Postoperative Cognitive Decline | Biomedgrid

Post-operative cognitive decline (POCD), described many years ago [1], remains a challenge for all physicians who care for elderly patients. A lot of work has been done in this area but investigators need to be mindful about incorporating some basic precepts into their research protocols. While central nervous system dysfunction after surgery and anesthesia has been described to occur, especially in older adults, it is important to bear in mind that, as Silverstein and colleagues [2] point out, any illness requiring hospitalization may be associated with cognitive decline. This introduces the possibility that cognitive decline occurs as a concomitant of generalized illness rather than being causally related to surgery and anaesthesia and speaks to the need for not only age-matched controls but also disease-matched and hospitalization-matched clinical cohorts, as well. Another confounder of the correlation between POCD and mortality reported by Monk and colleagues 3] is the observation made by a number of investigators that cognitive decline itself increases the risk of mortality in older adults [4,5]. As suggested by Newman and colleagues [6], the very term POCD as a binary definition of what may be, in reality, a continuous process may require modification to reflect the necessity of examining cognitive change as a continuum that marches through discrete events such as surgery and anesthesia. This will necessarily influence the methodology by which changes in test performance are analyzed.