Effects of Intravenous Lidocaine Infusion on Stress Response in Patients Undergoing Abdominal Surgery During Perioperative Anesthesia and Its Correlation With Serum Orphanin FQ (N/OFQ)

We hypothesize that intravenous injection of lidocaine during the perioperative period can reduce expression of endogenous opioid peptides, which in turn can decrease secretion of IL-6 and TNF-α, ultimately leading to a reduction in perioperative stress response. This randomized controlled trial will be conducted at the Second Hospital of Shanxi Medical University in China, with the aim of observing changes in stress-related indicators (blood pressure, heart rate, heart rate variability, IL-6, TNF-α, as well as Serum N/OFQ ) between patients undergoing abdominal surgery under total intravenous general anesthesia with and without lidocaine injection. Lidocaine will be administered as a loading dose during anesthesia induction and continued via infusion until the end of anesthesia maintenance, with appropriate depth of anesthesia or BIS readings utilized for monitoring anesthesia depth. Routine monitoring parameters, including blood pressure, heart rate, SpO2, and electrocardiogram, will be recorded and analyzed. Blood samples will be collected 30 minutes before anesthesia induction, 1 minute after tracheal intubation, and at the end of surgery. The use of lidocaine will be evaluated for its impact on perioperative stress response in patients undergoing abdominal surgery, with the relationship to changes in levels of endogenous opioid peptides explored.