This randomized, double-blind, controlled clinical trial evaluates whether adding dexmedetomidine to an oliceridine-based patient-controlled intravenous analgesia (PCIA) regimen can improve postoperative pain control and tolerability after video-assisted thoracoscopic lobectomy in adults with high nicotine dependence (Fagerström score ≥6). A total of 102 participants are allocated 1:1:1 into three groups: (1) oliceridine PCIA alone; (2) oliceridine PCIA plus low-dose dexmedetomidine (0.05 μg/kg/h); or (3) oliceridine PCIA plus standard-dose dexmedetomidine (0.1 μg/kg/h). PCIA solutions are prepared to 100 mL, delivered with a basal rate of 2 mL/h, a 0.5-mL bolus, and a 15-minute lockout; a small loading dose is given near the end of surgery. Tramadol is permitted as rescue analgesia per protocol.
The primary objectives are to compare postoperative pain intensity at rest and with movement and overall patient satisfaction within 48-72 hours after surgery. Secondary objectives include sedation level, negative affect (anxiety/depression) scores, comfort and functional recovery scales, effective PCIA presses, rescue analgesic use, and safety outcomes (nausea/vomiting, shivering, bradycardia, hypotension, hypoxemia, and respiratory depression). Outcomes are assessed at approximately 4, 8, 12, 24, and 48 hours after surgery, with a satisfaction survey at 72 hours.
The investigators hypothesize that oliceridine PCIA combined with dexmedetomidine-particularly at 0.1 μg/kg/h-will reduce movement-related pain, decrease rescue opioid needs and PCIA presses, improve mood and comfort scores, and maintain acceptable hemodynamic and respiratory safety compared with oliceridine alone.