Ondansetron and dolasetron provide equivalent postoperative vomiting control after ambulatory tonsillectomy in dexamethasone-pretreated children.

Unlabelled: In this prospective, randomized, double-blinded, placebo-controlled study, we compared the incidence of emesis and 48-h recovery profiles after a single dose of preoperative ondansetron versus dolasetron in dexamethasone-pretreated children undergoing ambulatory tonsillectomy. One-hundred-forty-nine children, 2-12 yr old, ASA physical status I and II, completed the study. All children received standardized perioperative care, including premedication, surgical and anesthetic techniques, IV fluids, analgesics, and rescue antiemetic medications. Patients were randomized to receive ondansetron 0.15 mg/kg, maximum 4 mg (Group 1); dolasetron 0.5 mg/kg, maximum 25 mg (Group 2); or saline placebo (Group 3) IV before the initiation of surgery. In addition, all patients received dexamethasone 1 mg/kg (maximum 25 mg). Rescue antiemetics were administered for two or more episodes of retching/vomiting. The incidence of retching/vomiting before home discharge did not differ between the ondansetron and dolasetron groups and was significantly less frequent compared with the placebo group (10%, Group 1; 8%, Group 2; 30%, Group 3). Similar results were obtained at 24-48 h after discharge (6%, Groups 1 and 2; 18%, Group 3). The need for rescue antiemetics administered after the second retching/vomiting episode was significantly less in Groups 1 (4%) and 2 (6%) compared with Group 3 (22%) before home discharge. The complete response rate, defined as no retching/vomiting and no antiemetic for 48 h, was significantly increased in Groups 1 (76%) and 2 (74%) compared with Group 3 (44%). The antiemetic efficacy of prophylactic ondansetron and dolasetron was comparable in dexamethasone-pretreated children undergoing ambulatory tonsillectomy.

Implications: The efficacy of a single dose of prophylactic ondansetron versus dolasetron in conjunction with dexamethasone was studied on posttonsillectomy retching/vomiting and 48-h recovery in children 2-12 yr old. Compared with placebo, ondansetron and dolasetron produced comparable reductions in the incidence of retching/vomiting and the need for rescue antiemetics.