What is the recommended protocol for managing hyperglycemia with an insulin drip?

Insulin Infusion Protocol for Hyperglycemia Management

For critically ill patients with hyperglycemia, initiate continuous intravenous insulin infusion when blood glucose reaches ≥150 mg/dL, targeting a range of 140-180 mg/dL using a validated protocol with predefined rate adjustments based on glycemic fluctuations. 1, 2

Critical Care Setting: IV Insulin Infusion

Initiation Criteria and Target Range

• Start IV insulin infusion at blood glucose ≥150 mg/dL, with an absolute upper limit of <180 mg/dL maintained at all times 2
• Target blood glucose of 140-180 mg/dL for most critically ill patients 1, 3
• More stringent targets of 110-140 mg/dL may be appropriate for select patients (cardiac surgery, acute ischemic cardiac or neurologic events) only if achievable without significant hypoglycemia 1, 3

Preparation and Administration

• Prepare insulin infusion at standardized concentration of 1 unit/mL using human regular insulin 2
• Prime new IV tubing with 20-mL waste volume before connecting to patient 2
• Administer via validated written or computerized protocols that allow predefined adjustments based on current and past glucose values and insulin infusion rates 1

Monitoring Requirements

• Check blood glucose every 1-2 hours during active insulin infusion 2
• Never use 4-hourly monitoring intervals—this is associated with hypoglycemia rates >10% 2
• Be aware that point-of-care glucose meters may have significant variability in patients with anemia, hypoxia, or on vasopressors 2

Hypoglycemia Management

• For blood glucose <70 mg/dL: immediately stop or reduce insulin infusion and reassess regimen 2, 3
• For symptomatic or severe hypoglycemia: administer IV dextrose (preferred over glucagon for faster response) 2
• Modern protocols like the updated Yale protocol demonstrate excellent safety with only 0.3% of glucose values <70 mg/dL 2

Nutritional Considerations

• Evaluate amount and timing of carbohydrate intake when calculating insulin requirements 2
• Include specific instructions for unplanned discontinuation of nutrition or dextrose infusions to prevent hypoglycemia 2

Transition from IV to Subcutaneous Insulin

Timing and Dosing

• Administer subcutaneous basal insulin 2 hours before discontinuing IV infusion to prevent rebound hyperglycemia 3
• Calculate total daily subcutaneous dose as 60-80% of the insulin infusion rate during the prior 6-8 hours when stable glycemic goals were achieved 1, 3
• Give half as basal insulin (once or twice daily) and half as rapid-acting insulin (divided before meals) 1

Non-Critical Care Setting: Subcutaneous Insulin

For Patients with Good Oral Intake

• Use basal-bolus regimen with scheduled basal insulin plus prandial and correction doses—this is the preferred treatment 1
• Start with total daily dose of 0.3-0.5 units/kg for insulin-naive patients 1
• Reduce starting dose to 0.15 units/kg in patients at high risk for hypoglycemia (elderly, frail, acute kidney injury) 1
• For patients on home insulin ≥0.6 units/kg/day, reduce total daily dose by 20% to prevent hypoglycemia 1

For Patients with Poor or No Oral Intake

• Use basal insulin or basal-plus-correction regimen (0.1-0.25 units/kg/day basal insulin with correction doses before meals or every 6 hours) 1
• Never use sliding-scale insulin alone—this is strongly discouraged and increases both hypoglycemia and hyperglycemia risk 1, 3

For Type 1 Diabetes Patients

• Always maintain basal insulin even when nothing by mouth 1
• Implement policies to ensure basal insulin is never held during care transitions 1
• Dosing based solely on premeal glucose without accounting for basal needs increases risk of both hypoglycemia and hyperglycemia 1

Critical Safety Considerations

High-Risk Medication Status

• Insulin accounts for approximately one-third of all major drug-related injurious medication errors 1, 2
• Implement standardized protocols, computer provider order entry, and independent double-check of doses 1
• Store insulin away from other medications and avoid abbreviations like "U" for units 1

Common Pitfalls to Avoid

• Do not use sliding-scale insulin as the sole regimen—it results in poorer glycemic control and increased complications 1, 3
• Do not target euglycemia (80-110 mg/dL) in critically ill patients—this substantially increases hypoglycemia risk without mortality benefit 1
• Do not use premixed insulin (70/30) in the hospital—it has unacceptably high rates of iatrogenic hypoglycemia 1

Hypoglycemia Prevention Protocol

• Implement a standardized hospital-wide, nurse-initiated hypoglycemia treatment protocol for blood glucose <70 mg/dL 1, 3
• Document and track all hypoglycemia episodes for quality improvement 1
• Review and modify treatment regimens when blood glucose <70 mg/dL occurs 1