Ondansetron Versus Droperidol for Postoperative Nausea and Vomiting

To the Editor: I read with interest the article comparing the efficacy of ondansetron and droperidol, in which the authors concluded that droperidol compared favorably with ondansetron [1]. They used a dose of 4 mg of ondansetron based on previous studies that concluded that ondansetron 4 mg is the optimal dose to prevent postoperative nausea and vomiting (PONV) [2-4]. However, a more recent quantitative review of 53 randomized, placebo-controlled trials showed that there is a dose-response for oral and IV ondansetron [5]. The most efficacious dose of ondansetron IV to prevent PONV was shown to be 8 mg. Thus, 4 mg does not represent the optimal dose of ondansetron for the prevention of PONV. It would be interesting to repeat the study comparing droperidol 1.25 mg with ondansetron 8 mg. Justin Phillips, FRCA Department of Anaesthesia; Frenchay Hospital; Bristol, BS16 1LE UK