This randomized, double-blind, parallel-group, multicenter study evaluated the safety and efficacy of ondansetron (0.1 mg/kg to 4 mg intravenously) compared with placebo in the prevention of postoperative vomiting in 429 ASA status I-III children 1-12 yr old undergoing outpatient surgery under nitrous oxide- and halothane-based general anesthesia. The results show that during both the 2-h and the 24-h evaluation periods after discontinuation of nitrous oxide, a significantly greater percentage of ondansetron-treated patients (2 h 89%, 24 h 68%) compared with placebo-treated patients (2 h 71%, 24 h 40%) experienced complete response (i.e., no emetic episodes, not rescued, and not withdrawn; P < 0.001 at both time points). Ondansetron-treated patients reached criteria for home readiness one-half hour sooner than placebo-treated patients (P < 0.05). The age of the child, use of intraoperative opioids, type of surgery, and requirement to tolerate fluids before discharge may also have affected the incidence of postoperative emesis during the 0- to 24-h observation period. Use of postoperative opioids did not have any effect on complete response rates in this patient population. We conclude that the prophylactic use of ondansetron reduces postoperative emesis in pediatric patients, regardless of the operant influential factors.
IMPLICATIONS: Postoperative nausea and vomiting often occur after surgery and general anesthesia in children and are the major reason for unexpected hospital admission after ambulatory surgery. Our study demonstrates that the prophylactic use of a small dose of ondansetron reduces postoperative vomiting in pediatric patients.
