Project Description Narrative:
Postoperative cognitive dysfunction (POCD) is defined as a functional impairment of the nervous system, including executive function, psychomotor speed, and/or visuospatial abstraction (all of which are sub-domains of visual attentional control) in patients after surgery/anesthesia. The incidence of POCD has been observed in between 16-59% of patients at seven days post-op, and 12-34% at 12 weeks post-op, although the optimal timing of diagnosis is not known. Cognitive dysfunction after surgery and anesthesia has been recognized for decades, but understanding of the underlying neural mechanisms and which patients are at risk for this complication is still largely unknown. Data from the National Institutes of Health show that approximately 60,000 people have surgery under general anesthesia in the United States each day; thus, over 1,000 such procedures are being performed in Wisconsin on a daily basis. Published rates then suggest that a minimum of 50,000 cases of POCD are present in Wisconsin each year making this a highly impactful negative health consequence of surgical procedures in our state that must be addressed.
Central nervous system neuroinflammation triggered by peripheral surgical trauma, such as cardiac surgery, has been hypothesized as a potential cause of POCD and much research in the setting of cardiac surgery and cardiopulmonary bypass has been performed. However, similar rates of POCD have been noted in both cardiac and noncardiac surgery, suggesting that the root cause is likely to be anesthesia. Advanced age has consistently been identified as a risk factor for the development of POCD; thus, this project focuses on individuals at least 60 years of age.
The researchers’ long-term goal is to identify the constellation of behavioral and brain-based markers of POCD in order to develop auxiliary therapies that will help to ameliorate the deleterious cognitive effects of general anesthesia. The overall objectives for this project, which are the next steps toward attainment of the team’s long-term goal, are to identify the precise attentional sub-processes that are compromised by anesthesia-induced POCD and measure the short-term timing of POCD attention symptoms in the initial month after surgery.