Comparison of tropisetron, droperidol, and saline in the prevention of postoperative nausea and vomiting after gynecologic surgery.

Abstract

This study was performed to compare the efficacy of tropisetron, droperidol, and saline in the prevention of postoperative nausea and vomiting (PONV) and to compare the possible adverse effects of these drugs in gynecologic incontinence surgery. Using a randomized, double-blind study design, we studied 150 women undergoing gynecologic incontinence surgery with standardized general anesthesia. At the end of surgery, the patients received either tropisetron 5 mg, droperidol 1.25 mg, or 0.9% saline intravenously (i.v.). As a rescue antiemetic, the patients received metoclopramide 10 mg i.v.. The episodes of nausea, retching, and vomiting; the need for rescue treatment; and the type and severity of adverse events were recorded at four occasions during the 48-h observation period. Pain, anxiety, drowsiness, and general satisfaction were also evaluated on a linear numerical scale of 0-10. Complete response (no PONV within the 48-h observation period) occurred similarly in the study groups (tropisetron 25%, droperidol 22%, and placebo 18%). Tropisetron and droperidol had no effect on the incidence of nausea and retching. However, the incidence of vomiting was significantly less in the tropisetron group than in the placebo group (tropisetron 19%, droperidol 45%, and placebo 57%). The number of emetic episodes (retching and/or vomiting) per patient within 48 h was significantly decreased under tropisetron when compared with placebo (tropisetron 2.5 +/- 3.4, droperidol 4.2 +/- 6.1, placebo 5.9 +/- 7.1). With regard to adverse events, the patients in the droperidol group had significantly more anxiety than the placebo group (2-6 h postoperatively), more drowsiness than the tropisetron and placebo groups (0-2 h postoperatively), and more dissatisfaction than the tropisetron (0-6 h postoperatively) and placebo groups (2-6 h postoperatively). We conclude that tropisetron given 5 mg i.v. during anesthesia in gynecologic incontinence surgery effectively prevents vomiting but not nausea and retching, while 1.25 mg i.v. droperidol fails to prevent any of these emetic symptoms and results in adverse events.