Clinical Research Directory

Inclusion Criteria: 1. Age 18-65 years. 2. Scheduled for a range of surgeries under general anesthesia, including both minimally invasive procedures (such as video-assisted thoracoscopic surgery and laparoscopy) and open surgeries (such as thoracotomy, laparotomy, spinal surgery, total joint replacement, and mastectomy). 3. Capacity to comprehend the study procedures and assessment scales, and communicate effectively with research staff. 4）Classified as American Society of Anesthesiologists (ASA) physical status I, II, or III. 5\) Willingness to participate voluntarily and provide written informed consent. Exclusion Criteria: 1. Known hypersensitivity to dexamethasone or its excipients. 2. Systemic glucocorticoid therapy within 3 months prior to enrolment. 3. History of severe cardiovascular disease, hepatic or renal failure, or systemic rheumatic disease (e.g., rheumatoid arthritis, ankylosing spondylitis, systemic lupus erythematosus). 4. Coexisting chronic pain at enrolment. 5. Uncontrolled diabetes mellitus or active systemic infection. 6. Use of any systemic or topical analgesics within 48 hours prior to surgery. 7. Significant cognitive impairment or severe psychiatric disorder. 8. Pregnancy or lactation.