Ondansetron Alone Versus in Combination with Olanzapine for Prevention of Postoperative Nausea and Vomiting in Patients Undergoing Elective Middle Ear Surgeries: A Randomized Controlled Trial

Abstract

Introduction: POSTOPERATIVE nausea and vomiting (PONV) is a common and distressing complication following anaesthesia and surgery. Olanzapine, an atypical antipsychotic with broad antiemetic properties, has emerged as a promising agent for PONV prophylaxis. The present study compared the efficacy of ondansetron alone with that of ondansetron combined with olanzapine in preventing PONV.

Methods: A prospective, double-blind, clinical study was conducted among female patients of 18 - 60 years of age after obtaining informed, written consent. A total of 60 patients undergoing middle ear surgeries under general anaesthesia were divided into two groups. Group A, received Tab. Olanzapine 2.5mg preoperatively along with Inj. Ondansetron 4mg IV intraoperatively 30 minutes before extubation, and Group B received a placebo tablet 1 hour preoperatively and Inj. Ondansetron 4mg IV alone. Occurrence of nausea of PONV was noted from 0 to 24 hours postoperatively. Post-operative incidence of sedation was also noted using Ramsay agitation-sedation scale. Any adverse reactions and need for rescue antiemetics was noted.

Results: The demographic and intraoperative characteristics were comparable between the two groups without any statistically significant differences. Group A demonstrated slightly lower PONV rates as compared to Group B with p value 0.43. Postoperative sedation was assessed using Ramsay Sedation Scale and no sedation was noted in either study groups. Fewer patients in Group A required rescue antiemetics compared to patients in Group B. None of the adverse effects noted were significantly different between the groups.

Conclusion: It was concluded from the study that the use of Olanzapine did not show a significant advantage in preventing PONV as inferred from the comparable incidences between the two groups.