The Effects of Anesthesia on Patients Undergoing Surgery for Repair of a Thoracoabdominal Aneurysm.

Not Applicable

Terminated

Conditions: Aneurysm Stent
Cardiopulmonary Bypass
Abdominal Aneurysm
Thoracic Aneurysm

Brief Summary: 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.

Recruitment & Eligibility

Inclusion Criteria

Exclusion Criteria

Patients with pre-existing delirium
Inability to speak and understand English
Severe hearing impairment, resulting in inability to converse
Pregnancy. Pregnancy status will be assessed using a serum pregnancy test during preoperative evaluation as part of the standard of care.

Arm && Interventions

Group	Intervention	Description
Stent graft repair of thoracoabdominal aneurysms isoflurane	isoflurane	These patients are patients receiving repair of thoracoabdominal aneurysms using stent grafts. These patients will be randomized to receive isoflurane as their primary anesthetic.
Stent graft repair of thoracoabdominal aneurysms propofol	Propofol	These patients are patients receiving repair of thoracoabdominal aneurysms using stent grafts. These patients will be randomized to receive propofol as their primary anesthetic.

Primary Outcome Measures

Name	Time	Method
Changes in Cerebrospinal Fluid (CSF) Levels of Tau	From insertion of spinal drain until removal	Quantitative levels of tau will be measured using ELISA assay technique in pg/ml to compare the differences between the group receiving Propofol and the groups receiving Isoflurane. .
Changes in CSF Levels of Amyloid	From insertion of spinal drain until removal	Quantitative levels of amyloid will be measured using ELISA assay technique in pg/ml to compare the differences between the group receiving Propofol and the groups receiving Isoflurane.

Secondary Outcome Measures

Name	Time	Method
Number of Participants With Delirium as Assessed by the Confusion Assessment Method (CAM)	Immediately after surgery and at 3 and 12 months post-op	Delirium was measured using the Confusion Assessment Method and the Confusion Assessment Method- Intensive Care Unit (CAM-ICU) based upon post-operative location of patient. The patients were divided into to two groups, patients that had an open thoracoabdominal aneurysm repair versus patients that had stenting of their aneurysms. Patients that had stenting of their aneurysms were also randomized to receive either Propofol or Isoflurane as for their anesthetic.