Tropisetron plus dexamethasone is more effective than tropisetron alone for the prevention of postoperative nausea and vomiting in children undergoing tonsillectomy

The 5-HT3 antagonists are effective in reducing postoperative nausea and vo miting (PONV) associated with paediatric tonsillectomy. Although prophylact ic tropisetron can reduce the incidence of PONV by half, the resulting leve l of over 40% is still unacceptably high. The aim of this study was to eval uate the effect of adding dexamethasone to tropisetron. In a blinded study, 59 children (mean age 6.1 years) were administered 0.1 mg.kg(-1) up to 2 m g of tropisetron and 66 children (mean age 5.7 years) received the same dos e of tropisetron plus 0.5 mg.kg(-1) up to 8 mg of dexamethasone. Both drugs were given intravenously during induction of anaesthesia for tonsillectomy . During the inpatient stay of 24 h, the incidence of postoperative vomitin g in the tropisetron alone group was 53% compared with 26% in the combinati on group (P=0.002, chi-squared). A significant reduction in nausea from 53% to 30% was also observed (P=0.02). Parents completed a daily diary for 5 d ays following discharge. Delayed vomiting occurred in 27% and 11% of the tr opisetron and combination therapy groups, respectively (P=0.025) Sixteen pe rcent and 9%, respectively, required medical attention (P=0.27). Tropisetro n plus dexamethasone is more effective than tropisetron alone in reducing t he incidence of PONV following paediatric tonsillectomy.