Tropisetron for prevention of nausea and vomiting in children undergoing tonsillectomy and/or adenoidectomy

Background: Postoperative nausea and vomiting (PONV) after tonsillectomy is a common problem in children. Tropisetron is a new 5HT(3) receptor antagon ist and is successfully used in paediatric patients receiving cancer therap y. The aim of the study was to assess efficacy and safety of a single intra venous dose of tropisetron for prevention of PONV in paediatric patients at risk for postoperative vomiting. Methods: In a randomised double-blind, placebo-controlled trial, we studied 98 children aged 2-12 years undergoing tonsillectomy or adenotonsillectomy . Patients received placebo or tropisetron 0.1 mg (=0.1 ml)/kg body weight immediately after induction of anesthesia. A standard general anesthetic te chnique (Sevoflurane/N2O/O-2 without neuromuscular blockers or opioids) was used. Perioperative vital signs,grade of sedation and episodes of postoper ative nausea and vomiting were recorded. Results: No vomiting episodes occurred in 65.3% of the tropisetron treated patients compared to 34.7% of the placebo group (p=0.0024). Only 10.2% of t he tropisetron treated patients vomited more than 3 times compared to 22.4% of the control patients (p=0.0004). The need for antiemetic rescue medicat ion was significantly lower in the study group (10.4%) compared to 28.6% (p =0.025). No significant adverse effects of the study medication were shown. Conclusion: A single intravenous prophylactic dose of tropisetron effective ly reduces the incidence of PONV during the first 24 postoperative hours af ter tonsillectomy and/or adenoidectomy. Because of the low incidence of adv erse effects,the prophylactic use of tropisetron seems to be safe and justi fied in paediatric surgical patients at high risk for postoperative vomitin g.