comparative study of the preemptive dexmedetomidine versus ondansetron effect in post-operative nausea and vomiting after middle ear surgery

Background: nausea and vomiting after operation has high prevalence and cause adverse effect. the aim of this study was to compare the effect of dexmedetomidine with ondansetron in prevention of post-operative nausea and vomiting (ponv) after middle ear surgery under general anesthesia.and saliva gas in traumatic patients under mechanical ventilation.methods: this in this double-blinded clinical trial study, one hundred and sixty-two patients undergoing middle ear surgery under general anesthesia were randomly divided into three groups of 55 each: ondansetron (o), dexmedetomidine (d) and control (c). group o received 0.1 mg/kg of ondansetron, group d received 1 μg/kg/min of dexmedetomidine and group c received 10 cc of normal saline 15 to 20 minutes before surgical incision. after that, the patients were examined in post-anesthesia care unit (pacu) and up to 24 hours after the operation in terms of ponv and other study variables.results: the severity of nausea after operation based on vas (visual analog scale) was significantly different between group o (2.2±0.7) and group d (3.9± 0.7) and group c (5.15±1.3) (p= 0.04). the incidence of vomiting in the first 24h postoperatively was 14.8% in group o, 46.3% in group d and 88.8% in group c (p= 0.003).conclusion: our study showed that ondansetron was better than dexmedetomidine for prevention of ponv after middle ear surgery.