Alfentanil May Reduce Early Postoperative Nausea and Vomiting in Moderate-to-High Risk Patients Undergoing Gastrointestinal Endoscopy: A Prospective Double-Blind Randomized Study

Objective: This trial aimed to compare the effects of alfentanil and sufentanil on postoperative nausea and vomiting (PONV) in patients at moderate-to-high risk undergoing sedated gastrointestinal endoscopy. Methods: Two hundred and eighteen patients were randomized to receive either alfentanil (6.7 µg/kg) or sufentanil (0.1 µg/kg) combined with propofol. The primary outcome was the incidence of PONV within 24 hours postoperatively. Other outcomes included PONV in the post-anesthesia care unit (PACU) and at 48 hours, hemodynamic profiles, induction and recovery times, propofol consumption, and other adverse events. Results: The 24-hour PONV incidence did not differ significantly between groups (0.95% vs. 3.85%, p=0.21). However, during the PACU stay, the alfentanil group had a significantly lower incidence of PONV (0.95% vs. 7.69%, p=0.02) and lower PONV scores (p=0.02). Alfentanil also resulted in a significantly shorter induction time (p<0.01) and more stable intraoperative hemodynamics. The total propofol dose, examination duration, PACU discharge time, and incidence of other adverse events were comparable between groups. Conclusion: For patients at moderate-to-high risk of PONV undergoing sedated endoscopy, alfentanil may associate with a significant reduction in early PONV and faster induction compared to sufentanil, without increasing propofol requirements or other clinical risks. Although the 24-hour PONV risk appeared similar, the improvement in early recovery quality suggests that alfentanil may be a favorable option for efficient sedation. These findings are preliminary and warrant confirmation in larger trials.