Failure of prevention against postoperative vomiting by ondansetron or prochlorperazine in patients undergoing gynecological laparoscopy.

Background : Ondansetron has been approve d for the treatment and prevention of postoperative emesis. Since it is presumably considered to possess potent antiemetic effect with fewer side effects, the administration of ondansetron to inhibit emesis in patients following gynecological laparoscopic surgery might be recommendable. Hence, we examined the effects of intravenous ondansetron at dosage of 4 and 8 mg in comparison with intravenous prochlorperazine at 5 mg and placebo. Methods: A total of 120 patients were allocated randomly into 3 groups. Group 1patients whose rvedas control were given NaCl 0.9% 4 mL (placebo) intravenously (i.v.); patients in group 2 and group 3 we re given ondansetron 4 mg ondansetron 8 mg i.v. respectively; patients in group 4 were given prochlor perazine 5 mg i.v. Premedication was omitted. Results: Logistic regression analysis adjusted for prognostic factors revealed no significant difference between 5 mg prochlorperazine group and 4 mg or 8 m g ondansetron group as compared over the 24 h study period. Conclusions : The results of this study suggest that i.v. 4 or 8 mg ondansetron and 5 mg prochlorperazine were not effective in prevention of postoperative emesis in patients under going gynecological laparoscopy. Since the cost of ondansetron is high, its routine use for prevention against postoperative nausea and vomiting is not bere commended clinically because of its uncertain benefit.