How are insulin adjustments made for patients with uncontrolled glucose levels?

Insulin Adjustments for Patients with Uncontrolled Glucose Levels

Insulin adjustments for patients with uncontrolled glucose should follow a systematic approach based on blood glucose patterns, with basal insulin starting at 10 units or 0.1-0.2 units/kg and titration based on self-monitoring of blood glucose (SMBG) levels. 1

Initial Insulin Therapy Approach

Starting Basal Insulin

• Begin with basal insulin at 10 units or 0.1-0.2 units/kg/day, depending on the degree of hyperglycemia 1
• Typically prescribed with metformin and possibly one additional non-insulin agent 1
• Set fasting plasma glucose (FPG) goals and choose an evidence-based titration algorithm 1
• Increase by approximately 2 units every 3 days to reach FPG goal without hypoglycemia 1
• If hypoglycemia occurs, determine the cause; if no clear reason is found, reduce dose by 10-20% 1

When to Consider Insulin Initiation

• Consider starting insulin when A1C ≥9% 1
• Start immediately when blood glucose ≥300-350 mg/dL (16.7-19.4 mmol/L) or A1C ≥10-12%, especially if symptomatic 1
• In cases of severe hyperglycemia with ketosis or unintentional weight loss, basal insulin plus mealtime insulin is the preferred initial regimen 1

Adjusting Insulin Therapy When Goals Are Not Met

When Basal Insulin Is Insufficient

• If basal insulin has been titrated to acceptable fasting blood glucose but A1C remains above target, advance to combination injectable therapy 1
• Options include:
  1. Adding a GLP-1 receptor agonist 1
  2. Adding mealtime insulin (prandial insulin) 1
  3. Switching to twice-daily premixed insulin 1

Adding Prandial Insulin

• Start with one dose with the largest meal or meal with greatest postprandial glucose excursion 1
• Initial dose: 4 units per day or 10% of basal insulin dose 1
• Increase dose by 1-2 units or 10-15% based on postprandial glucose readings 1
• If A1C <8%, consider lowering the basal dose by 4 units or 10% when adding prandial insulin 1
• For hypoglycemia, determine cause; if no clear reason, lower corresponding dose by 10-20% 1

Full Basal-Bolus Regimen

• When stepping up to multiple daily injections, consider the following distribution 1:
  • Total insulin dose: divide as 50% basal and 50% prandial, with prandial insulin split evenly between meals 1
  • For premixed insulin plans: typically 2/3 before breakfast and 1/3 before dinner 1

Monitoring and Adjusting Insulin Therapy

Self-Monitoring of Blood Glucose (SMBG)

• Equipping patients with an algorithm for self-titration based on SMBG improves glycemic control 1
• Adjustments to both basal and prandial insulins should be based on prevailing blood glucose levels 1
• Pattern control requires understanding the pharmacodynamic profile of each insulin formulation 1

Continuous Glucose Monitoring (CGM)

• CGM provides real-time insights into glucose dynamics and trends, which can guide more precise insulin adjustments 2
• When using CGM data, patients often make larger insulin adjustments than commonly recommended:
  • For rapidly rising glucose (>3 mg/dL/minute), patients may increase correction bolus by up to 140% 3
  • For rapidly falling glucose (>3 mg/dL/minute), patients typically reduce dose by 42% 3

Special Considerations

Hypoglycemia Management

• If hypoglycemia occurs, determine the cause and reduce the insulin dose by 10-20% if no clear reason is identified 1
• Patients should carry at least 15g of carbohydrate to treat hypoglycemic episodes 1
• Family members should be instructed in glucagon use for severe hypoglycemia 1

Insulin Administration Sites

• Rotation of injection sites is important to prevent lipohypertrophy or lipoatrophy 1
• Systematic rotation within one area (e.g., abdomen) is recommended rather than rotating between different areas 1
• Absorption rates differ by site: abdomen (fastest) > arms > thighs > buttocks 1
• Exercise increases absorption rates from injection sites 1

During Illness

• Continue insulin even when the patient is unable to eat or is vomiting 1
• More frequent SMBG may be required during illness, travel, or changes in routine 1

Adjustments in Hospital Settings

For Critically Ill Patients

• Use intravenous insulin infusion with a starting threshold of no higher than 180 mg/dL 1
• Maintain glucose levels between 140-180 mg/dL (7.8-10.0 mmol/L) 1
• Lower targets (120-140 mg/dL) may be appropriate in select patients 1

For Non-Critically Ill Patients

• Target premeal glucose <140 mg/dL (7.8 mmol/L) 1
• Target random blood glucose <180 mg/dL (10.0 mmol/L) 1
• Reassess insulin regimen if blood glucose falls below 100 mg/dL (5.6 mmol/L) 1
• Modify regimen when blood glucose values are <70 mg/dL (3.9 mmol/L) 1

By following these structured approaches to insulin adjustment, clinicians can effectively manage uncontrolled glucose levels while minimizing the risk of hypoglycemia and optimizing patient outcomes.