Role of Intraoperative Neurophysiological Monitoring in Predicting Postoperative Delirium in Patients Undergoing Carotid Endarterectomy Surgeries.

Introduction: This study aimed to evaluate the diagnostic utility of electroencephalography (EEG) and somatosensory evoked potentials (SSEP) as modalities of intraoperative neurophysiological monitoring (IONM) in predicting postoperative delirium (POD) in patients who underwent carotid endarterectomy (CEA) surgery.

Methods: A total cohort of 425 patients was included in this study. Medical record data were reviewed retrospectively and their documented significant IONM data were analyzed and integrated into the study for each patient. The study cohort was assessed for POD with the Intensive Care Delirium Screening Checklist (ICDSC), and a score of >4 was positive for delirium.

Results: Of the 425 patients who underwent CEA for carotid stenosis, 65 (15.29%) had documented significant IONM changes. Of those 65 patients with significant changes, 16 (24.61%) had POD. On the other hand, of the 360 patients without changes, 31 (8.61%) had POD. Utilizing logistic regression while adjusting for possible confounders, IONM changes were still significantly associated with POD (p value: <0.001; 95% confidence interval (CI): 1.91-7.98; adjusted odds ratio (ORadj): 3.94). Specifically, SSEP changes alone were significantly associated with POD (p value: <0.001; 95% CI: 2.36-11.08; ORadj: 5.15).

Conclusion: Significant IONM changes increase the risk of developing POD in patients undergoing CEA. Despite the low overall risk of POD after CEA in our study, it is imperative to conclude that patients with POD are twice as likely to exhibit IONM changes.