Comparison of ondansetron, dimenhydrinate versus placebo as PONV prophylaxis for outpatient gynecological laparoscopy

This is a study comparing ondansetron, dimenhydrinate versus placebo as PONV prophylaxis for outpatient gynecologic laparascopy. Postoperative nausea and vomiting (PONV) is very common following ambulatory gynecological laparoscopy. Prophylactic antiemetic therapy if safe, effective and affordable may reduce the incidence of PONV, expedite hospital discharge and improve patient satisfaction. After institutional review board approval, informed written consent was obtained form 87 ASA I–II women undergoing ambulatory gynecological laparoscopy. In a random and double blind fashion the women were divided into three groups receiving either ondansetron 8 mg, dimenhydrinate 50 mg or placebo. A standard anesthetic technique with propofol, fentanyl, mivacurium, nitrous oxide and isoflurane was used. Measurements of nausea, emesis, pain, drowsiness, and satisfaction and recovery milestones were recorded. Psychomotor recovery was evaluated using p deletion and digit symbol substitution (DSS) test. There was no difference in the groups with respect to demographic data. Dimenhydrinate prolonged immediate recovery and impaired psychomotor recovery, but there was no difference in postanesthesia care unit (PACU) or hospital discharge. The incidence of PONV was minimal. The visual analogue score (VAS) for nausea was only 1 on a scale from 0–10 cm in all groups. Only one patient in the placebo group experienced PACU emesis. The incidence and severity of PONV was so low, even in the placebo group that the use of prophylactic antiemetic therapy cannot be justified.