Double-blind comparison of ondansetron, droperidol and saline in the prevention of postoperative nausea and vomiting

Abstract

We have compared the efficacy of ondansetron with droperidol and saline in the prevention of postoperative nausea and vomiting (PONV) in 120 ASA I and II patients undergoing hip and knee replacements and femoral resections. They received a standardized combined extradural and general anaesthetic and at the end of surgery were allocated randomly to receive droperidol 1.25 mg, ondansetron 4 mg or 0.9% saline in a 25-ml bag. An extradural mixture containing 0.5% plain bupivacaine 10 ml, fentanyl 500 micrograms and saline 30 ml was infused and PONV assessed for 24 h. Both ondansetron and droperidol were superior to saline in preventing vomiting (P < 0.01) although there was no significant difference between them. The incidence of vomiting was 17% for ondansetron, 18% for droperidol and 45% for saline. There was no significant difference in the incidence of nausea between the groups. Metoclopramide, the rescue antiemetric, was demanded by 38%, 34% and 17% of patients receiving saline, droperidol and ondansetron, respectively (ondansetron vs droperidol P < 0.05).