Prophylaxis of Postoperative Nausea and Vomiting after Cardiac Surgery in High-risk Patients: A Randomized Controlled Study

CONTEXT: The role of prophylaxis for postoperative nausea and vomiting (PONV) in cardiac surgery is under debate. AIMS: To study the risk factors for PONV after cardiac surgery and the role of betamethasone with or without droperidol for its prevention. SETTING AND DESIGN: Randomized open-label controlled study comparing standard care with PONV prophylaxis from February to November 2016. METHODS: Five hundred and two patients with planned nonemergent cardiac surgery were included. INTERVENTIONS: In the intervention arm, PONV prophylaxis (4 mg betamethasone with/without 0.625 mg droperidol) was administered in high-risk patients (two or more risk factors). Patients in the control arm were treated as per routine hospital practices. RESULTS: Female sex, past history of PONV, and migraines were associated with a significantly increased risk of PONV, while motion sickness, smoking status, and volatile anesthetics were not. Pain and treatment with nefopam or ketoprofen were associated with an increased risk of PONV. PONV was less frequent in the active arm compared to controls (45.5% vs. 54.0%, P = 0.063; visual analogic scale 10.9 vs. 15.3 mm, P = 0.043). Among the 180 patients (35.6%) with ≥2 risk factors, prophylaxis was associated with reduced PONV (intention-to-treat: 46.8% vs. 67.8%, P = 0.0061; per-protocol: 39.2% vs. 69%, P = 0.0002). In multivariate analysis, prophylaxis was independently associated with PONV (odds ratio [OR]: 0.324, 95% confidence interval: 0.167-0.629, P = 0.0009), as were female sex, past history of PONV, and migraines (OR: 3.027, 3.031, and 2.160 respectively). No drug-related side effects were reported. CONCLUSION: Betamethasone with/without droperidol was effective in decreasing PONV in high risk cardiac surgical patients without any side effect.