What is the management for severe hyperglycemia?

Management of Severe Hyperglycemia (Blood Glucose 30.1 mmol/L)

Severe hyperglycemia with a blood glucose of 30.1 mmol/L requires immediate treatment with continuous insulin infusion therapy, which is the preferred regimen for hyperglycemic crises and critically ill patients. 1

Initial Assessment and Management

1. Evaluate for hyperglycemic crisis:

   • Check for signs of diabetic ketoacidosis (DKA): fruity breath odor, nausea, vomiting, abdominal pain, dehydration
   • Check for hyperosmolar hyperglycemic state (HHS): severe dehydration, altered mental status
   • Laboratory assessment: electrolytes, anion gap, ketones, osmolality 2

2. Initiate continuous insulin infusion therapy:

   • Start IV insulin infusion following institutional protocol
   • Target glucose range: 7.8-10.0 mmol/L (140-180 mg/dL) for most patients 1, 3
   • Monitor glucose levels hourly until stable 1

3. Address fluid and electrolyte imbalances:

   • Correct hypovolemia with IV fluids (typically normal saline)
   • Monitor potassium levels closely as hypokalaemia is common (about 50%) during treatment 1
   • Potassium supplementation may be required to prevent arrhythmias 4

Special Considerations

• For patients with ischemic events (MI or stroke): Rapid glucose control is warranted but avoid intensive lowering that may increase hypoglycemia risk 1
• For patients with renal insufficiency: Lower insulin doses are typically required 3
• For patients with residual renal function: Monitor for worsening hypovolemia during insulin treatment 5

Transition to Subcutaneous Insulin

Once the patient is stabilized (typically after 4-6 hours of stable glucose readings), transition to subcutaneous insulin:

1. Calculate daily insulin requirements:

   • Based on the average insulin infusion rate over the previous 12 hours
   • Example: If average rate is 1.5 units/hour, estimated daily dose would be 36 units/24 hours 1

2. Distribute insulin appropriately:

   • 50% as basal insulin and 50% as prandial insulin 3
   • For patients with new-onset diabetes and severe hyperglycemia, initial dose of 0.3-0.4 units/kg/day 3

3. Administer basal insulin 2-4 hours before discontinuing IV insulin to ensure adequate overlap 3

Monitoring and Ongoing Management

• Monitor blood glucose frequently to avoid hypoglycemia
• Watch for signs of hypoglycemia: sweating, drowsiness, dizziness, tremor, hunger 4
• Severe hypoglycemia (<3.0 mmol/L or 54 mg/dL) requires immediate intervention 3
• Adjust insulin doses every 2-3 days based on glucose patterns 3

Special Circumstances

• In specific circumstances, such as severe hyperglycemia (HbA1c >10%) with weight loss or ketosis, insulin may be the preferred long-term agent for glucose control 1
• For patients with type 2 diabetes, once stabilized, consider adding agents with complementary mechanisms of action that provide cardiorenal protection or weight reduction 1

Pitfalls to Avoid

1. Sliding scale insulin alone is inadequate for managing severe hyperglycemia and is associated with poor glycemic control 1
2. Neglecting potassium monitoring can lead to life-threatening hypokalemia during insulin treatment 1, 4
3. Failing to identify and treat the underlying cause of hyperglycemia (infection, medication, etc.) 6
4. Therapeutic inertia in transitioning from IV to subcutaneous insulin or intensifying insulin therapy 1
5. Abrupt discontinuation of IV insulin without proper overlap with subcutaneous insulin 3

By following this structured approach to managing severe hyperglycemia, you can effectively reduce blood glucose levels while minimizing the risk of complications and improving patient outcomes.