Efficacy of opioid-free anesthesia in reducing postoperative adverse events for thoracoscopic pulmonary surgery: a randomized controlled trial.

BACKGROUND: This study compared the effects of opiate-free anesthesia (OFA) using thoracic paravertebral block combined with dexmedetomidine versus traditional anesthesia with sufentanil and remifentanil on postoperative adverse reactions after thoracoscopic lung surgery. METHODS: A prospective, randomized, double-blind trial included 97 patients(49 in OFA group,48 in S group).All received preoperative thoracic paravertebral block.The primary outcome was the incidence of opioid-related adverse reactions (hypoxemia, hypotension, nausea, vomiting, dizziness) at 2,4,6,24,and 48 h postoperatively.Secondary outcomes included intraoperative events, pain scores, opioid consumption, time to first flatus/defecation, and cardiovascular complications. RESULTS: At 2 h postoperatively, hypotension incidence was lower in the OFA group(8.2%vs 33.3%,P = 0.002),with fewer overall adverse reactions (18.4%vs 39.6%,P = 0.018).At 24 h, PONV was 0%in OFA vs. 10.4%in S group(P = 0.027),dizziness was 8.2%vs 22.9%(P = 0.041),and overall adverse reactions were 10.2%vs 27.1%(P = 0.029).OFA had fewer vasopressor applications (P < 0.001), lower 24-hour opioid use (P = 0.033), fewer analgesic pump presses(P = 0.004),and earlier first feeding (9.5 ± 3.8 h vs. 11.4 ± 4.7 h, P = 0.035). CONCLUSION: OFA significantly reduced opioid-related adverse reactions, decreased vasopressor and opioid use, and improved recovery.However, the single-center, small-sample design limits generalizability, and multicenter validation is needed. TRIAL REGISTRATION: This randomized controlled trial was registered on clinicaltrials.gov (ID: NCT04507165; URL: https://clinicaltrials.gov/study/NCT04507165 , 11/08/2020).