What is the initial insulin infusion rate in units per hour for an adult patient weighing 61.2 kg with Diabetic Ketoacidosis (DKA)?

Initial Insulin Infusion Rate for Adult Patient with DKA

For an adult patient weighing 61.2 kg with diabetic ketoacidosis (DKA), the initial insulin infusion rate should be 0.1 units/kg/hour, which equals 6.12 units/hour. 1, 2

Initial Management Protocol

• For adult patients with DKA, start with an intravenous infusion of regular insulin at 0.1 units/kg/hour (approximately 5-7 units/hour in adults), which equals 6.12 units/hour for a 61.2 kg patient 1
• Some protocols recommend an initial bolus of 0.15 units/kg IV (approximately 9.2 units for this patient) before starting the continuous infusion, but recent evidence suggests this may increase adverse effects without significant clinical benefit 1, 3
• Avoid insulin bolus in pediatric patients with DKA 1

Monitoring and Adjustments

• Monitor blood glucose every 1-2 hours until glucose values and infusion rates are stable, then every 4 hours 1
• If blood glucose does not decrease by at least 50 mg/dL in the first hour:
  • Verify hydration status
  • If hydration is adequate, double the insulin infusion rate every hour until achieving a steady glucose decrease of 50-75 mg/dL/hour 1, 2

Glucose Management During Treatment

• When blood glucose falls below 250-300 mg/dL, add dextrose (D5W or D10W) to the IV fluids while continuing insulin infusion 1, 2
• Target glucose between 150-200 mg/dL until DKA resolution criteria are met 2
• Do not interrupt insulin infusion when glucose levels fall - this is a common cause of persistent ketoacidosis 2

Criteria for DKA Resolution

• Glucose <200 mg/dL 2
• Serum bicarbonate ≥18 mEq/L 2
• Venous pH >7.3 2
• Anion gap ≤12 mEq/L 2

Transition to Subcutaneous Insulin

• When DKA is resolved and the patient can eat, initiate subcutaneous insulin with a combination of short/rapid-acting and intermediate/long-acting insulin 1, 2
• Continue IV insulin infusion for 1-2 hours after starting subcutaneous insulin to ensure adequate plasma insulin levels 2

Important Considerations

• Ketonemia typically takes longer to clear than hyperglycemia, necessitating continued insulin therapy even after glucose normalizes 2
• Direct measurement of β-hydroxybutyrate in blood is the preferred method for monitoring DKA resolution 2
• Monitor electrolytes, especially potassium, every 2-4 hours during treatment 1, 2

Alternative Approaches

• Recent research suggests subcutaneous rapid-acting insulin analogs may be a safe alternative to IV insulin for mild to moderate uncomplicated DKA, but this approach is not standard for initial management 4, 5
• Early administration of long-acting insulin (glargine) in combination with IV insulin may lead to faster DKA resolution and shorter hospital stays 6