What is the recommended starting insulin regimen for inpatient diabetes management on admission?

Starting Insulin Regimen for Inpatient Diabetes Management

Recommended Approach Based on Glycemic Severity

For non-critically ill hospitalized patients with diabetes, use a basal-bolus insulin regimen starting at 0.3 units/kg/day total daily dose (TDD), with half given as basal insulin once daily and half as rapid-acting insulin before meals, rather than sliding scale insulin alone. 1

Stratified Insulin Initiation by Hyperglycemia Severity

The most recent guidelines recommend tailoring your starting regimen based on admission blood glucose levels 1:

Mild Hyperglycemia (BG <200 mg/dL)

• Start with low-dose basal insulin (0.1 units/kg/day) or consider DPP-4 inhibitor 1
• Add correction doses with rapid-acting insulin before meals or every 6 hours 1
• This simplified approach is appropriate for insulin-naive patients or those with low home insulin requirements 1

Moderate Hyperglycemia (BG 201-300 mg/dL)

• Start basal insulin at 0.2-0.3 units/kg/day 1
• Add correction doses with rapid-acting insulin before meals 1
• May combine with oral agents if no contraindications exist 1

Severe Hyperglycemia (BG >300 mg/dL)

• Initiate full basal-bolus regimen at 0.3 units/kg/day TDD 1
• Split dose: 50% as basal insulin once daily, 50% as prandial insulin divided before meals 1
• If patient was on home insulin >0.6 units/kg/day, reduce their home TDD by 20% 1

Special Considerations for Reduced Oral Intake

For patients with poor or no oral intake (NPO), use basal insulin plus correction insulin only—do not give prandial insulin. 1, 2

• Reduce starting dose to 0.1-0.15 units/kg/day given mainly as basal insulin 1
• Add rapid-acting insulin as correctional coverage for glucose >180 mg/dL 1
• This prevents hypoglycemia when nutritional intake is unpredictable 1

Critical Pitfalls to Avoid

Never use sliding scale insulin (SSI) alone as the sole regimen—this is strongly discouraged by all major guidelines. 1, 3, 2

• SSI alone results in poorer glycemic control and increased hospital complications compared to basal-bolus regimens 1, 3
• Multiple randomized trials demonstrate basal-bolus regimens achieve better glycemic control with lower rates of perioperative complications 1

Avoid premixed insulin formulations in the hospital setting. 1, 2

• Premixed insulin causes a threefold higher rate of hypoglycemia compared to basal-bolus regimens with insulin analogs 1
• The fixed ratios cannot be adjusted for variable oral intake 1

Insulin Analog Selection

Use long-acting basal insulin analogs (glargine, detemir) rather than NPH insulin when possible. 1

• NPH has a peak action 8-12 hours after injection, creating hypoglycemia risk in patients with poor oral intake 1
• Insulin analogs provide more physiologic action with lower hypoglycemia risk 4
• For prandial coverage, use rapid-acting analogs (lispro, aspart, glulisine) 1

Dose Adjustments for High-Risk Patients

In frail, elderly patients or those with acute kidney injury, reduce the starting dose to 0.15 units/kg/day to minimize hypoglycemia risk. 1

• These patients have increased vulnerability to severe hypoglycemia 1
• Start conservatively and titrate upward based on glucose monitoring 1

Type 1 Diabetes Exception

Patients with type 1 diabetes require basal insulin at all times, even when NPO—never hold basal insulin in this population. 2

• Type 1 diabetes patients must receive concomitant short-acting insulin with basal insulin 5
• Recommended starting dose is approximately one-third of total daily requirements as basal insulin 5

Monitoring and Titration

Target premeal blood glucose <140 mg/dL and random blood glucose <180 mg/dL for most non-critically ill patients. 1

• More stringent targets may be appropriate in stable patients with previous tight control 1
• Less stringent targets are appropriate for patients with severe comorbidities 1
• Increase frequency of blood glucose monitoring during any insulin regimen changes 5