Efficacy of ondansetron for prevention of postoperative-nausea and vomiting after outpatient ear surgery under local anesthesia

Objective: To assess the efficacy and safety of intravenous ondansetron (4 mg) for the prevention of nausea and vomiting after middle ear surgery unde r local anesthesia. Setting: The study was conducted by Division of Otorhinolaryngology in Prin ce of Wales Hospital, which is a tertiary referral center and teaching hosp ital for The Chinese University of Hong Kong. Study Design: A double-blind randomized controlled trial. Patients: Fifty-e ight Chinese patients undergoing tympanoplasty under local anesthesia from July 1995 to June 1997 were recruited. The mean age of patients was 42.8 ye ars (range 18-71 years). Intervention: Patients were randomly allocated to receive a single dose of intravenous ondansetron (4 mg) (n = 29) or placebo (n = 29) immediately bef ore surgery. Main Outcome Measures: Patients were assessed far severity and frequency of postoperative nausea and vomiting at the Ist, 2nd, 4th, 8th, and 24th hour s after:middle ear surgery. Results: Female patients showed a higher prevalence of postoperative nausea and vomiting. Twenty-eight percent of the patients experienced postoperati ve nausea, of whom 14% also experienced vomiting. Although the ondansetron group demonstrated a lower prevalence of postoperative nausea and vomiting (PONV) (24% nausea and 10% vomiting) than the placebo group (31% nausea and 17% vomiting), significant reduction in postoperative vomiting only occurr ed in the first postoperative hour (p = 0.038). No complications or adverse side effects were found to be associated with the use of ondansetron. Conclusions: Single-dose ondansetron (4 mg) given intravenously preoperativ ely significantly reduces postoperative vomiting in patients after tympanop lasty under local anesthesia and causes no adverse effects.