Relationship Between Sleep EEG, Intraoperative EEG and Postoperative Cognitive Dysfunction

The challenge of new recommendations and better adapted practices is pushing to operate patients who are getting older and more fragile. In this context, there is an inevitable increase in the risks associated with care and in particular perioperative neurological complications, of which postoperative cognitive dysfunction (POCD) is the most common. The interest of perioperative cerebral monitoring and in particular electroencephalography (EEG) to reduce neurological and cognitive damage in surgery has been the subject of abundant research and corresponds to a crucial issue. From the literature and preliminary results obtained in our clinical research unit, it appears that there is also a relationship between certain characteristics of the peroperative EEG (signal strength and burst suppression) and the occurrence of postoperative cognitive dysfunction (PCOD). In this context, quantitative analysis of the preoperative sleep EEG and the EEG obtained during general anesthesia could allow the identification of a simple to use biomarker of susceptibility or fragility. To our knowledge, there is no preoperative evaluation strategy using EEG analysis to detect a predisposition to POCD. The main goal of this observational clinical study is to extend the traditional use of per-operative EEG with pre-operative and post-operative sleep EEG for the detection and prediction of early post-operative cognitive dysfunction.