The Effects of Anesthesia Depth Monitoring on Postoperative Recovery and Cognitive Functions in the Geriatric Patient Population

Perioperative cognitive decline and delirium occur more frequently in the geriatric population undergoing surgery. International guidelines recommend monitoring anesthesia depth to reduce the risk of postoperative cognitive dysfunction. Anesthesia depth is commonly measured using non-invasive electroencephalography (EEG)-based methods, such as the Bispectral Index (BIS). Previous studies have predominantly utilized processed EEG monitors that generate numerical values for tracking anesthesia depth. However, in this study, anesthesia depth will be monitored using both the standard numerical BIS index and the Density Spectral Array (DSA) mode, an advanced feature of the BIS device. To date, no studies have simultaneously examined BIS and DSA modes in relation to cognitive function and the recovery process. The use of advanced monitoring techniques may serve as a valuable resource for future research, particularly in optimizing anesthetic management for geriatric patients with reduced cognitive reserve. This study aims to evaluate the effects of different intraoperative anesthesia depth monitoring approaches, including hemodynamic monitoring, numerical BIS values, and DSA functions. The primary objective is to determine the optimal anesthesia monitoring strategy that minimizes intraoperative hypotension, burst suppression, and postoperative delirium.