Abstract
OBJECTIVES: Interleukin-6 (IL-6) and neurofilament light chain (NFL) are predictive biomarkers of postoperative delirium in patients undergoing cardiac surgery. This study was designed to compare postoperative changes in IL-6 and NFL between patients receiving multimodal general anesthesia (MMGA) guided by electroencephalography (EEG) versus standard-of-care anesthesia.
DESIGN: Randomized, controlled, investigator-blinded clinical trial.
SETTING: A single-center, tertiary referral hospital.
PARTICIPANTS: Adults ≥60 years old undergoing coronary artery bypass grafting, valve, or combined procedures.
INTERVENTIONS: MMGA included intraoperative EEG monitoring, total intravenous anesthesia with propofol, remifentanil, ketamine, dexmedetomidine, pecto-intercostal fascial block, and postoperative pecto-intercostal fascial block. Controls received inhaled anesthetics and intravenous fentanyl, without EEG guidance.
MEASUREMENTS AND MAIN RESULTS: IL-6 and NFL were measured at baseline, postoperative day 1, and postoperative day 2. EEG was recorded intraoperatively and postoperatively. Cognition was assessed using the Confusion Assessment Method and Montreal Cognitive Assessment up to 6 months. No significant differences were observed in IL-6 or NFL levels at any time point. Delirium incidence and long-term cognitive dysfunction were also similar. However, burst suppression duration was significantly longer in the MMGA group (mean = 4.83 minutes, standard deviation = 3.47) versus controls (mean = 1.68 minutes, standard deviation = 2.2), particularly during and after cardiopulmonary bypass in male patients.
CONCLUSIONS: MMGA did not reduce postoperative IL-6 or NFL levels, nor did it improve neurocognitive outcomes, compared with standard of care. The higher burst suppression in the MMGA group underscores the need for structured EEG education among cardiac anesthesiologists. Future studies should explore other EEG metrics and multimodal strategies for perioperative brain protection.