Comparison of the antiemetic effects of ondansetron and dexamethasone on middle ear surgery.

Objective: To compare the antiemetic efficacy of ondansetron and dexamethasone in adults undergoing middle ear surgery.

Methods: This clinical research took place in the Faculty of Medicine, Gazi University, Turkey between January to December 2004. The study included 60 cases, classified by the American Society of Anesthesiology physical status group I-II, who underwent middle ear surgery. We carried out anesthesia induction with 5 mg x kg(-1) sodium thiopental and performed muscle relaxation with 0.5 mg x kg(-1) atracurium to be followed by orotracheal intubation. Anesthesia was maintained at 5 L x min(-1) gas flows with 2-3% sevoflurane inhalation in 70/30% O(2)/N(2)O. We randomly distributed the cases into 2 groups, and the first group (Group O) was administered with 4 mg ondansetron intravenously (IV) at the stage of surgical skin closure and the second group (Group D) with 5 mg dexamethasone IV immediately after anesthesia induction. In the first 24 hours postoperatively, nausea vomiting score (NVS) and nausea, vomiting frequency, Metamizole-Na and non-steroidal anti-inflammatory drug use, the need for additional antiemetics and cost as well as the number of cases with nausea, vomiting and the need for extra antiemetics during 0-4, 4-12 and 12-24 hours were recorded, and their distribution to groups was evaluated.

Results: The NVS was 0 (0-0) in group O compared with 1 (0-3) in group D (p=0.003). The use of additional antiemetics was found to be significantly lower in group O (1 +/- 0.6) compared with group D (3.70 +/- 1.02) (p=0.028). In comparing the cost, group O (9.8 dollars) was found to have a significantly higher cost compared with group D (1.1 dollars) (p<0.0001).

Conclusion: Ondansetron had a more significant effect on nausea and vomiting in the early period, however, no difference was found after 4 hours of administration. Furthermore, dexamethasone was found to cost less compared with ondansetron.