Nausea and vomiting after major arthroplasty with spinal anaesthesia including morphine: a randomised trial of subhypnotic propofol infusion as prophylaxis.

BACKGROUND: Postoperative nausea and vomiting (PONV) following major arthroplasty with spinal anaesthesia and intrathecal morphine is reported in 45-74% of patients. This randomised, double-blind, placebo-controlled trial was undertaken to determine whether a subhypnotic infusion of propofol has a prophylactic antiemetic effect in this patient population.

METHODS: 82 patients undergoing hip or knee replacement under subarachnoid bupivacaine anaesthesia plus morphine 0.25 mg were randomised at the end of surgery to receive either propofol 30 mg x h(-1) or fat emulsion (Intralipid) 3 ml x h(-1) for 20 h postoperatively. Blinded observers recorded episodes of nausea, vomiting and pruritus.

RESULTS: PONV in the intervention group was 40% vs 59% in the controls (P=0.1, not significant). Pruritus occurred in 34%, with a similar rate in both groups.

CONCLUSION: These results suggest that routine use of postoperative, subhypnotic propofol infusion as PONV prophylaxis is not justified in this patient population.