RESUMO
BACKGROUND: Aprepitant is effective in prevention of chemotherapy-induced nausea and vomiting, when administrated with other antiemetics. We compared the effectiveness of aprepitant to ondansetron for prevention of post-operative nausea and vomiting (PONV) in patients who received a patient-controlled analgesia (PCA) containing opioids. METHODS: 198 patients were randomized into two groups. The treatment group was received an aprepitant, 80 mg, and the control group received a placebo. General anesthesia with inhalational anesthetics–N2O was performed, and PCA was supplied, which contained opioids-NSAIDs-ondansetron. The primary end-point was the incidence of PONV for postoperative 48 hours, and the secondary end-point was the changes in the relationship between PONV incidence and risk factors. RESULTS: PONV incidence in the treatment group was lower than in the control group (18.6% [95% CI: 10.8–26.3], 33.3% [95% CI: 23.6–43.1], respectively, P = 0.021). Relative risk of PONV in the control group was 1.80 (95% CI: 1.08–3.00, P = 0.010). PONV scores peaked at around postoperative 6 hours, then gradually decreased in the control group but not in the treatment group, which showed lower values than the control group (P = 0.001), and no changing patterns were observed (P < 0.001). Risk factors analyzed were sex, surgery type, history of motion sickness or PONV, and smoking habits. Their effects of all risk factors except sex were abolished in the treatment group. CONCLUSIONS: Prophylactic aprepitant with ondansetron was more effective than ondansetron-only regimen in preventing PONV after volatile anesthesia with opioid-containing PCA. Aprepitant abolished the effects of most of risk factors, so it could be efficacious in a high-risk PONV group.