Perioperative Butorphanol as a Multimodal Analgesic Strategy to Reduces Emergence Agitation and Attenuates Systemic Inflammation in Elderly Patients Undergoing Transurethral Resection of the Prostate: A Pragmatic Randomized Controlled Trial

Abstract Background Emergence agitation (EA) is a common complication after general anesthesia in elderly patients undergoing transurethral resection of the prostate (TURP), a procedure associated with multiple risk factors for EA. Butorphanol, a κ‑opioid receptor agonist and µ‑antagonist, may reduce EA through its sedative, analgesic, and anti‑inflammatory properties. This randomized controlled trial evaluated the effect of perioperative butorphanol on EA incidence and explored its impact on postoperative pain, sleep quality, delirium, and systemic inflammation. Methods Seventy elderly patients (aged 65–80 years, ASA I - III) scheduled for elective TURP were randomized 1:1 to receive either butorphanol (Group T, 0.15 mg/kg at induction, plus 0.15 mg/kg in postoperative analgesia) or sufentanil (Group C, 0.5 µg/kg at induction, plus 1.5 µg/kg in analgesia). The primary outcome was the incidence and scores of EA at extubation (Richmond Agitation-Sedation Scale [RASS] score ≥ 1). Secondary outcomes included clinical assessments (pain via NRS, sleep via PSQI, delirium via 3D‑CAM), recovery parameters (BIS, time to extubation, bladder irrigation durationand PCA consumption), and postoperative safety metrics (hemodynamic parameters and adverse events). Intraoperative anesthetic consumption and the total dosages of sufentanil or butorphanol were also recorded; these were standardized and compared using morphine equivalent units (10 µg sufentanil = 10 mg morphine; 2 mg butorphanol = 10 mg morphine). Results Baseline characteristics were comparable. Butorphanol significantly reduced EA incidence (5.71% vs. 31.43%, P = 0.006) and RASS scores ( P = 0.001). Pain scores at extubation were lower in Group T ( P < 0.001), and sleep quality was improved on postoperative days 2 and 3 ( P < 0.05). The time from drug discontinuation to extubation was longer in Group T than in Group C, while both the BIS value at extubation and the morphine equivalent dose were lower in Group T than in Group C ( P < 0.05). Serum TNF‑α and IL‑10 levels at extubation were significantly lower in Group T ( P < 0.05). No differences were observed in postoperative delirium incidence, adverse events, or hemodynamic profiles. Conclusion Perioperative butorphanol reduces EA, improves immediate postoperative analgesia and sleep quality, and attenuates systemic inflammation in elderly patients undergoing TURP, supporting its use as a safe and effective component of multimodal anesthesia in this high‑risk population. This offers a practical, opioid-sparing alternative to conventional µ-opioid dominated regimens, directly facilitating individualized patient management in urological anesthesia practice. Trial registration Chinese Clinical Trial Registry ChiCTR2500114145, registered retrospectively on December 08, 2025, http://www.chictr.org.cn/.