Intraoperative Dexmedetomidine Use, MMP-8, and Postoperative Delirium After Cardiac Surgery With Cardiopulmonary Bypass

This observational study evaluated the association between intraoperative dexmedetomidine use and postoperative delirium (POD) in adults undergoing cardiac surgery with cardiopulmonary bypass (CPB). The study included two linked clinical components. First, routinely collected clinical data from patients undergoing cardiac surgery with CPB at three campuses of Tongji Hospital between January 2015 and December 2022 were analyzed to evaluate the dexmedetomidine-POD association. Second, perioperative plasma samples and clinical data from a prospective observational cohort enrolled between April 2023 and September 2024 were used to characterize perioperative matrix metalloproteinase-8 (MMP-8) dynamics and their associations with intraoperative dexmedetomidine use and POD. Dexmedetomidine administration was determined by the attending anesthesiologist according to clinical judgment and routine anesthetic practice and was not assigned by the study protocol.