How is correction insulin administered to patients with hyperglycemia?

How to Administer Correction Insulin for Hyperglycemia

Correction insulin should be administered as rapid-acting insulin (aspart, lispro, or glulisine) subcutaneously before meals or every 4-6 hours if the patient is not eating, but sliding scale insulin alone is strongly discouraged and should only be used in patients without diabetes who have mild stress hyperglycemia—never as monotherapy in patients with established diabetes. 1

Key Principle: Correction Insulin Must Be Part of a Scheduled Regimen

• Sliding scale insulin (SSI) alone is associated with clinically significant hyperglycemia and provides no benefit—in fact, when used without basal insulin, it increases the risk of hyperglycemic episodes 3-fold compared to no treatment at all. 1, 2

• The American Diabetes Association explicitly states that use of only sliding scale insulin in the inpatient hospital setting is strongly discouraged. 1

• Correction insulin should be administered as part of a basal-bolus regimen, not as standalone reactive treatment. 1

Practical Examples of Correction Insulin Administration

Example 1: Basal-Bolus Regimen with Correction Doses

For insulin-naive patients or those on low-dose insulin:

• Calculate total daily dose (TDD) at 0.3-0.5 units/kg (use lower doses for elderly patients >65 years, those with renal failure, or poor oral intake). 1

• Allocate 50% as basal insulin (given once or twice daily) and 50% as rapid-acting insulin (divided before three meals). 1

• Add correction doses of rapid-acting insulin before each meal using a correction scale. 1

Specific correction scale example:

• Blood glucose 140-180 mg/dL: add 2 units
• Blood glucose 181-220 mg/dL: add 4 units
• Blood glucose 221-260 mg/dL: add 6 units
• Blood glucose 261-300 mg/dL: add 8 units
• Blood glucose >300 mg/dL: add 10 units and notify physician 3

Example 2: Basal-Plus Approach (For Mild Hyperglycemia)

For patients with blood glucose <200 mg/dL or decreased oral intake:

• Give basal insulin 0.1-0.25 units/kg per day as a single dose. 1

• Administer correction doses of rapid-acting insulin before meals or every 6 hours (if nil by mouth). 1

• Use regular human insulin every 6 hours or rapid-acting insulin every 4 hours for correction. 1

Example 3: Transitioning from IV Insulin to Subcutaneous

When moving a patient from continuous insulin infusion:

• Calculate the average insulin infusion rate over the preceding 12 hours. 1

• Multiply by 24 to estimate total daily dose (e.g., 1.5 units/hour × 24 = 36 units/day). 1

• Give 50% as basal insulin and 50% divided as prandial/correction doses. 1

Example 4: Patients on Enteral Nutrition

For continuous tube feeding:

• Calculate 1 unit of insulin per 10-15 grams of carbohydrate in the formula. 1

• Use NPH insulin every 8-12 hours to cover nutritional needs. 1

• Add correction insulin subcutaneously every 6 hours using regular insulin or every 4 hours using rapid-acting insulin. 1

For bolus tube feeding:

• Give 1 unit of rapid-acting insulin per 10-15 grams carbohydrate before each feeding. 1

• Add correction insulin as needed before each feeding. 1

Example 5: Patients on Glucocorticoids

For once-daily morning steroids (e.g., prednisone):

• Use NPH insulin or prandial insulin to cover daytime hyperglycemia, as glucose typically normalizes overnight. 1

• Increase prandial and correction insulin doses substantially—sometimes in extraordinary amounts—as steroids progress. 1

• For long-acting glucocorticoids (dexamethasone) or continuous use, add long-acting basal insulin to control fasting glucose. 1

Timing and Frequency of Correction Insulin

• For eating patients: Administer correction insulin before meals (typically 3 times daily). 1

• For NPO patients: Administer correction insulin every 4-6 hours. 1

• Rapid-acting insulins (aspart, lispro, glulisine): Give every 4 hours for correction. 1

• Regular human insulin: Give every 6 hours for correction. 1

Insulin Selection for Correction Doses

Preferred agents are rapid-acting insulin analogs:

• Insulin aspart, lispro, or glulisine are recommended because their time-action profiles more closely correspond to physiological needs and have lower hypoglycemia risk than regular human insulin. 4

• These insulins are indistinguishable from each other in terms of blood levels and metabolic effects. 5

• Ultra-rapid-acting formulations (faster aspart, lispro-aabc) provide additional flexibility with quicker onset but similar A1C lowering and hypoglycemia risk. 6

Critical Pitfalls to Avoid

Never Use Sliding Scale Insulin Alone

• SSI alone is ineffective—studies show it provides no benefit and is associated with suboptimal glycemic control in 51-68% of patients. 7, 2

• SSI should never be used in patients with type 1 diabetes as it excludes basal insulin, risking diabetic ketoacidosis. 1

Avoid Insulin Stacking

• Do not administer correction doses more frequently than every 4 hours (for rapid-acting) or 6 hours (for regular insulin) to prevent cumulative hypoglycemia. 1

• Be especially vigilant overnight when hypoglycemia may go undetected. 3

Adjust for High-Risk Patients

• Reduce total daily dose by 20% for patients on ≥0.6 units/kg/day at home to prevent hypoglycemia with poor oral intake. 1

• Use lower starting doses (0.1-0.25 units/kg) for elderly patients, those with renal failure, or poor oral intake. 1

Monitor and Adjust Appropriately

• Hypoglycemia risk with basal-bolus is 4-6 times higher than with SSI alone, requiring vigilant glucose monitoring. 1

• 73-75% of patients never have their insulin adjusted despite persistent hyperglycemia—daily dose adjustments are essential. 7

• After hypoglycemia occurs, 84% of patients will have another episode during the same admission if the regimen is not modified. 1

Special Populations

Patients without diabetes with mild stress hyperglycemia:

• SSI alone may be appropriate in this specific population only. 1

Patients with good metabolic control on oral agents at home:

• Consider SSI alone initially, but add basal insulin if unable to maintain glucose <180 mg/dL. 1

Patients receiving parenteral nutrition:

• Add regular insulin to the solution if >20 units of correction insulin required in past 24 hours, starting with 1 unit per 10 grams dextrose. 1