What is the Humalog (insulin lispro) IV protocol for critically ill patients in the Intensive Care Unit (ICU)?

Humalog IV Protocol for ICU Patients

For critically ill patients in the ICU, intravenous Humalog (insulin lispro) should be administered using a standardized protocol with a target blood glucose range of 140-180 mg/dL, initiated when blood glucose exceeds 180 mg/dL on two consecutive measurements. 1

Initiation Criteria

• Begin IV insulin infusion when two consecutive blood glucose readings are >180 mg/dL 1, 2
• Target blood glucose range should be 140-180 mg/dL for most ICU patients 1, 2
• More stringent goals (110-140 mg/dL) may be appropriate for select patients such as cardiac surgery patients or those with acute ischemic cardiac/neurological events, but only if achievable without significant hypoglycemia 1

Administration Protocol

• Use a validated written or computerized protocol that allows for predefined adjustments in insulin infusion rate 1, 2
• Computer-based algorithms are preferred as they have demonstrated lower rates of hypoglycemia, reduced glycemic variability, and higher percentage of glucose readings within target range 1, 2
• Administer insulin lispro using an electronic pump for greater precision 2
• Initial dosing for intravenous Humalog is typically 0.5 units/hour, adjusted based on blood glucose levels 3

Monitoring Requirements

• Monitor blood glucose every 1-2 hours until glucose values and insulin infusion rates are stable 2
• Once stable, monitoring can be reduced to every 4 hours 2
• Use arterial blood instead of capillary blood for glucose testing if patients have arterial catheters 2
• Capillary blood glucose measurements should be interpreted with caution in critically ill patients 2

Protocol Adjustments

• Insulin infusion protocols should include instructions to address unplanned discontinuance of any form of carbohydrate infusion 1
• Evaluate the amount and timing of carbohydrate intake when calculating insulin requirements 1
• Adjust insulin rates according to protocol parameters based on current blood glucose level, rate of change, and previous insulin requirements 1, 2

Pharmacokinetics of IV Humalog

• When administered intravenously, Humalog's pharmacologic effect begins at approximately 10-15 minutes 3
• The effect terminates at a median time of approximately 4 hours (range: 2-6 hours) after administration 3
• IV Humalog has been shown to effectively lower blood glucose to target range in critically ill patients 3

Transition from IV to Subcutaneous Insulin

• When the patient is stable and approaching ICU discharge, calculate the total daily dose of IV insulin administered in the previous 24 hours 2
• Administer half of this dose as long-acting basal insulin once daily, and the other half divided into three doses of rapid-acting insulin before meals 2
• Maintain IV infusion for 1-2 hours after the first dose of subcutaneous insulin to avoid hyperglycemic rebound 2

Safety Considerations

• Implement strategies to reduce errors, such as standardized protocols and minimizing available insulin products 1, 2
• Perform independent verification of doses, frequent glucose monitoring, and prominent labeling of products 1, 2
• Avoid abbreviations like "U" for units, and store insulin separately from other medications 1, 2
• Be aware that hypoglycemia (glucose <60 mg/dL) is a serious risk that must be avoided 1, 4

Special Considerations for Elderly Patients

• Elderly patients are at increased risk of hypoglycemia due to impaired counterregulatory responses 1
• Follow general clinical guidelines but with greater emphasis on preventing hypoglycemia in older adults 1
• The same target glucose range (140-180 mg/dL) applies, but with heightened vigilance for hypoglycemia 1