What is the best approach for managing inpatient hyperglycemia?

Inpatient Hyperglycemia Management

Critical Care Setting

For critically ill patients, initiate continuous intravenous insulin infusion when blood glucose exceeds 180 mg/dL, targeting a glucose range of 140-180 mg/dL. 1, 2

• Start IV insulin at a threshold of ≥180 mg/dL (checked on two occasions) 1
• Use validated written or computerized protocols that allow predefined adjustments based on glycemic fluctuations and current insulin infusion rates 1, 2
• The short half-life of IV insulin (<15 minutes) enables rapid dose titration with changing clinical status 1, 2
• Avoid subcutaneous insulin in critically ill patients, particularly during hypotension or shock 1, 2
• More stringent targets of 110-140 mg/dL may be considered for select patients (cardiac surgery, acute ischemic cardiac or neurological events) only if achievable without significant hypoglycemia 1
• Never target euglycemia (80-110 mg/dL) as this substantially increases iatrogenic hypoglycemia risk and mortality 1

Non-Critical Care Setting

For non-critically ill patients with adequate oral intake, use a basal-bolus-correction insulin regimen targeting blood glucose 100-180 mg/dL, with pre-meal targets <140 mg/dL. 1, 2

Blood Glucose Monitoring

• Monitor all patients with known diabetes or admission blood glucose >140 mg/dL 2
• Check blood glucose before meals and at bedtime for patients eating 1
• Check every 4-6 hours for patients not eating 1

Insulin Regimen for Patients with Adequate Oral Intake

Start with basal-bolus-correction regimen:

• Total daily dose (TDD): 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, 2
• Add correction doses of rapid-acting insulin for blood glucose >180 mg/dL 2
• Sliding scale insulin alone is strongly discouraged and should not be used as the single regimen 1

Insulin Regimen for Patients with Poor or No Oral Intake

Use basal insulin plus correction doses:

• Single dose of basal insulin: 0.1-0.25 units/kg/day 1, 2
• Add correction doses of rapid-acting insulin before meals or every 6 hours if NPO 2

High-Risk Patients Requiring Dose Reduction

Reduce insulin doses to prevent hypoglycemia in:

• 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
• High-dose home insulin (≥0.6 units/kg/day): Reduce total daily dose by 20% 2

Non-Insulin Medications

DPP-4 inhibitors (sitagliptin) alone or with basal insulin represent a safe alternative for non-cardiac patients with type 2 diabetes and mild-to-moderate hyperglycemia. 1, 2

• Dose sitagliptin 50-100 mg daily based on kidney function 1, 2
• Results in similar glycemic control as basal-bolus regimens with lower hypoglycemia risk 1, 2
• Avoid metformin in patients at risk for lactic acidosis 1
• Reduce metformin dose if eGFR 30-45 mL/min per 1.73 m² 2
• Discontinue metformin before iodinated contrast procedures in patients with eGFR <60 mL/min, liver disease, alcoholism, or acute heart failure 2
• Do not use sulfonylureas due to hypoglycemia risk and inability to rapidly adjust doses 2

Hypoglycemia Management

Every hospital must implement a standardized hypoglycemia management protocol. 1, 2

• Define moderate hypoglycemia as blood glucose <70 mg/dL 1, 2
• Define severe hypoglycemia as blood glucose <54 mg/dL or requiring assistance 1, 2
• Treat conscious patients with oral carbohydrate or glucose 1
• Use intravenous glucose for patients taking nothing by mouth 1
• Use intranasal or subcutaneous glucagon for those without intravenous access 1
• Review and modify treatment regimens after hypoglycemia episodes to prevent recurrence 1
• The incidence of mild hypoglycemia with basal-bolus regimens is 12-30% in controlled settings 1

Glucocorticoid-Induced Hyperglycemia

Patients on steroids require specific insulin adjustments:

• For patients without diabetes: Consider a single morning dose of NPH 2
• For 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

Discharge Planning

Begin transition to outpatient regimens 1-2 days before discharge, with adjustments based on HbA1c at admission. 1, 2

• Resume home oral medications 1-2 days before discharge if suspended during hospitalization 1, 2
• Obtain HbA1c if not available from previous 3 months 2
• For HbA1c <7%: Resume pre-admission regimen 1
• For HbA1c 7-9%: Add small dose of basal insulin or intensify pre-admission regimen 1
• For HbA1c >10%: Discharge on basal-bolus regimen or previous oral agents plus 80% of hospital basal insulin dose 1, 2
• Schedule outpatient follow-up within 1 week to 1 month 1, 2
• Provide discharge education on medications, blood glucose monitoring, hypoglycemia prevention, and nutrition 1
• Assess self-management capabilities prior to discharge 1
• Provide insulin and monitoring materials (test strips, lancets) at discharge 1

Common Pitfalls to Avoid

• Never use sliding scale insulin as monotherapy - it results in undesirable hypoglycemia and hyperglycemia with increased risk of hospital complications 1
• Avoid rotating injection sites into areas of lipodystrophy or localized cutaneous amyloidosis - this can cause hyperglycemia, and sudden changes to unaffected areas can cause hypoglycemia 3
• Do not mix rapid-acting insulin analogs with other insulins 3
• Increase blood glucose monitoring frequency during any insulin regimen changes 3