Correction Insulin Dosing for Severe Hyperglycemia on the Hospital Floor
For a blood glucose of 420 mg/dL in a hospitalized patient on the floor, administer 6-8 units of rapid-acting insulin as correction dose, then immediately reassess and implement a scheduled basal-bolus insulin regimen rather than relying on correction insulin alone. 1
Immediate Correction Dose Calculation
The correction insulin dose depends on the patient's insulin sensitivity factor (ISF), typically calculated as 1500 ÷ total daily insulin dose (TDD). For insulin-naive patients, a reasonable starting assumption is an ISF of approximately 30-50 mg/dL per unit of insulin. 2
Standard Correction Scale for Hospitalized Patients
For blood glucose 261-300 mg/dL: 6 units of rapid-acting insulin 3
For blood glucose >300 mg/dL: 8 units of rapid-acting insulin and notify physician 3
With a blood glucose of 420 mg/dL, this patient requires 8 units of rapid-acting insulin immediately, followed by physician notification for regimen adjustment. 3
Critical Pitfall: Sliding Scale Insulin Alone is Inadequate
Relying solely on correction (sliding scale) insulin for persistent hyperglycemia is ineffective and dangerous. Studies demonstrate that 14% of patients treated with sliding scale insulin alone remained with blood glucose >240 mg/dL despite increasing doses. 1 The correction dose addresses the acute hyperglycemia, but a scheduled basal-bolus regimen must be implemented to prevent recurrence. 1
Implementing a Scheduled Basal-Bolus Regimen
Initial Total Daily Dose Calculation
For hospitalized patients with moderate-to-severe hyperglycemia (blood glucose 201-400 mg/dL), start with 0.4-0.5 units/kg/day as total daily insulin dose. 1, 4
For a 70 kg patient: 0.5 units/kg/day × 70 kg = 35 units total daily dose 1
Distribution of Insulin Doses
Give 50% as basal insulin (insulin glargine) once daily: 17-18 units 1, 4
Give 50% as prandial insulin (rapid-acting) divided before three meals: approximately 6 units before each meal 1, 4
This basal-bolus approach achieves blood glucose <140 mg/dL in 66% of patients compared to only 38% with sliding scale insulin alone, with an overall blood glucose difference of 27 mg/dL. 1
Monitoring and Titration Requirements
Check blood glucose every 6 hours minimum, or before meals if eating. 3 Target blood glucose is 140-180 mg/dL in hospitalized patients. 3
Adjust basal insulin by 2-4 units every 3 days based on fasting glucose patterns:
- If fasting glucose ≥180 mg/dL: increase by 4 units 5
- If fasting glucose 140-179 mg/dL: increase by 2 units 5
- If fasting glucose <80 mg/dL on more than 2 occasions: decrease by 2 units 2
Special Considerations for High-Risk Patients
For elderly patients (>65 years), those with renal failure, or poor oral intake, use lower doses of 0.1-0.25 units/kg/day to prevent hypoglycemia. 2 In these patients, the correction dose should also be reduced proportionally.
If the patient is on high-dose glucocorticoids (such as dexamethasone), insulin requirements increase by 0.3-0.4 units/kg/day, with 75% given as prandial insulin and 25% as basal insulin. 3 The correction scale should be more aggressive, and blood glucose should be monitored more frequently as peak hyperglycemia occurs 6-12 hours post-steroid dose. 3
Why Basal-Bolus is Superior to Sliding Scale Alone
Scheduled basal-bolus insulin regimens reduce hypoglycemia by 50% (from 4% to 2% of measurements) while achieving 75% of blood glucose measurements in target range versus only 61% with sliding scale insulin. 4 The basal component addresses fasting and between-meal glucose, while prandial insulin controls postprandial excursions—correction insulin alone cannot accomplish both. 5, 1
Hyperglycemia in hospitalized patients increases infection risk through impaired polymorphonuclear leukocyte mobilization, chemotaxis, and phagocytic activity. 6 Maintaining tight glycemic control with intensive insulin therapy (target 80-110 mg/dL in ICU, 140-180 mg/dL on floors) decreases infection-related complications and mortality. 6