Effect of Preoperative Oral Carbohydrates on Postoperative Insulin Resistance in Patients Undergoing OPCAB(Off- Pump Coronary Artery Bypass Surgery)

Study Overview
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Brief Summary
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Surgical stress creates a state of insulin resistance which has been related to increased postoperative complications. Fasting before surgery induces a catabolic state that contributes to the development of insulin resistance. The aim of this study is to evaluate the effect of preoperative oral carbohydrates on postoperative insulin resistance in patients undergoing OPCAB (off-pump coronary artery bypass surgery). Sixty patients, aged 20 to 79 years, scheduled for OPCAB will be divided into carbohydrate (n=30) and control (n=30) groups. Randomly selected patients of the carbohydrate group are given 400ml of 12.8 g/100 ml carbohydrate beverage in the evening before surgery and in the morning of the operation day (3 hours before their scheduled operation). In contrast, patients in the control group consume no food or drink after midnight before their surgery. The primary endpoints are postoperative insulin resistance measured by short insulin tolerance test.

Conditions
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Coronary Artery Occlusive Dissease

Intervention / Treatment
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* Dietary Supplement: carbohydrate beverage


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: patients who are scheduled to undergo OPCAB Exclusion Criteria: Subjects are ineligible if they have DM(Diabetes Mellitus), Gastroesophageal reflux disease or gastric emptying disorder, inflammatory bowel disease, previous treatment for intra-abdominal cancer, entered surgery more than 5 hours after ingestion of the morning carbohydrate beverage, cognitive dysfunction, disabling mental change disorder, are unable to communicate or speak Korean

Ages Eligible for Study
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Minimum Age: 20 Years
Maximum Age: 79 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: carbohydrate group<br>Randomly selected patients of the carbohydrate group are given 400ml of 12.8 g/100 ml carbohydrate beverage in the evening before their surgery and in the morning of the operation day (3 hours before their scheduled operation). | Dietary Supplement: carbohydrate beverage<br>* 400ml of 12.8 g/100 ml carbohydrate beverage<br>|
| No Intervention: control group<br>Patients in the control group consume no food or drink after midnight before surgery. | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| postoperative insulin resistance |  | within 1 hour after surgery | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| preoperative discomfort | the preoperative discomfort measured by VAS (Visual Analog Scale) | 24 hours | 
| perioperative hemodynamic effect | perioperative hemodynamic effect measured by amount of used vasopressors and minimum mixed venous oxygen saturation | 24 hours | 
| postoperative complications | infection, Myocardiac infarction, Acute renal failure, re-operation, death, etc | 24 hours |