What dose of regular insulin is appropriate for a patient with a blood glucose level of hyperglycemia?

Correction Insulin Dosing for Blood Glucose of 307 mg/dL

For a blood glucose of 307 mg/dL in a hospitalized or acute care setting, administer 10-15 units of regular insulin subcutaneously, based on standard correction scales that recommend 5 units for every 50 mg/dL above 150 mg/dL. 1

Immediate Dosing Algorithm

For non-DKA hyperglycemia with blood glucose of 307 mg/dL:

• Calculate correction dose: Using the standard hospital protocol, give 5 units of regular insulin for every 50 mg/dL increment above 150 mg/dL 1

  • 307 mg/dL is approximately 150 mg/dL above target (150 mg/dL baseline)
  • This translates to 10-15 units of regular insulin subcutaneously 1

• Alternative calculation using insulin sensitivity factor: If the patient's total daily insulin dose (TDD) is known, use the formula ISF = 1500 ÷ TDD to determine how much one unit will lower blood glucose 2

  • For example, if TDD is 50 units, then ISF = 30 mg/dL per unit
  • To lower from 307 to target of ~130 mg/dL (difference of 177 mg/dL), give approximately 6 units
  • However, this approach requires knowing the patient's established insulin regimen 2

Critical Considerations Before Administering

Rule out diabetic ketoacidosis (DKA) first:

• If DKA is present (pH <7.3, bicarbonate <18 mEq/L, ketones present), do not use subcutaneous correction insulin alone 1
• DKA requires continuous intravenous insulin infusion at 0.1 unit/kg/hour after an initial bolus of 0.15 units/kg 1

Assess the patient's insulin status:

• For insulin-naive patients with blood glucose >300 mg/dL: A single correction dose is insufficient—these patients require initiation of a basal-bolus regimen with total daily dose of 0.3-0.5 units/kg 1, 3
• For patients already on home insulin ≥0.6 units/kg/day: Reduce their total daily dose by 20% during hospitalization before adding correction insulin to prevent hypoglycemia 1, 3

Timing and Monitoring

• Regular insulin should be administered subcutaneously every 4-6 hours as needed for correction of hyperglycemia 1
• Rapid-acting insulin analogs can be given every 4 hours as an alternative, with faster onset but similar correction effect 1
• Recheck blood glucose in 4-6 hours after regular insulin administration to assess response 1

Common Pitfalls to Avoid

Never rely on correction insulin alone:

• Sliding scale insulin monotherapy is strongly discouraged and associated with poor glycemic control 1, 3
• A blood glucose of 307 mg/dL indicates the need for a scheduled basal-bolus regimen, not just correction doses 1, 3

Avoid insulin stacking:

• Do not administer another correction dose within 4-6 hours of the previous regular insulin dose, as the prior dose may still be active 2, 1
• Regular insulin has a duration of action of 6-8 hours after subcutaneous injection 1

Reduce doses in high-risk patients:

• For patients >65 years old, with renal failure, or poor oral intake, use lower correction doses (maximum 10-15 units rather than 20 units for glucose of 300 mg/dL) 1, 3

Transition to Scheduled Insulin Therapy

After giving correction insulin, establish a basal-bolus regimen:

• Calculate total daily insulin needs as 0.3-0.5 units/kg for patients with severe hyperglycemia 1, 3
• Give 50% as basal insulin (once daily long-acting) and 50% as prandial insulin (divided among three meals) 1, 3
• Continue correction insulin every 4-6 hours as needed in addition to the scheduled regimen 1, 3