A randomised, double-blind study was conducted on 90 ASA I & II patients undergoing middle ear surgery to compare the efficacy of ondansetron, dexamethasone and a combination of Ondansett on+dexamethasone for the prevention of postoperative nausea and vomiting. Group I patients received ondansetron (0. 1 mg/kg), group IIpatients received dexamethasone(0.1z mg./Kg) while group III received ondansetron (0.1 mg./kg) + dexamethasone (0.15 mg/kg), 10 minute before induction of general anaesthesia. A standardised general anaesthetic technique was employed through out. A complete response, defined as no postoperative nausea and vomiting and no need for another rescue antiemetic during the first 4 hours after anaesthesia was achieved in 58%, 55% and 83% of patients who had received ondansetron, dexamethasone and ondansetron + dexamethasone respectively. The corresponding incidence during the next 20 hours after anaesthesia was 54%, 47% and 85%. No clinically important adverse effects were observed in any of the groups. We conclude that prophylactic therapy with ondansetron +dexamethasone,one is superior in the prevention of postoperative nausea and vomiting after middle ear surgery.
Keywords: Antiemetics; Dexamethasone; Nausea; Ondansetron; Surgery; Vomiting; middle ear.