What type of insulin is recommended for a patient with hyperglycemia?

Insulin Selection for Hyperglycemia Management

For patients with hyperglycemia, basal insulin (such as insulin glargine, detemir, or degludec) should be initiated first, with the addition of prandial insulin if glycemic targets are not achieved with basal insulin alone. 1

Initial Insulin Selection Algorithm

For Non-Critical Care Patients:

• Severe hyperglycemia (blood glucose ≥300 mg/dL, A1C >10%) with symptoms (polyuria, polydipsia, weight loss):

  • Begin with basal insulin (insulin glargine, detemir, or degludec) while initiating metformin 1
  • Starting dose: 10 units or 0.1-0.2 units/kg once daily 2
  • If marked hyperglycemia with ketosis/ketoacidosis: Start with subcutaneous or IV insulin to rapidly correct metabolic derangement 1

• Moderate hyperglycemia (A1C 8.5-10%) with symptoms:

  • Begin with basal insulin while initiating metformin 1
  • Starting dose: 10 units or 0.1-0.2 units/kg once daily 2

• Mild hyperglycemia (A1C <8.5%) without symptoms:

  • Consider non-insulin options first (metformin) 1
  • Add basal insulin if glycemic targets not achieved 1

For Critical Care Patients:

• Continuous intravenous insulin infusion is recommended for achieving glycemic goals and avoiding hypoglycemia 1, 3
  • Begin with priming dose of regular insulin (0.1 units/kg) as IV bolus 3
  • Follow with continuous IV insulin at 0.1 units/kg/hour 3
  • Target glucose reduction of 50-75 mg/dL per hour 3

Intensification of Insulin Therapy

When basal insulin alone is insufficient to achieve glycemic targets:

1. Add prandial (mealtime) insulin 1:

   • Start with one dose at largest meal (4 units or 10% of basal dose) 1
   • Options include rapid-acting analogs (aspart, lispro, glulisine) or regular human insulin 1, 2
   • Regular insulin should be administered 30 minutes before meals 2

2. Progress to basal-bolus regimen if needed 1:

   • Total daily insulin dose: 0.3-0.5 units/kg for insulin-naive patients 2
   • 50% as basal insulin, 50% as prandial insulin divided into three doses 2
   • Adjust doses based on blood glucose monitoring 1, 2

3. Consider premixed insulin in select cases 1:

   • Option for patients who cannot manage multiple daily injections 1
   • Typically 2/3 given before breakfast, 1/3 before dinner 1
   • Higher risk of hypoglycemia compared to basal-bolus regimens 2

Special Considerations

• Type 1 diabetes: Always requires basal-bolus insulin regimen; never hold basal insulin 1
• Steroid-induced hyperglycemia: Consider NPH insulin in the morning for steroid-induced hyperglycemia 1
• Renal impairment: Use lower insulin doses (reduced by 10-20%) 1, 2
• Elderly patients: Start with lower doses and titrate more cautiously 2
• Hospitalized patients: Avoid sliding scale insulin alone; use basal-bolus approach 1, 2

Common Pitfalls to Avoid

• Delaying insulin therapy when indicated by severe hyperglycemia or catabolic features 3
• Using sliding scale insulin alone without basal insulin (except for mild hyperglycemia) 1, 2
• Failing to adjust insulin doses based on blood glucose monitoring 1, 2
• Holding basal insulin in patients with type 1 diabetes 1
• Not considering hypoglycemia risk when selecting insulin regimens 1, 2

Advantages of Modern Insulin Analogs

• Basal insulin analogs (glargine, detemir, degludec) have lower within-subject variability and reduced hypoglycemia risk compared to NPH insulin 4, 5, 6
• Rapid-acting insulin analogs (lispro, aspart) better target postprandial glucose excursions 7
• Insulin detemir may be associated with less weight gain compared to NPH insulin 4, 8

Human insulin products remain effective and may be more cost-effective options for many patients, especially when financial considerations are important 6.