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.

CONCLUSIONS

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