Cerebral oximetry-guided anaesthesia and postoperative delirium in elderly patients undergoing off-pump coronary artery bypass grafting: a randomized controlled trial

While cerebral oximetry monitoring has been reported to reduce neurological dysfunction and hospital stay after cardiac surgery, its effect on postoperative delirium (POD) during off-pump coronary artery bypass grafting (CABG) remains underexplored. This study examines whether using cerebral oximetry to guide anaesthesia can reduce POD in patients aged ≥ 65 years undergoing off-pump CABG. This single-center, randomized trial enrolled 200 patients scheduled for off-pump CABG. Participants were randomly assigned (1:1) to either the intervention or control group using sealed envelopes prior to anaesthesia. In the intervention group, cerebral oxygen saturation was continuously monitored by cerebral oximetry. A desaturation event (a drop > 20% from baseline or an absolute regional cerebral oxygen saturation 70 years) in the intervention group compared to the controls 5/47 (10.6%) vs. 11/31 (35.5%); P = 0.011, suggesting a possible interaction between cerebral oximetry-guided anaesthesia and advanced age. ICU and hospital stays were also markedly shorter in the intervention group. Cerebral oximetry-guided anaesthesia did not significantly reduce POD in patients aged ≥ 65 years undergoing off-pump CABG; exploratory analyses suggested a numeric reduction in those > 70 years. However, this observation requires prospective validation in a larger, adequately powered trial. ChiCTR2300068537 (Chinese Clinical Trial Registry), registered 22/02/2023.