Insulin Infusion Support in Day Care for Severe Hyperglycemia
Indications for Insulin Infusion
Continuous intravenous insulin infusion is recommended for severe hyperglycemia in day care settings when patients present with diabetic ketoacidosis (DKA), hyperglycemic hyperosmolar state (HHS), or critically ill status requiring intensive glucose monitoring. 1
Specific Clinical Scenarios Requiring IV Insulin:
- DKA or HHS management: Correction of hyperglycemia, hyperketonemia, and acid-base disorders 1
- Critically ill patients: When blood glucose exceeds 180 mg/dL and requires tight glycemic control 1
- Severe hyperglycemia: Blood glucose ≥300-350 mg/dL with symptomatic or catabolic features 1
- Perioperative management: Patients undergoing procedures requiring NPO status with unstable glucose control 1
When IV Insulin is NOT Appropriate:
- Mild, uncomplicated DKA: Can be managed with subcutaneous rapid-acting insulin every 1-2 hours 1
- Noncritically ill patients with moderate hyperglycemia: Subcutaneous basal-bolus regimens are preferred 1, 2
Dosage and Administration Protocols
Initial IV Insulin Infusion Setup:
Start with regular insulin (Humulin R U-100) at concentrations of 0.1 to 1 unit/mL in 0.9% sodium chloride using polyvinyl chloride infusion bags. 3
DKA/HHS Protocol:
- Fixed-rate infusion: 0.1 units/kg/hour as continuous IV infusion 1
- Alternative variable-rate protocol: Nurse-driven protocol with adjustments based on hourly glucose values 1
- Starting threshold: Initiate when glucose >180 mg/dL in critically ill patients 1
Critical Care Glycemic Targets:
- Target range: Maintain glucose between 140-180 mg/dL once infusion is started 1, 2
- Starting threshold: No higher than 180 mg/dL 1
- Avoid: Targets <110 mg/dL due to increased hypoglycemia risk 1
Practical Infusion Rate Adjustments:
Use validated written or computerized protocols that allow predefined adjustments based on:
- Current glucose level 1
- Magnitude of glucose change in the previous hour 4
- Immediate past insulin infusion rates 1
Example Titration Algorithm:
- If glucose ≥180 mg/dL: Start at 0.5 units/hour, adjust to maintain 100-160 mg/dL 3
- Hourly monitoring: Check blood glucose every hour during infusion 1, 4
- Rate adjustments: Modify infusion rate based on glucose trends, not single readings 4
Monitoring Requirements
Essential Monitoring Parameters:
- Glucose monitoring: Hourly point-of-care glucose testing during active infusion 1, 4
- Potassium levels: Close monitoring to avoid hypokalemia 3
- Acid-base status: For DKA/HHS management 1
- Hypoglycemia surveillance: Immediate treatment protocol for glucose <70 mg/dL 1
Infusion Stability:
- Prepared infusion bags: Stable for 48 hours refrigerated (2-8°C), then additional 48 hours at room temperature 3
Transition to Subcutaneous Insulin
When to Transition:
- DKA resolution: When hyperglycemia, hyperketonemia, and acid-base disorder are corrected 1
- Clinical stability: Patient able to tolerate oral intake 1
- Glucose stabilization: Consistent glucose readings in target range 2
Conversion Formula:
Total subcutaneous dose = 1/2 of IV insulin infused over 24 hours 5
- Give 50% as basal insulin once in the evening 5
- Divide remaining 50% by 3 for rapid-acting insulin before each meal 5
Critical Pitfalls to Avoid
- Never use IV insulin without validated protocols: Increases risk of hypoglycemia and dosing errors 1
- Never target glucose <110 mg/dL: Associated with increased hypoglycemia without mortality benefit 1
- Never abruptly discontinue IV insulin: Overlap with subcutaneous insulin by 1-2 hours to prevent rebound hyperglycemia 1
- Never use sliding scale insulin as monotherapy: Treats hyperglycemia reactively rather than preventing it 6, 7
- Never delay hypoglycemia treatment: Treat any glucose <70 mg/dL immediately with 15 grams fast-acting carbohydrate 1
Day Care-Specific Considerations
For day care settings, ensure: