INTRAOPERATIVE ELECTROENCEPHALOGRAPHIC MONITORING AS A PREDICTIVE TOOL FOR POSTOPERATIVE DELIRIUM: AN INTEGRATIVE REVIEW

Introduction: Postoperative delirium is a common neuropsychiatric complication in older adults undergoing intermediate- and high-risk surgery, and it is associated with longer hospital stays, cognitive decline, and increased mortality. Because the intraoperative electroencephalogram records cortical activity directly during anesthesia, it has been investigated as a source of markers capable of identifying vulnerable patients at an early stage. Objective: To analyze the scientific evidence on the use of intraoperative electroencephalographic monitoring as a predictive tool for postoperative delirium in adults and older adults undergoing surgery under general anesthesia. Method: An integrative literature review was conducted, grounded in the principles of evidence-based practice. The review question was structured using the PICo strategy. Searches were carried out in the PubMed/MEDLINE, Embase, Scopus, Web of Science, and LILACS databases. Included studies were characterized in terms of their methodological design and level of evidence, and the findings were subjected to interpretive thematic synthesis. Results: Twelve studies were included. Burst suppression and prolonged electroencephalographic suppression were consistently associated with delirium, and the duration of suppression proved to be the most informative parameter. Reduced frontal alpha power and emergence trajectories lacking spindle activity pointed to lower cerebral reserve. Machine learning models combining clinical and electroencephalographic variables achieved moderate to good discriminative performance. Trials that used the electroencephalogram to guide anesthetic depth, however, did not show a consistent reduction in the incidence of delirium. Conclusion: Intraoperative electroencephalographic monitoring has prognostic value as a marker of cerebral vulnerability, but current evidence does not support its isolated use as a preventive strategy. Its main usefulness appears to lie in risk stratification, combined with preoperative cognitive assessment, validated multivariable prediction models, and multicomponent prevention measures in the postoperative period.