Effect of Perioperative Dexmedetomidine on Chronic Post-Surgical Pain

The goal of this clinical trial is to learn if intranasal dexmedetomidine works to improve sleep quality to treat chronic post-surgical pain (CPSP) in patients undergoing thoracic surgery. It will also learn about the safety of intranasal dexmedetomidine.this clinical trial could include any of the following: Adults aged 18-80 years, Elective surgical patients scheduled for their first thoracoscopic lung resectiony, ASA physical status I-III, and sign the informed consent form. The main questions it aims to answer are: Does intranasal dexmedetomidine reduce the incidence of CPSP in patients undergoing elective thoracic surgery? Does perioperative sleep quality mediates the effect of intranasal dexmedetomidine in improving CPSP outcomes at 3 months post-surgery? What are the safety concerns or medical complications that participants may experience when using intranasal dexmedetomidine perioperatively? Researchers will compare the intervention group receiving intranasal dexmedetomidine to a placebo (a look-alike substance that contains no drug) to assess its impact on perioperative sleep quality and the reduction in CPSP incidence at 3 months post-surgery. Participants will: Take the study drug (intranasal dexmedetomidine) or a placebo (saline) every night between 9:00-9:30 PM, starting the day before surgery and continuing until the day before discharge. After the drug administration, undergo 3 hours of continuous monitoring with ECG and wear a wearable device for ongoing assessment. Cooperate with researchers to assess sedation, pain, sleep, emotional status, medication usage, adverse events, and postoperative recovery quality on postoperative days 1, 2, and 3 You will be contacted by phone at 1, 3, and 6 months by the research team to inquire about sleep, pain, medication use, and overall quality of life after discharge.