How do you manage an insulin drip in a patient with hyperglycemia?

Managing an Insulin Drip in Hyperglycemia

For critically ill patients with hyperglycemia, continuous intravenous insulin infusion at a concentration of 1 unit/mL is the recommended approach, with a target blood glucose range of 140-180 mg/dL for most patients and 110-140 mg/dL for select patients such as those with cardiac surgery or acute neurological events. 1

Initiation Criteria and Preparation

• Begin insulin infusion when blood glucose levels reach ≥180 mg/dL on two consecutive readings 1
• Prepare insulin as a standardized concentration of 1 unit/mL 1
• Prime new tubing with a 20-mL waste volume before starting the infusion to prevent adsorption-related dosing errors 1
• Initial insulin dosing can be calculated at 0.1 U/kg/hour, with adjustments based on the patient's response 2

Protocol Implementation

• Use a standardized insulin infusion protocol or algorithm to guide therapy 1
• Computer-based algorithms are associated with lower rates of hypoglycemia, reduced glycemic variability, and higher percentage of glucose readings within target range 1, 3, 4
• Nurse-managed protocols have demonstrated effectiveness in achieving glycemic targets safely 5, 6

Monitoring Schedule

• Monitor blood glucose every hour initially or more frequently during periods of glycemic instability 1
• Extend monitoring intervals once stable, but maintain frequent monitoring during the first 24-48 hours 1
• Adjust insulin rates according to protocol based on current and previous blood glucose readings 3

Nutritional Considerations

• Evaluate the amount and timing of carbohydrate intake when calculating insulin requirements 5
• Include instructions in protocols to address unplanned discontinuance of any form of carbohydrate infusion 5
• Consistent intake of nutrition simplifies glycemic management during insulin infusion 5
• Avoid overfeeding, which may worsen hyperglycemia 5

Transition to Subcutaneous Insulin

Transition from IV insulin to subcutaneous insulin when:

• Blood glucose levels are stable
• IV insulin infusion rate is low
• Patient is hemodynamically stable
• Patient has a stable nutrition plan
• Normal anion gap (in cases of diabetic ketoacidosis) 5, 1

Calculate the total daily subcutaneous insulin dose using one of these methods:

1. Use 50-60% of the 24-hour IV insulin requirement 1
2. Calculate based on the IV insulin rate during the previous 6-8 hours when glucose was stable 1

Administer 50% as basal insulin (long-acting) and divide the remaining 50% into three equal doses of rapid-acting insulin for meals 1

Special Considerations

Diabetic Ketoacidosis (DKA) and Hyperosmolar Hyperglycemic State (HHS)

• For DKA: Initial insulin bolus of 0.15 U/kg followed by continuous infusion at 0.1 U/kg/hour with a blood glucose target of 250 mg/dL 1
• For HHS: Similar approach with a blood glucose target of 300 mg/dL 1

Safety Considerations

• Insulin is a high-risk medication requiring a systems-based approach to reduce errors 5
• Implement a hypoglycemia management protocol, treating blood glucose <70 mg/dL with 15-20g of fast-acting carbohydrate 1
• Administer glucose immediately for blood glucose <60 mg/dL 1

Common Pitfalls to Avoid

• Failing to adjust insulin rates promptly in response to changing glucose levels
• Not accounting for changes in nutritional intake or steroid administration
• Inadequate monitoring frequency, especially during periods of instability
• Transitioning to subcutaneous insulin too early or without proper overlap
• Relying solely on sliding scale insulin without basal coverage when transitioning to subcutaneous insulin 5, 1

By following these evidence-based recommendations, healthcare providers can effectively manage insulin drips in patients with hyperglycemia while minimizing the risks of both hyper- and hypoglycemia.