ABSTRACT
Background: Dexamethasone is useful as prophylaxis for postoperative nausea and vomiting (PONV). Aim: To study the short term efficacy of dexamethasone to treat PONV in adults without prophylaxis, and compare its efficacy with that of droperidol and ondansetron. Material and methods: A prospective study was performed with 120 consecutive adult patients presenting PONV in the postanesthesia care unit (PACU) at a University teaching hospital. During the occurrence of PONV, patients were randomized to receive in a double blind manner dexamethasone 8 mg IV (Group 1, n=40), droperidol 1.25 mg IV (Group 2, n=40), or ondansetron 2 mg IV (Group 3, n=40). Risk factors for PONV were recorded. Evaluations were made until discharge from the PACU and included presence of PONV, degree of sedation, and other potential adverse effects of the study drugs. Short term efficacy was defined as the percentage of patients free of PONV during all the stay in PACU after treatment. Results: General data was similar for the 3 groups. Mean ± SD stay in PACU after treatment was 101±34 minutes in Group 1, 93±33 minutes in Group 2, and 99±32 minutes in Group 3 (NS). Short term efficacy (CI 95%) was 55% (40-70%) in Group 1, 90% (81-99%) in Group 2, and 63% (48-78%) in Group 3 (p <0.05 for group 2 vs 1 and 3). There were no adverse effects attributable to the study drugs. Conclusions: Short term efficacy of dexamethasone to treat PONV was similar to ondansetron, but inferior to droperidol. Further studies are needed to define the duration of this effect of dexamethasone.