Effect of Raised CBF During CEA on Cognition in DM Patients

This study is currently recruiting participants. (see Contacts and Locations)
Verified July 2013 by Columbia University
Sponsor:
Information provided by (Responsible Party):
Eric J. Heyer, MD, PhD, Columbia University
ClinicalTrials.gov Identifier:
NCT00597545
First received: January 9, 2008
Last updated: July 29, 2013
Last verified: July 2013
  Purpose

The purpose of this study is to determine if we can reduce the incidence of cognitive dysfunction — difficulty in performing certain pencil-paper, memory, finger dexterity and thinking type of tasks called neuropsychometric tests — in patients with adult onset diabetes mellitus (DM) undergoing surgery on the carotid artery (CEA).

We hypothesize that cognitive dysfunction can be decreased in patients with type II DM by augmenting cerebral blood flow with a shunt during carotid endarterectomy compared to patients with Type II DM who are treated with "conventional" management in which a shunt is placed only if the electroencephalogram (EEG) indicates cerebral ischemia.


Condition Intervention
Carotid Artery Disease
Carotid Artery Stenosis
Diabetes
Cognitive Dysfunction
Procedure: Shunt

Study Type: Interventional
Study Design: Allocation: Randomized
Endpoint Classification: Efficacy Study
Intervention Model: Single Group Assignment
Masking: Double Blind (Subject, Investigator)
Primary Purpose: Prevention
Official Title: Effect of Augmentation of Cerebral Blood Flow on Neuropsychometric Performance After Carotid Endarterectomy in Type II Diabetic Patients

Resource links provided by NLM:


Further study details as provided by Columbia University:

Primary Outcome Measures:
  • Neuropsychometric Changes [ Time Frame: Morning of surgery and post-operatively at 1 day, 1 month, and 6 months ] [ Designated as safety issue: No ]
    Battery of neuropsychometric tests to evaluate a variety of cognitive functions.


Estimated Enrollment: 400
Study Start Date: March 2007
Estimated Study Completion Date: June 2014
Estimated Primary Completion Date: June 2014 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Conventional Shunt
Subjects will receive a shunt only if it is indicated by EEG, "conventional" management.
Procedure: Shunt
We will randomly assign patients to either receive a "shunt" prophylactically if the surgeon determines that it is technically safe, even if conventional management does not indicate it is necessary, or a "shunt" only if it is indicated by EEG, "conventional" management. Subjects in the prophylactic group will receive a shunt even when by standard criteria they would not need to receive one. Randomization will be performed in blocks of four patients each using a randomization table. Using "block" randomization we will increase the probability of an equal number of patients "shunted" or not shunted. The surgeon will be told which group the patient has been randomized into after induction and prior to clamping the carotid artery.
Experimental: Prophylactic Shunt
Subjects in the prophylactic group will receive a shunt even when by standard criteria they would not need to receive one.
Procedure: Shunt
We will randomly assign patients to either receive a "shunt" prophylactically if the surgeon determines that it is technically safe, even if conventional management does not indicate it is necessary, or a "shunt" only if it is indicated by EEG, "conventional" management. Subjects in the prophylactic group will receive a shunt even when by standard criteria they would not need to receive one. Randomization will be performed in blocks of four patients each using a randomization table. Using "block" randomization we will increase the probability of an equal number of patients "shunted" or not shunted. The surgeon will be told which group the patient has been randomized into after induction and prior to clamping the carotid artery.

  Hide Detailed Description

Detailed Description:

Based on previous clinical studies, we have found that patients with diabetes mellitus (DM) who are having carotid endarterectomy (CEA) have a four-fold higher incidence of cognitive dysfunction, 1 day and 1 month after surgery, than a control group of elderly diabetic patients having spine surgery.

We hypothesize that this increased incidence is due to sub-cortical ischemia associated with the clamping of the ipsilateral carotid artery, because intra-operatively we rarely see EEG changes, or a significant number of emboli upon clamping or unclamping the carotid artery, or new cortical lesions of ischemia by MRI after surgery. In order to decrease cognitive dysfunction in patients with DM, we propose to randomize them to either i) have a shunt placed across the surgical site assuming it is surgically feasible or ii) be treated by "conventional" management during which time a shunt is placed only in the unlikely event of significant cortical ischemia determined by EEG, which occurs in about 5% of all cases.

