What is the recommended approach for inpatient management of hyperglycemia?

Inpatient Management of Hyperglycemia

Critical Care Setting (ICU)

Continuous intravenous insulin infusion is the preferred treatment for critically ill patients with hyperglycemia, targeting blood glucose 140-180 mg/dL. 1

• Start IV insulin when blood glucose exceeds 180 mg/dL in critically ill patients 1
• Use validated written or computerized protocols that allow predefined adjustments based on glycemic fluctuations and current insulin infusion rates 1
• Avoid subcutaneous insulin in critically ill patients, particularly during hypotension or shock 1
• The short half-life of IV insulin (<15 minutes) allows rapid dose titration with changing clinical status 1

Common Pitfall: Targeting euglycemia (80-110 mg/dL) substantially increases iatrogenic hypoglycemia risk and is strongly discouraged 1

Non-Critical Care Setting

Blood Glucose Monitoring and Targets

All patients with known diabetes or admission blood glucose >140 mg/dL require blood glucose monitoring. 1

• Target blood glucose 100-180 mg/dL for non-critically ill patients 1
• Pre-meal targets should be <140 mg/dL 1
• Monitor blood glucose before meals and at bedtime 1

Insulin Regimen Selection Based on Oral Intake

For patients with adequate oral intake, a basal-bolus-correction regimen is the preferred treatment. 1

Basal-Bolus Regimen (Good Oral Intake):

• Starting total daily dose: 0.3-0.5 units/kg for insulin-naive patients or those on low-dose insulin 2
• Divide as: 50% basal insulin (glargine or detemir) once daily + 50% prandial insulin (lispro, aspart, or glulisine) divided before three meals 1
• Add correction doses of rapid-acting insulin for blood glucose >180 mg/dL 1

For patients with poor or no oral intake, basal insulin plus correction doses is preferred. 1

Basal-Plus Regimen (Poor/No Oral Intake):

• Single dose of basal insulin: 0.1-0.25 units/kg/day 1
• Add correction doses of rapid-acting insulin before meals or every 6 hours if NPO 1
• This approach reduces hypoglycemia risk in patients with decreased oral intake 1

Special Populations Requiring Lower Doses

High-risk patients require reduced insulin doses to prevent hypoglycemia. 2

• Elderly patients (>65 years): Start at 0.1-0.15 units/kg/day 1, 2
• Renal failure (eGFR <30 mL/min): Reduce doses by 20% 2
• Poor oral intake: Use 0.1-0.25 units/kg/day 2
• Patients on high-dose home insulin (≥0.6 units/kg/day): Reduce total daily dose by 20% to prevent hypoglycemia 2

What NOT to Do

Sliding scale insulin (SSI) alone is strongly discouraged as monotherapy in patients with established diabetes. 1, 3

• SSI alone results in inferior glycemic control and increased hospital complications compared to basal-bolus regimens 1, 3
• The risk of hypoglycemia with basal-bolus insulin is 4-6 times higher than SSI, but overall glycemic control is superior 1
• Limited exception: SSI alone may be acceptable only for patients without diabetes who have mild stress hyperglycemia 3

Premixed insulin (70/30) is not recommended in the hospital due to unacceptably high hypoglycemia rates. 1

Non-Insulin Medications

When Non-Insulin Agents May Be Appropriate

Recent evidence supports selective use of non-insulin medications in hospitalized patients with type 2 diabetes and mild-to-moderate hyperglycemia. 1

DPP-4 Inhibitors (Sitagliptin):

• May be used alone or with basal insulin in non-cardiac patients with type 2 diabetes 1
• Dose: 50-100 mg daily based on kidney function 1
• Results in similar glycemic control as basal-bolus regimens with lower hypoglycemia risk 1
• Particularly useful in elderly patients with mild-to-moderate hyperglycemia 1

Metformin:

Metformin should be discontinued in patients at risk for lactic acidosis. 1

• Contraindications: Sepsis, hypoxia, acute kidney injury, shock, significant renal impairment (eGFR <30 mL/min), liver failure 1
• Reduce dose if eGFR 30-45 mL/min per 1.73 m² 1
• Discontinue before iodinated contrast procedures in patients with eGFR <60 mL/min, liver disease, alcoholism, or acute heart failure 1
• In COVID-19 patients, metformin was associated with increased lactic acidosis (adjusted HR 4.46) 1

Sulfonylureas:

• Not recommended due to hypoglycemia risk and inability to rapidly adjust doses 1

Hypoglycemia Management

Every hospital must implement a standardized hypoglycemia management protocol. 1, 3

• Define moderate hypoglycemia as blood glucose <70 mg/dL 4
• Define severe hypoglycemia as blood glucose <54 mg/dL or requiring assistance 4
• Treat with oral carbohydrate or glucose for conscious patients 4
• The incidence of mild hypoglycemia with basal-bolus regimens is 12-30% in controlled settings 1, 3

Discharge Planning

Transition to outpatient regimens should begin 1-2 days before discharge. 1, 4

• Resume home oral medications 1-2 days before discharge if suspended during hospitalization 1
• Obtain HbA1c if not available from previous 3 months 1
• For patients with HbA1c >10%: Discharge on basal-bolus regimen or previous oral agents plus 80% of hospital basal insulin dose 1
• Schedule outpatient follow-up within 1 week to 1 month 4

Glucocorticoid-Induced Hyperglycemia

Patients on steroids require specific insulin adjustments. 2

• Patients without diabetes: Single morning dose of NPH may be appropriate 2
• Patients with diabetes: Add 0.1-0.3 units/kg/day glargine to usual insulin regimen, with doses determined by steroid dose and oral intake 2