The Effect of the Hyperinsulinemic Normoglycemic Clamp on Myocardial Function and Utilization of Glucose
|Hyperglycemia Aortic Valve Replacement Aortic Stenosis Cardiac Surgery||Other: hyperinsulinemic normoglycemic clamp (HNC) Other: control group|
|Study Design:||Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double Blind (Participant, Outcomes Assessor)
Primary Purpose: Treatment
|Official Title:||The Effect of the Hyperinsulinemic Normoglycemic Clamp on Myocardial Function and Utilization of Glucose|
- Myocardial function [ Time Frame: end of surgery, closure ]Myocardial function measured echocardiographically by global longitudinal systolic strain and strain rate using speckle tracking imaging at end of surgery.
- diastolic function [ Time Frame: end of surgery, closure ]Echocardiographic measures of diastolic function, including transmitral deceleration time (EDT) and velocity of propagation (vp).
- myocardial systolic function [ Time Frame: Day 3 - Day 5, post operative, end of surgery, closure. ]Additional echocardiographic measures of myocardial systolic function, such as myocardial velocities measured by tissue Doppler imaging and left ventricular ejection fraction (LVEF), and postoperative strain and strain rate.
- right ventricular function [ Time Frame: end of surgery, closure ]right ventricular function as assessed by right ventricular longitudinal strain and strain rate
- activation of glucose metabolic pathways [ Time Frame: intraoperative ]assessment of the activation of glycolysis, pyruvate oxidation pathway, and hexosamine biosynthetic pathway.
|Study Start Date:||October 2010|
|Study Completion Date:||December 2013|
|Primary Completion Date:||August 2013 (Final data collection date for primary outcome measure)|
Experimental: hyperinsulinemic normoglycemic clamp (HNC)
Patients will be randomized to receive treatment with HNC during cardiac surgery.
Other: hyperinsulinemic normoglycemic clamp (HNC)
Prior to anesthetic induction, a baseline blood glucose value will be obtained, followed by an insulin infusion of 5 mU.Kg-1.min-1. When blood glucose is <110 mg/dL, a variable continuous infusion of glucose (dextrose 20%) supplemented with potassium (40 mEq/L) and phosphate (30 mmol/L) is administered to preserve normoglycemia (80-110 mg/dL). The glucose infusion is titrated to target glucose levels by checking blood glucose every 5 - 15 min with Accu-Check (Roche Diagnostics, Switzerland) glucose monitor. At sternal closure, insulin infusion is decreased to 1 mU/Kg/min. On admission to the ICU, insulin treatment follows the ICU protocol. The dextrose infusion is slowly weaned off over 2 - 4 hrs maintaining blood glucose > 80 mg/dL. Arterial blood glucose is measured every 30 - 60 min for 2 hrs, then, as stated in ICU protocol.
Placebo Comparator: standard glucose management
Patients will be randomized to receive treatment with standard glucose management during cardiac surgery.
Other: control group
Baseline arterial blood glucose will be obtained before anesthetic induction. Repeat measurements are performed every 30-90 min. Glucose >150 on CPB will receive insulin according to intraoperative protocol. After surgery, insulin is given according to ICU protocol. Target glucose < 180 mg/dL.
Specific Aim #1:To determine whether intraoperative use of HNC affords cardioprotective benefits measured by improved echocardiographic measures of myocardial function, serum markers of cardiomyocyte injury, and hemodynamic indices measured immediately (at end of surgery) and during the short-term (initial hospitalization).
Specific Aim #2 and #3 To determine the mechanism of HNC by laboratory analysis of right atrial tissue.
Specific Aim #2 To determine if HNC decreases flux via HBP and cellular markers of injury.
Specific Aim #3 To determine if HNC augments glucose uptake and utilization.
Please refer to this study by its ClinicalTrials.gov identifier: NCT01187329
|United States, Ohio|
|Cleveland Clinic Foundation|
|Cleveland, Ohio, United States, 44195|
|Principal Investigator:||Andra Duncan, MD||The Cleveland Clinic|