Pharmacological Management of Postoperative Nausea and Vomiting in Abdominal Surgery: Efficacy of Antiemetic Protocols

Background: Postoperative nausea and vomiting (PONV) are frequent and distressing complications following abdominal surgery, affecting up to seventy percent of high-risk patients. Despite multiple antiemetic options, optimal prophylaxis remains undefined in many settings. Objective: To compare the efficacy of three pharmacologic antiemetic regimens in preventing PONV in adults undergoing elective abdominal surgery. Methods: In this prospective study at Lahore General Hospital (January–December 2024), sixty patients aged 18–65 years were randomized into three groups (n=20 each). Group A received dexamethasone (8 mg) and ondansetron (4 mg) IV at induction. Group B received dexamethasone (8 mg) and palonosetron (0.075 mg) IV at induction. Group C received aprepitant (40 mg PO) two hours preoperatively plus dexamethasone (8 mg) and ondansetron (4 mg) IV at induction. PONV incidence, severity, vomiting episodes, and rescue antiemetic use were recorded for 24 hours postoperatively. Data were analyzed using one-way ANOVA and Chi-square tests with p < 0.05. Results: Baseline characteristics including mean age (40.6 ± 12.4 yr), BMI (25.7 ± 4.2 kg/m²), gender distribution, smoking status, and Apfel scores were comparable across groups. Group C achieved the highest rate of no PONV (55%) and lowest rescue antiemetic requirement (5%), significantly outperforming Group A (25% none; 35% rescue; p < 0.01) and Group B (45% none; 20% rescue; p < 0.05). Severe nausea occurred in 10% of Group A, none in Group B, and 5% in Group C. Mean vomiting episodes were similar across groups. No adverse events related to antiemetic therapy occurred. Conclusion: A multimodal regimen of aprepitant, ondansetron, and dexamethasone provides superior PONV prophylaxis compared to dual-agent protocols in elective abdominal surgery patients. Palonosetron plus dexamethasone also showed substantial efficacy and could serve as an alternative.