Neurologic and Neuropsychometric Outcome in Patients Undergoing Carotid Endarterectomy

Cerebral injury will be determined in four ways. First, all patients will be evaluated using a battery of neuropsychometric tests before and after surgery. Patients admitted to the Irving Clinical Research Center (CRC) will have their tests one day before, one day after surgery and at 1 month. Those coming into the hospital on the day of surgery, "Same Day", will be evaluated on the day of surgery, one day after and at the 1 month follow up. Preoperative neurological and neuropsychological evaluation will be performed. The neuropsychometric tests are not intended to be diagnostic of specific neuropsychiatric disorders, but rather are designed to demonstrate general neuropsychological pathology. These tests can be divided into four types: (1) an evaluation of language, (2) an evaluation of speed of mental processing, (3) an evaluation of ability to learn using a list of words, and (4) an evaluation of visual perception requiring a patient to copy a complex figure. Before the battery is administered we will assess each patient's level of pain while sitting and standing using a 10 point Visual Analog Scale and then gauge their mood with a series called the Wong/Baker Faces Rating scale.

We will be measuring Quality of Life (QOL) in all enrolled patients. This will be done using two well-known examinations (Telephone Interview for Cognitive Status (TICS) and Centers for Disease Control and Prevention Health-Related Quality of Life 14 Item Measure (CDC HRQOL14)) and a series of questions investigating how well patients are able to perform activities of daily living (ADLs) and instrumental activities of daily living (IADLs). These tests will be given at two time points, once before the surgery and then one month after surgery. We will look for changes in quality of life that may correlate with neuropsychometric test performance.

Peripheral serum samples will be drawn before induction, before cross-clamping the carotid artery, 15 minutes after cross-clamping the carotid artery and 24 hours after surgery. These samples will be analyzed for four different sets of markers of cerebral injury, one gene and two markers of systemic inflammation. Serum levels of neuron specific enolase (NSE) and protein S100B, a neuronal enzyme and glial cell component respectively, markers of cell injury will demonstrate cerebral injury

Patients will undergo intraoperative TCD (Transcranial Doppler) The TCD examination will assess the brain's ability to increase cerebral blood flow in response to a pharmacological challenge (CO2 inhalation). TCD measures the degree of cerebral vasodilation, identified as an increase in flow velocity on TCD. This "cerebrovascular reserve" we hypothesize will be able to predict performance on postoperative neuropsychometric tests