How to administer insulin for severe hyperglycemia (blood sugar level of 380 mg/dL)?

Management of Severe Hyperglycemia (Blood Sugar 380 mg/dL)

For a blood sugar of 380 mg/dL, immediate insulin therapy should be initiated, preferably with rapid-acting insulin at a dose of 0.1 units/kg body weight as a subcutaneous injection, followed by appropriate basal insulin coverage. 1

Initial Assessment and Approach

• Evaluate for symptoms of hyperglycemia (polyuria, polydipsia, blurred vision)
• Check for signs of dehydration or ketosis/ketoacidosis
• Determine if this is a known diabetic patient or new presentation
• Rule out precipitating factors (infection, medication non-adherence, stress)

Immediate Management

For Non-Critical Outpatient Setting:

1. Rapid-Acting Insulin Administration:

   • Calculate dose: 0.1 units/kg body weight of rapid-acting insulin (insulin aspart, lispro, or glulisine)
   • For a 70 kg adult: approximately 7 units subcutaneously
   • Inject in abdomen, upper arms, or thighs 2
   • Expect blood glucose to decrease by approximately 50-80 mg/dL per hour

2. Hydration:

   • Encourage oral fluid intake if the patient is alert and not nauseated
   • Monitor for signs of dehydration

3. Follow-up Monitoring:

   • Recheck blood glucose in 1-2 hours
   • If glucose remains >300 mg/dL, consider additional correction dose

For Hospital/Emergency Setting:

1. For Blood Glucose >300 mg/dL:

   • Initiate insulin therapy immediately 1
   • Target glucose range of 140-180 mg/dL for most patients 1

2. Insulin Administration Options:

   • Intravenous insulin: For severe hyperglycemia or if patient has symptoms of diabetic ketoacidosis

     • Start at 0.1 units/kg/hour 3
     • Adjust based on hourly glucose measurements

   • Subcutaneous insulin: For stable patients

     • Rapid-acting insulin: 0.1 units/kg as correction dose
     • Consider basal-bolus regimen for ongoing management

3. Fluid Management:

   • IV fluids if patient is dehydrated (normal saline initially) 3
   • Monitor electrolytes, particularly potassium

Ongoing Management

Transition to Maintenance Therapy:

1. For Known Diabetic Patients:

   • Resume or adjust previous regimen
   • Consider basal-bolus insulin therapy if not already established
   • Basal insulin: 0.1-0.2 units/kg/day 1
   • Mealtime insulin: 0.05-0.1 units/kg per meal 1

2. For Newly Diagnosed Patients:

   • Consider starting with basal insulin at 10 units or 0.1-0.2 units/kg/day 1
   • Add mealtime insulin if needed
   • Consider GLP-1 receptor agonist before escalating to multiple daily insulin injections 1

Insulin Selection:

• Basal insulin options: glargine, detemir, degludec, or NPH 1
• Rapid-acting insulin options: aspart, lispro, or glulisine 2, 4
• Analogue insulins are preferred over regular human insulin due to faster onset and lower risk of hypoglycemia 2, 4

Important Considerations and Pitfalls

• Avoid aggressive correction: Too rapid correction can lead to hypoglycemia
• Monitor for hypoglycemia: Symptoms include dizziness, confusion, sweating, shakiness 2
• Ketone testing: Check for ketones in type 1 diabetes or when glucose >300 mg/dL 1
• Identify and treat underlying cause: Infection, medication non-adherence, dietary indiscretion
• Medication adjustments: Consider discontinuing sulfonylureas when initiating insulin therapy 1

Special Situations

• Suspected DKA: If ketones are present with glucose >380 mg/dL, more aggressive management with IV insulin and fluids is required 3
• Steroid-induced hyperglycemia: May require higher insulin doses and more frequent monitoring
• Critically ill patients: Target blood glucose ≤180 mg/dL, not lower than 110 mg/dL to avoid hypoglycemia 5, 6

Remember that insulin requirements may change based on the patient's response, and frequent blood glucose monitoring is essential for safe and effective management of severe hyperglycemia.