5-HT3 receptor antagonists vs traditional agents for the prophylaxis of postoperative nausea and vomiting

Numerous antiemetics have been studied for the prevention of postoperative nausea and vomiting (PONV) including traditional agents (metoclopramide, perphenazine, prochlorperazine, cyclizine and droperidol) and the 5-HT3 receptor antagonists (ondansetron, dolasetron, granisetron and tropisetron). The results have been divergent and inconsistent. The purpose of this quantitative systematic review was to evaluate the effectiveness of 5HT3 receptor antagonists compared to traditional antiemetics for the prevention of PONV METHODS: A systematic search of the English language literature using computerized MEDLINE, EMBASE, and Pre-MEDLINE databases from 1966 to October 1999 and a manual search of references from retrieved articles were performed. Individual efficacy and adverse effect data was extracted from each of the studies according to a predefined protocol. The summary odds ratios were calculated using the Dersimonian and Laird method under a random effects model.

A total of 41 trials met our pre-defined inclusion criteria and were included in our analysis. Results in the 32 studies examining PONV indicated a 46% reduction in the odds of PONV in the 5-HT3-treated group (0.54 [95% CI 0.42-0.71], P < 0.001). Evaluation of PONV by traditional antiemetic agent demonstrated a 39% reduction compared with droperidol (0.61 [95% CI 0.42-0.89], P < 0.001) and a 56% reduction compared with metoclopramide (0.44 [95% CI 0.31-0.62], P < 0.001). Results in the 34 studies examining vomiting indicated a 38% reduction in the odds of vomiting in the 5-HT3-treated group (0.62 [95% CI 0.48-0.81], P < 0.001).

The 5-HT3 receptor antagonists are superior to traditional antiemetic agents for the prevention of PONV and vomiting. The reduction in the odds of PONV and vomiting is significant in the overall analysis and the subgroup analyses comparing 5-HT3 receptor antagonists with droperidol and metoclopramide.