Emergency Regular Insulin Dosing Based on Capillary Blood Glucose
For emergency correction of hyperglycemia in hospitalized non-critically ill patients, use a standardized supplemental insulin scale based on the current CBG level and the patient's insulin sensitivity, administering regular insulin every 6 hours or rapid-acting insulin every 4-6 hours. 1
Standardized Correction Dose Scale
The Endocrine Society provides a validated correction insulin scale that should be applied based on three patient categories 1:
Insulin-Sensitive Column (Start Here For):
- Patients who are NPO (not eating)
- Elderly patients (≥70 years)
- Patients with impaired renal function (GFR <60 mL/min)
Usual Column (Start Here For):
- Most patients able to eat
- Standard insulin requirements
Insulin-Resistant Column (Start Here For):
- Patients receiving corticosteroids
- Patients previously treated with >80 units/day of insulin
Correction Dose Table
| CBG (mg/dL) | Insulin-Sensitive | Usual | Insulin-Resistant |
|---|---|---|---|
| 141-180 | 2 units | 4 units | 6 units |
| 181-220 | 4 units | 6 units | 8 units |
| 221-260 | 6 units | 8 units | 10 units |
| 261-300 | 8 units | 10 units | 12 units |
| 301-350 | 10 units | 12 units | 14 units |
| 351-400 | 12 units | 14 units | 16 units |
| ≥400 | 14 units | 16 units | 18 units |
Administration Timing
Regular insulin: Administer every 6 hours (at 6-12-6-12 schedule) 1
Rapid-acting insulin analog: Administer every 4-6 hours 1
For eating patients: Give correction dose before each meal and at bedtime, using the "Usual" column. Give half the supplemental insulin dose at bedtime. 1
Critical Implementation Points
Common Pitfalls to Avoid:
Never use sliding-scale insulin (SSI) as monotherapy - This outdated approach increases the risk of hyperglycemia 3-fold and results in undesirable glycemic control 1. Correction insulin should be part of a scheduled basal-bolus regimen, not standalone therapy.
Adjust for renal function - Patients with kidney failure have decreased insulin clearance and require lower starting doses in the insulin-sensitive column 2.
Account for insulin action time - Regular insulin has 4-6 hours of action. Do not "stack" doses by giving correction insulin more frequently than every 6 hours with regular insulin 3.
Bedtime dosing reduction - Always give only half the correction dose at bedtime to prevent nocturnal hypoglycemia 1.
Alternative Calculation Method (Insulin Sensitivity Factor)
For patients on established insulin regimens, you can calculate correction doses using the insulin sensitivity factor (ISF):
For regular insulin: ISF = 1500 ÷ Total Daily Dose (TDD) of insulin 3
For rapid-acting insulin: ISF = 1800 ÷ TDD of insulin 3
This tells you how many mg/dL one unit of insulin will lower the blood glucose. For example, if a patient uses 50 units/day total: 1800 ÷ 50 = 36 mg/dL reduction per unit.
Correction dose = (Current CBG - Target CBG) ÷ ISF
However, this method requires knowledge of the patient's home insulin regimen and is more complex than using the standardized scale above.
When to Escalate
If CBG remains persistently >240 mg/dL despite correction doses, the patient requires initiation or adjustment of scheduled basal-bolus insulin therapy, not just increased correction doses 1. In one study, 14% of patients on SSI alone required rescue with basal-bolus insulin due to persistent hyperglycemia 1.
For critically ill patients or those with CBG consistently >300 mg/dL, consider continuous intravenous insulin infusion rather than subcutaneous correction doses 4, 2.