Effect of Preoperative Oral Carbohydrates on the Insulin Resistance of Elderly Patients

Study Overview
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Brief Summary
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Postoperative cognitive dysfunction (POCD) is more common in older patients, and increased insulin resistance is an important factor for POCD. Fasting before surgery is performed to reduce the incidence of pulmonary aspiration after anesthesia. However, prolonged fasting increases insulin resistance. Recently, it is recommended to minimize fasting times and consume carbohydrate drinks before surgery. Therefore, the investigators investigate whether preoperative carbohydrate drinks can reduce insulin resistance in the elderly patients. Fifty patients (age>65 years) scheduled for arthroplasty will be divided into carbohydrate (n=28) and control (n=28) groups. Randomly selected patients of the carbohydrate group are given 400ml of 12.8 g/100 ml carbohydrate beverage 2-3 hours before their scheduled operation. In contrast, patients in the control group are fasted from water 2 h before surgery according to standard protocol.

Official Title
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Effect of Preoperative Oral Carbohydrates on the Insulin Resistance of Elderly Patients

Conditions
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Old Age

Intervention / Treatment
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* Dietary Supplement: carbohydrate group - carbohydrate (400ml)


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients undergoing arthroplasty age>65 years Exclusion Criteria: The subject is a foreigner or illiterate Patients with gastroesophageal reflux disease, gastric emptying disorders, inflammatory bowel disease, or previous treatment for intra-abdominal cancer Patients with chronic renal disease or severe cardiovascular disease HbA1c >69 mmol/mol or BMI >30 kg/m2 A duration of ≥5 h between consumption of CHO and initiation of surgery.

Ages Eligible for Study
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Minimum Age: 65 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: Prevention
Allocation: Randomized
Intervention Model: Parallel Assignment
Interventional Model Description: Randomly selected patients of the carbohydrate group are given oral carbohydrate (400ml) 2-3 hours before surgery. In contrast, patients in the control group are fasted water 2 hours before surgery.
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Carbohydrate group<br> | Dietary Supplement: carbohydrate group - carbohydrate (400ml)<br>* Randomly selected patients of the carbohydrate group are given oral carbohydrate (400ml) 2-3 hours before surgery. In contrast, patients in the control group are fasted water 2 hours before surgery according to the standard protocol.<br>|
| No Intervention: Control group<br> | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Insulin resistance | Insulin resistance index = glucose x insulin/22.5 | Before anesthesia | 
| Insulin resistance | Insulin resistance index = glucose x insulin/22.5 | 1 hour after surgery | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| glycemic variability | Coefficient of glucose variability =SD/mean x 100 (%) | Before anesthesia | 
| glycemic variability | Coefficient of glucose variability =SD/mean x 100 (%) | 5 minutes after anesthesia | 
| glycemic variability | Coefficient of glucose variability =SD/mean x 100 (%) | 1 hour after surgery | 
| glycemic variability | Coefficient of glucose variability =SD/mean x 100 (%) | 10 minutes after admission of recovery room |