Which conditions warrant glucose control with insulin infusion?

Conditions Warranting Glucose Control with Insulin Infusion

Insulin infusion therapy is indicated for persistent hyperglycemia ≥10 mmol/L (180 mg/dL) in critically ill adults and children, and should be implemented using protocols that minimize the risk of hypoglycemia. 1

Critical Illness Requiring Insulin Infusion

• Critically ill adults with persistent hyperglycemia ≥10 mmol/L (180 mg/dL) should receive insulin infusion therapy with a target blood glucose range of 7.8-11.1 mmol/L (140-200 mg/dL) 1
• Critically ill children with persistent hyperglycemia ≥10 mmol/L (180 mg/dL) should also receive glycemic management, with a strong recommendation against intensive glucose control (4.4-7.7 mmol/L) compared to conventional control (7.8-11.1 mmol/L) 1
• Continuous IV insulin infusion is preferred over intermittent subcutaneous insulin for acute management of hyperglycemia in critically ill adults 1

Specific Clinical Scenarios

Diabetic Emergencies

• Diabetic ketoacidosis (DKA) requires immediate insulin infusion therapy, especially when ketones are present (ketonuria 2+ or ketonaemia ≥1.5 mmol/L) 2, 3
• Hyperosmolar hyperglycemic state (HHS), characterized by glucose ≥600 mg/dL, osmolality ≥320 mOsm/kg, pH >7.3, requires insulin infusion therapy 4, 5
• Severe hyperglycemia (≥300 mg/dL or 16.7 mmol/L) that doesn't respond to subcutaneous insulin requires IV insulin infusion 6, 2

Cardiac Conditions

• Acute myocardial infarction with hyperglycemia (blood glucose >11.0 mmol/L or 200 mg/dL) requires dose-adjusted insulin infusion while avoiding hypoglycemia (<5 mmol/L or 90 mg/dL) 1
• Post-cardiac surgery patients with hyperglycemia benefit from insulin infusion therapy, though targeting conventional glucose control (7.8-11.1 mmol/L) rather than intensive control 1

Implementation of Insulin Infusion

Monitoring Requirements

• Frequent blood glucose monitoring (≤1 hour intervals, continuous or near-continuous) is suggested for critically ill adults on IV insulin during periods of glycemic instability 1
• For pediatric patients on insulin infusion, clinical practice typically involves frequent (≤1 hour) or continuous/near-continuous monitoring systems 1

Protocol Recommendations

• Use protocols with explicit decision support tools for insulin infusion management in both adult and pediatric critically ill patients 1
• Initial insulin infusion rate of 0.1 U/kg/hour is recommended for patients with severe hyperglycemia 2
• Target blood glucose range should be 150-250 mg/dL initially in patients with severe hyperglycemia 2

Transitioning from IV to Subcutaneous Insulin

• Continue IV insulin until blood glucose is <200 mg/dL and metabolic abnormalities are resolved 2
• Calculate subcutaneous insulin requirements based on the total dose of IV insulin administered in the previous 12-24 hours 2
• Maintain the IV insulin infusion for 1-2 hours after initiating subcutaneous insulin to ensure adequate insulin levels 1, 2

Common Pitfalls to Avoid

• Avoid targeting lower blood glucose ranges (4.4-7.7 mmol/L or 80-139 mg/dL) due to increased risk of hypoglycemia 1
• Avoid rapid correction of glucose (not more than 50-75 mg/dL/hour) to prevent neurological complications 2
• Avoid premature termination of IV insulin therapy without appropriate transition to subcutaneous insulin 3
• Avoid relying solely on sliding scale insulin without basal insulin when transitioning from IV insulin 1, 2

Special Considerations

• Monitor serum potassium every 4-6 hours initially, as insulin therapy lowers serum potassium 2
• Include potassium in IV fluids when appropriate to prevent hypokalemia 4, 2
• For patients with type 1 diabetes and severe hyperglycemia, always maintain some insulin to prevent ketosis 6
• Moderate-intensity insulin therapy (avoiding bolus dosing, using liberalized blood glucose targets, and gradual insulin titration) may reduce hospital and ICU length of stay compared to high-intensity insulin therapy 7