The purpose of this study is to determine if patients with adult-onset diabetes mellitus having the surgical procedure called carotid endarterectomy benefit from increasing blood flow to the brain with a "shunt". A "shunt" is a tube inserted below and above the surgical area at the time when the carotid artery is clamped to allow the surgeon to work in a bloodless field and to supplement blood flow to the brain. Benefit is measured after surgery by comparing performance on a battery of cognitive tests, which test your ability to perform pencil-paper, memory and finger dexterity tests, to performance before surgery.

Patients in the shunt group whom the surgeon at the time of surgical exposure considers too technically difficult to shunt, will not have a shunt inserted but will be treated statistically as if they were shunted (intention to treat). Follow-up evaluations will be performed 1 day, and 1 and 6 months after surgery so that the long-term effect of shunting can be evaluated.

Cerebral injury will be determined in two 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 1 day before, and 1 day, and 1 and 6 months after surgery. Those coming into the hospital on the day of surgery, "Same Day", will be evaluated on the day of surgery. They will be evaluated 1 day, and 1 and 6 months after surgery.

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 gauge their mood with a series called the Wong/Baker Faces Rating scale. Patients having spine surgery may have significant pain before surgery which might impair their performance.

We will also 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 14Item 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.

Second, peripheral serum samples will be drawn before induction, before crossclamping the carotid artery, 15 minutes after crossclamping the carotid artery and 24 hours after surgery.

Since the purpose of this study is to determine if a change in "conventional" management will improve patient's ability to perform our battery of neuropsychometric tests, we will randomly assign patients to either receive a "shunt" prophylactically if the surgeon determines that it is technically safe, even if conventional management does not indicate its necessary, or a "shunt" only if it is indicated by EEG, "conventional" management. Subjects in the prophylactic group will receive a shunt even when by standard criteria they would not need to receive one. Randomization will be performed in blocks of four patients each using a randomization table. Using "block" randomization we will increase the probability of an equal number of patients "shunted" or not shunted. The surgeon will be told which group the patient has been randomized into after induction and prior to clamping the carotid artery.

  Eligibility

Ages Eligible for Study:   18 Years and older
Genders Eligible for Study:   Both
Accepts Healthy Volunteers:   No
Criteria

Inclusion Criteria:

  • ability to speak English
  • no history of permanent neurological impairment, Axis I psychiatric diagnosis or drug abuse.
  • scheduled for elective carotid endarterectomy for treatment of carotid artery stenosis.
  • diagnosed with diabetes mellitus or HbA1c value greater than 10%

Exclusion Criteria:

  • younger than 18 yrs.
  Contacts and Locations
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

Please refer to this study by its ClinicalTrials.gov identifier: NCT00597545

Contacts
Contact: Kaitlin A Mallon, BA 212-305-8949 km2954@cumc.columbia.edu
Contact: Eric Heyer, M.D., Ph.D. 212-305-9072 ejh3@columbia.edu

Locations
United States, New York
Columbia University, Department of Anesthesiology Recruiting
New York, New York, United States, 10032
Sponsors and Collaborators
Columbia University
Investigators
Principal Investigator: Eric J Heyer, M.D., Ph.D. Columbia University
  More Information

Publications:
Responsible Party: Eric J. Heyer, MD, PhD, Professor of Clinical, Department of Anethesiology Clinical Operations, Columbia University
ClinicalTrials.gov Identifier: NCT00597545     History of Changes
Other Study ID Numbers: AAAC3837
Study First Received: January 9, 2008
Last Updated: July 29, 2013
Health Authority: United States: Institutional Review Board

Keywords provided by Columbia University:
carotid endarterectomy
Neuropsychological tests
Stroke
Transient ischemia
Hypoperfusion
Ischemia

Additional relevant MeSH terms:
Cognition Disorders
Carotid Artery Diseases
Carotid Stenosis
Delirium, Dementia, Amnestic, Cognitive Disorders
Mental Disorders
Cerebrovascular Disorders
Brain Diseases
Central Nervous System Diseases
Nervous System Diseases
Vascular Diseases
Cardiovascular Diseases
Arterial Occlusive Diseases

ClinicalTrials.gov processed this record on September 16, 2014