ONDANSETRON DECREASES EMESIS AFTER TONSILLECTOMY IN CHILDREN

We performed a double-blind, randomized, placebo-controlled trial to i nvestigate the efficacy and safety of ondansetron in preventing vomiti ng after tonsillectomy with or without adenoidectomy in children. Sixt y children were premedicated with 0.5 mg/kg of oral midazolam and unde rwent inhaled induction and maintenance of anesthesia with halothane a nd nitrous oxide. intravenous morphine 0.075 mg/kg, vecuronium 0.1 mg/ kg, and either ondansetron 0.15 mg/kg (maximum = 8 mg), or saline plac ebo were administered after intravenous catheter placement. All episod es of postoperative vomiting on the day of surgery and the following d ay were recorded. There were no significant differences between the tw o groups with regard to age, weight, sex, time to endotracheal intubat ion, duration of surgery, duration of anesthesia, or number of patient s having adenoidectomy. More patients in the ondansetron group receive d dexamethasone as part of the surgeon's routine protocol (P = 0.03). Twenty-three children (77%) who received ondansetron were emesis-free as opposed to only eight (27%) in the placebo group (P < 0.001). This was especially evident in the number of children who had two or more e pisodes of vomiting; 17 children (57%) who received placebo had two or more episodes of vomiting as opposed to only two children (7%) who re ceived ondansetron. The incidence of emesis on the day after the surge ry did not differ between the two groups. Three children who received ondansetron and one who received placebo complained of abdominal cramp ing on the night of the surgery. There were no other complaints or com plications. Analysis of the 51 children who did not receive dexamethas one revealed similar results. Likewise, there were no significant diff erences between children who received ondansetron plus dexamethasone a nd those who received ondansetron alone. It thus seems that intravenou s ondansetron, 0.15 mg/ kg, when given shortly after induction of anes thesia, safely and effectively decreases the incidence and severity of vomiting in children after tonsillectomy with or without adenoidectom y.