Background and aims: The present study evaluated the effects of two 5-HT3 serotonin receptor antagonists; granisetron and palonosetron on hemodynamics, sensory, and motor blockade induced by intrathecal bupivacaine in patients undergoing abdominal hysterectomy.
Material and methods: In total, 126 female patients (ASA I and II physical status) undergoing abdominal hysterectomy under spinal anesthesia with intrathecal bupivacaine were randomly divided into three groups out of which 40 patients in each group were evaluated for final outcome. Group G received intravenous 1 mg granisetron, group P received intravenous palonosetron 0.075 mg, and group C received intravenous normal saline. Study drug was given 5 min before the spinal anesthesia. Systolic, diastolic and mean arterial blood pressure, heart rate, sensory and motor blockade were assessed.
Results: The systolic blood pressure, diastolic blood pressure, mean arterial pressure, and heart rate showed no significant differences among the three groups. Time to reach peak sensory block and modified Bromage 3 motor block, time to two segmental regression of sensory block, and motor regression to modified Bromage score of 0 were not statistically different among the three groups. Although statistically significant early regression of sensory block to segment S1 was seen in group G as compared to group P and group C, it was of no clinical significance. The incidence of nausea and vomiting was significantly lower in group G and P.
Conclusion: Intravenous administration of granisetron and palonosetron before intrathecal bupivacaine does not attenuate the hemodynamic changes in patients undergoing abdominal hysterectomy. Further, both 5-HT3 receptors antagonists do not have clinically significant effects on the spinal blockade produced by hyperbaric bupivacaine.
Keywords: Bupivacaine; granisetron; palonosetron; spinal anesthesia.