What are the types of insulin therapies for in-patients?

Types of Insulin Therapies for Hospitalized Patients

For non-critically ill hospitalized patients with good oral intake, use a basal-bolus-correction insulin regimen; for those with poor or no oral intake, use basal insulin plus correction insulin only. 1

Critical Care Setting

Continuous intravenous insulin infusion is the preferred and most effective method for managing hyperglycemia in critically ill patients. 1, 2

• IV insulin should be administered using validated written or computerized protocols that allow predefined adjustments based on glycemic fluctuations 1, 3
• Target blood glucose range of 140-180 mg/dL for most ICU patients 3, 2
• More stringent goals of 110-140 mg/dL may be appropriate for select stable patients 3
• Requires frequent bedside glucose monitoring every 30 minutes to 2 hours 2

Non-Critical Care Setting: Patients Eating Regular Meals

A basal-bolus-correction insulin regimen is the preferred treatment for non-critically ill hospitalized patients with good nutritional intake. 1, 4

Components of Basal-Bolus Regimen:

• Basal insulin: Long-acting insulin (glargine, detemir) given once daily to provide background insulin coverage 4
• Prandial (bolus) insulin: Rapid-acting insulin (lispro, aspart, glulisine) given before each meal to cover carbohydrate intake 1, 4
• Correction insulin: Additional rapid-acting insulin given to correct elevated glucose levels 1, 4

Dosing Strategy:

• Start with total daily dose of 0.3-0.5 units/kg/day for insulin-naive patients 4, 2
• Allocate 50% to basal insulin and 50% to prandial insulin divided across three meals 4, 2
• For severe hyperglycemia (>300 mg/dL), use 0.3 units/kg/day total daily dose 4
• For moderate hyperglycemia (201-300 mg/dL), start with 0.2-0.3 units/kg/day 4
• Insulin injections should align with meals, with point-of-care glucose testing performed immediately before meals 1

Non-Critical Care Setting: Patients with Poor or No Oral Intake (NPO)

Basal insulin plus correction insulin only is the preferred treatment for non-critically ill hospitalized patients with poor oral intake or those who are NPO. 1, 4

• Use lower starting dose of 0.1-0.25 units/kg/day given mainly as basal insulin 4, 2
• Add rapid-acting insulin as correctional coverage for glucose >180 mg/dL 4
• If oral intake is poor, administer rapid-acting insulin immediately after the patient eats with dose adjusted for amount ingested 1

Special Considerations for Type 1 Diabetes

All hospitalized patients with type 1 diabetes require an insulin regimen with basal and correction components at minimum, with addition of prandial insulin if eating. 1, 2

• Dosing insulin based solely on premeal glucose levels does not account for basal insulin requirements or caloric intake, increasing risk of both hypoglycemia and hyperglycemia 1
• Basal insulin must never be discontinued in type 1 diabetes patients 2
• Patients with renal insufficiency should be treated with lower doses 1, 2

Transitioning from IV to Subcutaneous Insulin

Administer subcutaneous basal insulin 2-4 hours before discontinuing IV insulin infusion to prevent rebound hyperglycemia. 1, 3, 2

• Calculate dose at 60-80% of the daily IV infusion dose 1
• Base calculation on insulin infusion rate during last 6-8 hours when stable glycemic goals were achieved 1, 3
• Use of a transition protocol is associated with less morbidity and lower costs of care 1

Critical Pitfalls to Avoid

Sliding Scale Insulin Alone is Strongly Discouraged

Prolonged sole use of sliding scale insulin (SSI) in the inpatient hospital setting is strongly discouraged and should never be used as the only regimen. 1, 3, 4

• Basal-bolus treatment improved glycemic control and reduced hospital complications compared with SSI in general surgery patients with type 2 diabetes 1, 5
• SSI results in poorer glycemic control with mean daily blood glucose differences of 23-58 mg/dL compared to basal-bolus regimens 5
• SSI increases both hypoglycemia and hyperglycemia risk 3, 4

Premixed Insulin Not Recommended

Premixed insulin formulations (70/30 NPH/regular) are not routinely recommended for in-hospital use. 1, 4

• Premixed insulin showed comparable glycemic control but significantly increased hypoglycemia (threefold higher rate) compared to basal-bolus therapy 1, 4
• Fixed ratios cannot be adjusted for variable oral intake 4

SGLT2 Inhibitors Should Be Avoided

SGLT2 inhibitors should be discontinued 3-4 days before surgery and avoided during hospitalization. 1, 3

• Should be avoided in cases of severe illness, ketonemia, ketonuria, and during prolonged fasting 1
• Not recommended for routine in-hospital use until safety and effectiveness are established 1

Hypoglycemia Prevention

A standardized hospital-wide hypoglycemia management protocol must be implemented. 1, 3, 2

• Treatment regimens should be reviewed and adjusted when blood glucose falls below 70 mg/dL 1, 2
• 84% of patients with severe hypoglycemia (<40 mg/dL) had a prior episode of hypoglycemia (<70 mg/dL) during the same admission 1
• All hypoglycemic episodes should be documented in the medical record and tracked 1, 2

Insulin Administration Considerations

• Insulin pens may be safely used in the hospital setting but must be strictly labeled "For single patient use only" per FDA warning 1, 2
• Human insulin and analog insulins provide similar glycemic control in the hospital setting 1, 2
• For concentrated insulin (U-200, U-300, U-500), ensure correct dosing by utilizing individual pen and cartridge for each patient with meticulous pharmacist supervision 1