The Effect of Anesthesia on Potential Cerebrospinal Fluid (CSF) and Serum Markers of Alzheimer's Disease.

Alzheimer's disease represents a growing public health problem in developed countries. Although the pathogenesis is not clearly defined, accumulation of extracellular amyloid, neurofibrillary tangles and neuronal loss are the hallmarks of Alzheimer's disease. The effect of anesthetic agents on changes in these proteins in humans is not well characterized, but in-vitro evidence suggests that anesthetic agents can accelerate potential pathogenic mechanisms, such as increasing amyloid formation or rates of apoptosis in cultured cells and increasing amyloid levels in mice. Human data on the effect of anesthetic agents on amyloid and tau proteins is limited to a small series of 11 patients and showed a significant increase in tau levels after exposure to anesthetics. In this study the investigators propose to measure CSF and serum biomarkers in a population of patients with normal CSF dynamics, who are undergoing surgery for repair of a thoracoabdominal aneurysm. The investigators will also obtain preliminary data on whether changes in CSF levels of these proteins are associated with postoperative delirium or cognitive change.