Opioid-Free Versus Opioid-Based Anesthesia in Thyroid Surgery

This study will compare opioid-free anesthesia and opioid-based anesthesia in adult euthyroid patients undergoing elective thyroidectomy. Opioid-based anesthesia is commonly used during surgery, but opioids may be associated with adverse effects such as nausea, vomiting, respiratory depression, hyperalgesia, and increased postoperative opioid use. Opioid-free anesthesia uses non-opioid medications as part of a multimodal strategy to provide intraoperative analgesia. The main aim of this prospective randomized study is to evaluate whether opioid-free anesthesia changes the perioperative oxidative stress response compared with opioid-based anesthesia. Oxidative stress will be assessed using serum biomarkers, including native thiol, total thiol, disulfide, total antioxidant status, total oxidant status, and oxidative stress index. Eligible patients will be randomly assigned to receive eit