Cognitive Outcome in Patients with Asymptomatic Carotid Artery Disease Undergoing Off-Pump Coronary Artery Bypass Graft Surgery with or without Near Infrared Spectroscopy Monitoring: A Randomized Study

Aim: To assess the effect of NIRS monitoring on the cognitive outcome of asymptomatic carotid artery disease patients undergoing off-pump coronary artery bypass grafting. Methods: This randomized controlled trial was carried out at Sir Ganga Ram Hospital, New Delhi, among 50 asymptomatic carotid artery disease patients undergoing OPCAB. Fifty patients were randomized to either an NIRS monitored group or a control group to receive standard monitoring. Cognitive performance was measured with the MOCA score at preoperative, 24 hours, and 6 days after the operation. Duration of ICU stay was also documented and examined through SPSS software. Results: Both groups had a decrease in MOCA scores at 24 hours post-surgery, with partial recovery by day 6. The NIRS group had a slightly lower percentage change in MOCA scores than the control group, but without statistical significance. There was no significant difference in ICU stay between the groups. Overall, NIRS monitoring revealed a trend toward improved cognitive outcomes, although without statistical significance. Conclusion: Near Infrared Spectroscopy did not demonstrate statistically significant cognitive protection, trends did suggest slightly better cognitive preservation in the NIRS group. The study provides evidence for the viability of NIRS as an adjunct to monitoring, though further studies with larger samples might be required to determine its efficacy.