A systematic review of the antiemetic efficacy of prophylactic ondansetron compared with droperidol and with metoclopramide in children

Objective: To determine the pooled relative risk (RR) of prophylactic ondansetron relative to droperidol and relative to metoclopramide for prevention of post-operative (p.o.) vomiting in children. Design: Meta- analysis of published randomized trials of p.o. emesis. Study Selection: Of 22 articles reviewed in detail by the three authors, 19 met the eligibility criteria. The meta-analysis of ondansetron versus droperidol included 13 studies. The metoclopramide meta-analysis included 8 studies. Main Outcome: P.o. vomiting over a 24-hour period. Results: There were consistent statistically significant benefits of ondansetron compared with droperidol (pooled RR 0.67, 95% confidence interval 0.49-0.90, p=0.0092) and with metoclopramide (0.56, 0.44-0.71, p<0.001). There was no evidence of heterogeneity among either the droperidol studies (p for homogeneity=0.17) or the metoclopramide studies (p=0.25). There was no apparent effect of drug dose, study quality or type of outcome (vomiting or nausea) nor were the significant results likely to be due to publication bias. Conclusions: Prophylactic ondansetron prevented p.o. emesis compared with both droperidol and metoclopramide (numbers needed to treat being 11 and 8 respectively) in children. The relative cost-effectiveness of the drugs in routine clinical practice remain to be evaluated. Summary statement: Prophylactic ondansetron is effective and superior to droperidol and metoclopramide in the prevention of emesis in children. Relative cost-effectiveness of the drugs in routine clinical practice needs to be explored.