Assessing Brain Frailty; The Association Between Pre, Intra and Post-operative Electrophysiological Markers and Postoperative Cognitive Dysfunction

As the population ages and medical progress is made, many elderly patients that previously would not have been candidates for surgery are now undergoing operations. In this group of older patients, brain dysfunction after anesthesia and surgery, naming post-operative cognitive dysfunction, is well known. Post-operative cognitive dysfunction (POCD) is a term used to describe subtle changes in cognition, such as memory and executive function. The most commonly seen problems are memory impairment and impaired performance on intellectual tasks. In severe cases, it can lead to inability to perform daily living functions. It was previously found that the presence of cognitive dysfunction 3 months after non-cardiac surgery was associated with increased mortality. The mechanisms leading to cognitive impairment after anesthesia and surgery are not yet fully clear. The risk factors are related to patient characteristics, type of operation and anesthetic management. The investigators have recently shown that using different electrophysiological markers, they can monitor attention and perception which might be associated with brain frailty and brain injury. The aims of this proof of concept study are: (i) to find-out whether attention processes might be in association with brain frailty. (ii) to find our whether brain injury which is expressed by interhemispheric synchronization is is associated with POCD; (iii) to find out whether the level of anesthesia, as measured electrophysiological by perception might be linked primary to POCD.