aimed to examine the antiemetic effect of a single sub-hypnotic dose of propofol as prophylaxis for PONV. METHOD: In this prospective, double-blind, randomized control trial, 345 parturients presented for elective cesarean section at the Obstetric unit of Tamale Teaching Hospital were recruited. Each recruited parturient was randomly assigned to one of three groups; Propofol group (n = 115) represented those who received propofol 0.5 mg/kg, Metoclopramide group (n = 115) represented those who received metoclopramide 10 mg and, Control group (n = 115) represented those who received 0.9% saline. Spinal anesthesia with 0.5% hyperbaric bupivacaine 7.5–10 mg, and intrathecal morphine 0.2 mg was employed for the anesthesia. RESULTS: The data indicate that 108 (93.9%) parturients from the control group, 10 (8.7%) from the propofol group and 8 (7.0%) from the metoclopramide group experienced some incidence of PONV. There was no significant difference in the incidence of PONV (nausea, vomiting, and none) between the propofol and the metoclopramide groups (P = 0.99; 0.31; and 0.35 respectively). Parturients who received antiemetic agents were 105 (97.2%), 1 (10.0%) and 3 (37.5%) from the control, propofol and metoclopramide groups respectively. The data indicated that 98 (85.2%) parturients from the control, 3 (2.6%) from propofol group, and 100 (87.0%) from the metoclopramide group experienced some levels of pruritus. There was a significant difference in the incidence of pruritus (mild, moderate, and no pruritus) between the metoclopramide and propofol groups (P < 0.01; P < 0.01; and P < 0.01 respectively). CONCLUSION: A sub-hypnotic dose of propofol is effective as metoclopramide in the prevention of PONV in parturient undergoing cesarean section under spinal anesthesia with intrathecal morphine. Sub-hypnotic dose of propofol significantly reduces the incidence of postoperative pruritus following intrathecal morphine use. TRIAL REGISTRATION: Current control trial, registered at ISRCTN trial registry: ISRCTN15475205. Date registered: 03/04/2019. Retrospectively registered.