Cost-effectiveness of three combinations of antiemetics in the prevention of postoperative nausea and vomiting

Background. This study compares the cost-effectiveness of threecombinations of antiemetics in the prevention of postoperativenausea and vomiting (PONV). Methods. We conducted a prospective, double-blind study. NinetyASA I–II females, 18–65 yr, undergoing general anaesthesiafor major gynaecological surgery, with standardized postoperativeanalgesia (intrathecal 0.2 mg plus i.v. PCA morphine), wererandomly assigned to receive: ondansetron 4 mg plus droperidol1.25 mg after induction and droperidol 1.25 mg 12 h later (Group1); dexamethasone 8 mg plus droperidol 1.25 mg after inductionand droperidol 1.25 mg 12 h later (Group 2); ondansetron 4 mgplus dexamethasone 8 mg after induction and placebo 12 h later(Group 3). A decision analysis tree was used to divide eachgroup into nine mutually exclusive subgroups, depending on theincidence of PONV, need for rescue therapy, side effects andtheir treatment. Direct cost and probabilities were calculatedfor each subgroup, then a cost-effectiveness analysis was conductedfrom the hospital point of view. Results. Groups 1 and 3 were more effective (80 and 70%) thanGroup 2 (40%, P=0.004) in preventing PONV but also more expensive.Compared with Group 2, the incremental cost per extra patientwithout PONV was €6.99 (95% CI, –1.26 to 36.57) forGroup 1 and €13.55 (95% CI, 0.89–132.90) for Group3. Conclusion. Ondansetron+droperidol is cheaper and at least aseffective as ondansetron+ dexamethasone, and it is more effectivethan dexamethasone+droperidol with a reasonable extra cost. Br J Anaesth 2003; 91: 589–92