Efficacy of ondansetron in prophylaxis of postoperative nausea and vomiting in patients following infratentorial surgery: a placebo-controlled prospective double-blind study

Abstract

In a prospective double blind placebo-controlled study, 45 patients scheduled for infratentorial surgery were randomly allocated into two groups. Five patients were later excluded from the study because of various reasons. Out of 40 analyzable patients, 20 received IV Ondansetron (4 mg), whereas the other 20 received the matching placebo approximately 1 hour before the skin closure. After conclusion of surgery and tracheal extubation, all patients were monitored in the recovery room for post operative nausea and vomiting (PONV) for 48 hours. The incidence of PONV within the first 24 hours was found to be 50% and 10% in the placebo and ondansetron groups, respectively (p<0.05). After 24 hours, however, both groups were comparable in relation to the incidence of emesis. Rescue antiemetic (RAE) was required in nine (45%) patients in the placebo group and in two (10%) patients in the Ondansetron group (p<0.05). A significantly higher number of patients remained sedated postoperatively in the Ondansetron group than in the placebo group (p<0.05). One patient in the Ondansetron group had protracted diarrhea for 48 hours postoperatively. These results indicate that administration of IV Ondansetron (4 mg) 1 hour before skin closure effectively reduces PONV after infratentorial surgery, and does not have significant adverse effects.