What is the recommended management approach for hyperglycaemia in hospitalised patients?

Hyperglycaemia Management in Hospitalised Patients

Target Glucose Ranges

Insulin therapy should be initiated when blood glucose persistently exceeds 180 mg/dL on two separate measurements, with a target range of 140-180 mg/dL for most critically ill and non-critically ill patients. 1

• More stringent targets of 110-140 mg/dL may be appropriate for selected stable patients (e.g., post-surgical, cardiac surgery) only if achievable without significant hypoglycemia 1
• For non-critically ill patients with new hyperglycemia, a target range of 100-180 mg/dL is acceptable 1
• Avoid aggressive targets below 110 mg/dL, as the NICE-SUGAR trial demonstrated 10-15 fold greater hypoglycemia rates and increased mortality (27.5% vs 25%) with intensive glycemic control 1

Critical Care Setting

Continuous intravenous insulin infusion is the most effective method for achieving glycemic goals in critically ill patients. 1

• Administer IV insulin using validated written or computerized protocols that allow predefined adjustments based on glycemic fluctuations 1
• Target glucose range: 140-180 mg/dL 1
• Monitor blood glucose every 30 minutes to 2 hours during IV insulin therapy 1
• For diabetic ketoacidosis (DKA) and hyperglycemic hyperosmolar state (HHS), use continuous IV insulin following fixed-rate or variable-rate protocols 1
• Mild uncomplicated DKA can be managed with subcutaneous rapid-acting insulin every 1-2 hours 1

Non-Critical Care Setting

Insulin Regimen Selection

Basal-bolus insulin regimens are preferred for non-critically ill patients with good oral intake, while basal insulin plus correction doses are recommended for those with poor or no oral intake. 1, 2

For Patients with Good Oral Intake:

Mild Hyperglycemia (BG <200 mg/dL):

• Consider low-dose basal insulin (0.1-0.2 units/kg/day) or oral antidiabetic agents 1
• Add correction doses with rapid-acting insulin before meals or every 6 hours 1

Moderate Hyperglycemia (BG 201-300 mg/dL):

• Start basal insulin at 0.2-0.3 units/kg/day 1
• Add correction doses with rapid-acting insulin before meals 1

Severe Hyperglycemia (BG >300 mg/dL):

• Implement basal-bolus regimen: reduce home insulin total daily dose (TDD) by 20% or start 0.3 units/kg/day, giving half as basal and half as bolus insulin 1
• For insulin-naive patients with severe hyperglycemia, start 0.3-0.5 units/kg/day as TDD 1

For Patients with Poor or No Oral Intake:

• Basal insulin alone with correction doses every 6 hours 1
• Never withhold basal insulin completely, especially in type 1 diabetes 1

High-Risk Populations Requiring Dose Reduction:

• Elderly patients (>65 years): use 0.1-0.25 units/kg/day 1
• Renal failure: reduce doses by 50% for type 2 diabetes with CKD Stage 5, or 35-40% for type 1 diabetes 3
• Poor oral intake: reduce starting doses to 0.15 units/kg/day 1
• Patients on high-dose home insulin (≥0.6 units/kg/day): reduce TDD by 20% upon admission 1

Glucose Monitoring Protocol

Point-of-care glucose monitoring frequency depends on nutritional status and insulin regimen. 1

• Patients eating meals: check before each meal 1
• Patients not eating (NPO): check every 4-6 hours 1
• Patients on IV insulin: check every 30 minutes to 2 hours 1

Oral Antidiabetic Medications

Insulin is the preferred treatment for hyperglycemia in most hospitalized patients, but certain oral agents may be continued in specific circumstances. 1

Metformin:

• Continue unless contraindicated (eGFR <30 mL/min, sepsis, shock, renal or liver failure, risk of lactic acidosis) 1, 4
• Discontinue in patients at risk for lactic acidosis 4

DPP-4 Inhibitors:

• May be continued in non-critically ill patients with mild-to-moderate hyperglycemia 1

Sulfonylureas:

• Discontinue due to sustained hypoglycemia risk, especially with inconsistent oral intake 5

Critical Threshold: Avoiding Overbasalization

When basal insulin exceeds 0.5 units/kg/day without achieving glycemic targets, add prandial insulin rather than continuing to escalate basal insulin alone. 1, 3

Clinical Signals of Overbasalization:

• Basal insulin dose >0.5 units/kg/day 1, 3
• Bedtime-to-morning glucose differential ≥50 mg/dL 1, 3
• Hypoglycemia episodes 1, 3
• High glucose variability 1, 3

Adding Prandial Insulin:

• Start with 4 units of rapid-acting insulin before the largest meal, or use 10% of basal dose 1, 3
• Titrate by 1-2 units or 10-15% every 3 days based on postprandial glucose 1, 3

Hypoglycemia Prevention and Management

Every hospital must implement a standardized hypoglycemia protocol. 1, 4

• Treat blood glucose ≤70 mg/dL with 15 grams of fast-acting carbohydrate 1, 4
• Recheck in 15 minutes and repeat treatment if needed 4
• Document all hypoglycemic episodes in the medical record 1, 4
• Review and adjust insulin regimen after any glucose <70 mg/dL 1, 4
• If hypoglycemia occurs without clear cause, reduce insulin dose by 10-20% immediately 1, 3

Discharge Planning

Medication reconciliation 1-2 days before discharge is essential for safe transition. 4, 5

• Resume oral agents 1-2 days before discharge to assess glycemic response 4, 5
• Measure HbA1c at admission to guide discharge planning 4, 2
• Patients with HbA1c >10% should be discharged on basal-bolus insulin or combination of oral agents plus 80% of hospital basal insulin dose 4
• Communicate with primary care physician regarding discharge regimen 6

Common Pitfalls to Avoid

Sliding scale insulin as monotherapy is explicitly condemned and should never be used. 1, 6, 7

• Sliding scale treats hyperglycemia reactively rather than preventing it, leading to dangerous glucose fluctuations 6, 7
• Only 38% of patients on sliding scale alone achieve mean glucose <140 mg/dL versus 68% with basal-bolus therapy 1
• Use correction insulin only as an adjunct to scheduled basal-bolus therapy, never as monotherapy 1, 6

Never withhold basal insulin in type 1 diabetes patients, even when NPO. 1

• Implement policies and electronic health record alerts to prevent basal insulin from being held during care transitions 1

Avoid premixed insulin regimens in hospitalized patients. 1

• Randomized trials show significantly increased hypoglycemia rates with premixed insulin compared to basal-bolus regimens 1

Do not delay insulin initiation in patients failing oral medications. 5, 3

• Prolonged hyperglycemia exposure increases complication risk 5, 3