Glucose-Insulin-Potassium (GIK) Regimen for Diabetic Inpatients
For diabetic inpatients, continuous intravenous insulin infusion is the preferred method for achieving glycemic targets in the critical care setting, while a basal-bolus insulin regimen is recommended for non-critically ill patients rather than a GIK regimen. 1
Critical Care Setting Management
Preferred Approach
- Continuous intravenous insulin infusion is the most effective method for glycemic control in critically ill patients 1
- Target blood glucose range: 140-180 mg/dL (7.8-10.0 mmol/L) 1
- Lower targets (80-110 mg/dL) have been associated with increased mortality and 10-15 fold higher rates of hypoglycemia 1
Implementation of Insulin Infusion
- Administer based on validated written or computerized protocols 1
- Allow for predefined adjustments in infusion rate based on:
- Glycemic fluctuations
- Insulin dose requirements
- Frequent monitoring required:
- Blood glucose testing every 30 minutes to 2 hours 1
Transitioning from IV to Subcutaneous Insulin
When transitioning from IV insulin to subcutaneous regimen, consider:
- Patient stability (stable glucose measurements for 4-6 hours)
- Resolution of acidosis if diabetic ketoacidosis was present
- Hemodynamic stability (not on vasopressors)
- Stable nutrition plan 1
Calculate subcutaneous insulin requirements based on IV infusion rates:
- Use average insulin infusion rate over previous 12 hours
- Example: Average of 1.5 units/hour = approximately 36 units/24 hours total daily dose 1
Non-Critical Care Setting Management
Recommended Regimen
- For patients with good nutritional intake: Basal, prandial, and correction insulin components 1
- For patients with poor oral intake or NPO: Basal insulin plus correction insulin 1
Important Considerations
- Sliding scale insulin alone is strongly discouraged 1
- For patients who are eating:
- Perform glucose monitoring before meals
- Align insulin injections with meals
- For patients not eating:
- Monitor glucose every 4-6 hours
- Consider administering rapid/short-acting insulin every 4-6 hours 1
Glucose-Insulin-Potassium (GIK) Specific Information
While current guidelines don't recommend GIK as standard care for all diabetic inpatients, some research has shown potential benefits in specific scenarios:
- Surgical settings: GIK has been used successfully in diabetic patients undergoing surgery, particularly cardiac surgery 2, 3
- Benefits observed in some studies include:
GIK Protocol Components (when used)
- Typical composition: 10 units of soluble insulin per 500 ml of 10% glucose (0.32 units/g glucose) with potassium supplementation 2
- Requires careful monitoring of:
- Blood glucose levels
- Potassium levels (to prevent hypokalemia)
- Sodium levels (may decrease during infusion) 2
Monitoring Recommendations
- Bedside glucose monitoring:
- For eating patients: Before meals
- For non-eating patients: Every 4-6 hours
- For IV insulin: Every 30 minutes to 2 hours 1
- Potassium monitoring:
- Particularly important during treatment of hyperglycemic crises
- Hypokalaemia is common (about 50%) and severe hypokalaemia (<2.5 mEq/L) is associated with increased mortality 1
Common Pitfalls to Avoid
- Using sliding scale insulin alone (reactive approach) instead of scheduled insulin regimens (proactive approach) 1
- Failing to transition appropriately from IV to subcutaneous insulin
- Inadequate monitoring of potassium levels during insulin therapy
- Targeting overly strict glycemic control (80-110 mg/dL), which increases hypoglycemia risk and mortality 1
- Insufficient monitoring frequency when using IV insulin
While some historical and specialized surgical settings have used GIK regimens with success, current guidelines from major diabetes organizations recommend continuous IV insulin for critical care and basal-bolus regimens for non-critical care settings as the standard of care for inpatient diabetes management.