Safety and Efficacy of Alfentanil Compared to Sufentanil in Target- Controlled Infusion During Flexible Bronchoscopy: A Randomized Controlled Trial

Background Optimal anesthetic management during flexible bronchoscopy requires balancing sedation, safety, and procedural efficiency. Target-controlled infusion (TCI) systems offer precise drug delivery, but comparative data between opioids remain limited. This study compared the safety and efficacy of alfentanil versus sufentanil target-controlled infusion and conventional alfentanil bolus dosing during flexible bronchoscopy. Methods In this prospective, randomized, double-blind trial, 90 patients scheduled for bronchoscopy were enrolled and 1:1:1 assigned to alfentanil TCI (35 ng/mL, Group A), sufentanil TCI (0.2 ng/mL, Group S), or alfentanil bolus (5 µg/kg, Group M). Primary outcomes included hemodynamic stability and cough frequency. Secondary outcomes encompassed timing, respiratory complications, additional medication requirements, and procedural quality. Results Baseline demographics were well-balanced across groups (all P > 0.05). Cough incidence was significantly lower in both alfentanil groups compared to sufentanil TCI (Group A: median 1 [IQR 1-1.25]; Group M: median 1 [IQR 1–2] versus Group S: median 2 [IQR 1–3]; P = 0.006). Hemodynamic parameters showed time-dependent differences between groups, with significant variations in heart rate and diastolic blood pressure at several time points, though all values remained within clinically acceptable ranges. Induction time was significantly shorter with alfentanil TCI versus other groups (Group A: 2 [2–3] minutes versus Group S and M: 3 [2–4] and 3 [2–3] minutes, respectively; P < 0.001). Awakening time demonstrated marked differences, with alfentanil bolus providing the fastest recovery (Group M: 7.5 [5–10] minutes versus Group A: 10 [8.75-12] minutes versus Group S: 19 [14.25-22] minutes; P < 0.001). No significant differences were observed in respiratory depression rates, additional propofol needs, or bronchoscopist satisfaction scores between groups. Conclusions Alfentanil regimens provided superior cough suppression compared to sufentanil. Alfentanil TCI offered the fastest induction, while bolus dosing enabled the quickest recovery. Both demonstrated favorable safety, supporting alfentanil as the preferred opioid for flexible bronchoscopy, with regimen choice guided by clinical priorities. Trial Registration This trial was retrospectively registered in the Chinese Clinical Trial Registry (ChiCTR2400089901) on September 19, 2024.