Effect of dexamethasone on postoperative emesis and pain

In this double-blind, randomized, placebo-controlled study, we have evaluated the effect of preoperative administration of dexamethasone on postoperative vomiting and pain in 60 women undergoing general anaesthesia for major gynaecological surgery. Dexamethasone 10 mg (group D) or saline (group S) was administered i.v. in a double-blind manner during induction of anaesthesia. Postoperative pain relief was controlled with bolus doses of morphine using an i.v. patient-controlled analgesia device, and patients were assessed for incidence of vomiting, sedation score, verbal pain rating score, time to first morphine demand and morphine consumption at 4, 8, 12 and 24 h after surgery. Six patients in group D and 19 in group S experienced vomiting at least once within the 24-h postoperative period; dexamethasone was effective in reducing the overall incidence of vomiting from 63.3% to 20.0% (P < 0.01). Other variables were similar between the groups, and the influence of dexamethasone on postoperative pain was minimal.