Oral ondansetron decreases vomiting after tonsillectomy in children

Abstract

Vomiting is a common, unpleasant aftermath of tonsillectomy in children. Intraoperative intravenous ondansetron (OND) reduces vomiting after this operation. Our doubleblind, placebocontrolled, randomized investigation studied the effect of the oral form of OND on vomiting after outpatient tonsillectomy in children. We studied 233 healthy children age 2-14 yr undergoing elective tonsillectomy. Subjects were given placebo (PLAC) or OND 0.1 mg · kg-1 rounded off to the nearest 2 mg one hr before surgery. Anaesthesia was induced with either propofol or halothane/N2O. Vecuronium 0.1 mg · kg-1 was administered at the discretion of the anaesthetist. Anaesthesia was maintained with halothane/N2O, 50 μg · kg-1 midazolam iv and 1-1.5 mg · kg-1 codeine im. At the end of surgery, residual neuromuscular blockade was reversed with neostigmine and atropine. All episodes of inhospital emesis were recorded by nursing staff. Rescue antiemetics in the hospital were 1 mg · kg-1 dimenhydrinate ivfor vomiting × 2 and 50 μg · kg-1 droperidol iv for vomiting × 4. Parents kept a diary of emesis after discharge. Postoperative pain was treated with morphine, codeine and/or acetaminophen. The two groups were similar with respect to demographic data, induction technique and anaesthesia time. Oral OND (n = 109) reduced postoperative emesis from 54% to 39%, P < 0.05. This effect was most dramatic inhospital, where 10% of the OND-patients and 30% of the PLAC-group vomited, P < 0.05. The OND-subjects required fewer rescue antiemetics, 7% vs 17%, P < 0.05. In conclusion, oral ondansetron decreased the incidence of vomiting after outpatient tonsillectomy in children. © 1995 Canadian Anesthesiologists.