A Comparison of Commonly Used Anti-Emetics for the Prevention of Emetic Sequelae after a Major Gynaecological Surgery

S Sharma, N Abdullah
Correspondence: Dr S Sharma, ssharma@pc.jaring.my

ABSTRACT
Study Design Prospective, randomized, double-blind, placebo-controlled study involving one hundred ASA I-II patients undergoing major gynaecological surgery.
Objective To study anti-emetic efficacy of intravenous (IV) ondansetron (4 mg), droperidol (2.5 mg), metoclopramide (10 mg), and placebo.
Patients and Methods 100ASA physical status I-II undergoing major gynaecological surgery were randomized to receive intravenously (IV), one of the four test drugs 10 minutes before the end of anaesthesia. The incidence of postoperative nausea and vomiting following a standard anaesthetic technique was assessed.
Results A significantly large number of patients who received ondansetron (88%) and droperidol (72%) were free of emetic sequelae when compared to placebo (41%); p < 0.05 (power of this observation is approximately 80% at the given significance level). Metoclopramide was ineffective. Patients given droperidol were significantly more sedated than those receiving ondansetron; p < 0.05. This is not surprising, as the dose of droperidol used in this study was higher than that currently recommended because we found lower doses to be ineffective in controlling nausea and vomiting in this group of patients.
Conclusion It was concluded that, of the drugs studied ondansetron is the best choice for anti-emetic prophylaxis after major gynaecological surgery.

Keywords: pharmacology, ondansetron, droperidol, complications, nausea and vomiting
Singapore Med J 2000; 41(4): 147-150