Insulin Therapy

Introduction to Insulin Regimens

• The American Diabetes Association recommends against using sliding scale insulin alone for managing diabetes in hospitalized patients, as it is ineffective and should be replaced with basal-bolus insulin regimens, with a strong evidence base 1
• Basal-bolus insulin regimens are preferred due to their ability to improve glycemic control and reduce hospital complications compared to sliding scale insulin regimens, with a strong evidence base 1

Insulin Dosing and Administration

• Calculate total daily insulin dose at 0.3-0.5 units/kg/day for insulin-naive patients, as suggested by the European Association for the Study of Diabetes 2
• Basal insulin should be calculated at 0.3-0.5 units/kg/day and administered as long-acting insulin (glargine or detemir) once or twice daily, with a total daily dose (TDD) of 0.3-0.5 units/kg/day, divided into 50% basal insulin and 50% prandial insulin, for patients with adequate oral intake, as recommended by the American College of Clinical Endocrinologists and the American Diabetes Association 2, 3, 4, 5
• For patients with renal impairment, insulin doses should be reduced by 20-25%, as suggested by the European Association for the Study of Diabetes and the National Kidney Foundation 2
• Administer subcutaneous basal insulin 2-4 hours before discontinuing IV infusion, as recommended by the American College of Clinical Endocrinologists 1
• Convert to basal insulin at 60-80% of the daily infusion dose, according to the American Diabetes Association guidelines 1

Blood Glucose Monitoring and Targets

• For hospitalized patients who are eating, glucose monitoring should be performed before meals, according to the American Diabetes Association 1
• For patients not eating, monitoring every 4-6 hours is recommended, according to the American Diabetes Association 1
• Bedside glucose monitoring should be performed every 4-6 hours in hospitalized patients who are not eating, with more frequent monitoring for patients with variable glucose levels, as recommended by the American Diabetes Association 6, 7
• Target blood glucose range of 140-180 mg/dL is recommended for hospitalized patients, as suggested by the Society of Critical Care Medicine and the European Association for the Study of Diabetes 2, 8
• For elderly patients, a simplified approach may be used with less aggressive targets (90-150 mg/dL), as recommended by the American Geriatrics Society and the American Diabetes Association 9

Hypoglycemia Management

• Define hypoglycemia as blood glucose <3.9 mmol/L, and for mild-moderate hypoglycemia (3.0-3.9 mmol/L) in conscious patients, administer 15-20g oral carbohydrate and recheck blood glucose after 15 minutes 9
• For severe hypoglycemia (<3.0 mmol/L) or unconscious patients, administer IV dextrose 25g (50 mL of 50% solution) or glucagon 1mg IM/SC if IV access is not available, following the American Diabetes Association guidelines 9
• Implement a hypoglycemia protocol for all patients, defining hypoglycemia as blood glucose <70 mg/dL, and providing treatment guidelines for mild-moderate and severe hypoglycemia, as recommended by the American Diabetes Association 10

Correction Dosing for Hyperglycemia

• For blood glucose values above target, the American Diabetes Association recommends adding 2 units of rapid-acting insulin for values >13.9 mmol/L (>250 mg/dL) and 4 units for values >19.4 mmol/L (>350 mg/dL) 11
• The following tables outline the correction dosing for hyperglycemia:

9, 12

Rapid-Acting Insulin Characteristics

• Humalog (insulin lispro) is a rapid-acting insulin with onset within 5 minutes, peak action at 1-2 hours, and duration of 3-4 hours 13