Opioid Free Anesthesia and Its Effects on Clinical Outcomes in Thoracoscopic Surgery: A Clinical Trial Study

Background: Opioids, though central to anesthesia, are associated with adverse effects such as respiratory depression, immunosuppression, postoperative ileus, nausea, delirium, and opioid-induced hyperalgesia, all of which hinder recovery. Thus, implementing opioid-free anesthesia strategies has become a critical and necessary evolution in modern anesthetic practice. Objectives: The present study was designed and implemented with the aim of evaluating opioid-free anesthesia and its effects on clinical outcomes in thoracoscopic surgery. Methods: Sixty patients were randomly assigned to two groups (opioid-free and opioid). All patients in both groups underwent surgery performed by the same surgeon. In the control group, anesthesia was induced with fentanyl (1 - 3 μg/kg), midazolam (0.02 mg/kg), atracurium (0.5 mg/kg), and propofol (1.5 - 2.5 mg/kg), and maintained with isoflurane (up to 1 MAC). In the opioid-free group, fentanyl was replaced with ketamine (0.5 mg/kg), and dexmedetomidine (0.6 μg/kg/h) was added for maintenance alongside isoflurane. Postoperative analgesia in both groups included intravenous acetaminophen for visual analog scale (VAS) > 3, as rescue. Clinical parameters (heart rate, blood pressure, respiratory rate, pruritus, nausea/vomiting) and VAS pain scores were assessed at 0, 2, 4, 6, 8, 12, 18, and 24 hours, and complications were evaluated postoperatively. Results: The opioid-free group showed significantly lower heart rate at 6, 8, and 12 hours postoperatively compared with the opioid group (P < 0.05). VAS pain scores were also significantly lower during recovery and at 2, 12, and 18 hours after surgery. Significant postoperative differences were observed between groups in C-reactive protein (CRP), blood urea nitrogen (BUN), and creatinine levels. Conclusions: The results of this study add to the growing body of evidence supporting the feasibility and safety of opioid-free anesthesia in thoracoscopic surgery.