What to do for a patient with two blood glucose readings of hyperglycemia (elevated blood sugar)?

Management of Severe Hyperglycemia (Blood Glucose of 500 mg/dL)

A blood glucose reading of 500 mg/dL requires immediate intervention with intravenous insulin therapy, aggressive fluid resuscitation, and electrolyte monitoring to prevent life-threatening complications. 1, 2

Initial Assessment and Management

• Begin isotonic saline (0.9% NaCl) at 15-20 mL/kg/hr in the first hour to restore circulatory volume and tissue perfusion 2
• Start continuous intravenous regular insulin at 0.1 units/kg/hr after initial fluid resuscitation has begun 1, 2
• If glucose does not fall by 50-75 mg/dL in the first hour, double the insulin infusion rate 2
• Monitor blood glucose every 1-2 hours until stable 2
• Evaluate for precipitating factors such as infection, medication non-adherence, or new-onset diabetes 2

Fluid and Electrolyte Management

• After the first hour, continue fluid replacement based on hemodynamic status, typically at 4-14 mL/kg/hr 2
• Monitor serum potassium levels every 2-4 hours as insulin therapy can cause hypokalemia 2
• Begin potassium replacement when serum levels fall below 5.2 mEq/L, provided the patient has adequate urine output 2
• Monitor electrolytes, blood urea nitrogen, creatinine, and venous pH every 2-4 hours 2

Transitioning to Subcutaneous Insulin

• Once blood glucose reaches 200-250 mg/dL, add dextrose to IV fluids while continuing insulin infusion to prevent hypoglycemia 1, 2
• Continue insulin infusion until hyperglycemic crisis resolves (pH >7.3, bicarbonate ≥18 mEq/L, and anion gap normalized) 2
• For non-critically ill patients, transition to a basal-bolus insulin regimen once the acute crisis is resolved 1

Diagnostic Considerations

• Measure β-hydroxybutyrate in blood to assess for diabetic ketoacidosis (DKA), which is preferred over urine ketones 2
• Check arterial pH and bicarbonate levels to determine if DKA is present 2
• Obtain hemoglobin A1C to differentiate between new-onset diabetes, uncontrolled known diabetes, or stress hyperglycemia 3

Specific Clinical Scenarios

For Diabetic Ketoacidosis

• Continue insulin infusion until DKA resolves (pH >7.3, bicarbonate ≥18 mEq/L, and anion gap normalized) 2
• Administer subcutaneous basal insulin 2-4 hours before discontinuing IV insulin to prevent recurrence of ketoacidosis 2

For Hyperosmolar Hyperglycemic State (HHS)

• More aggressive fluid resuscitation may be needed as dehydration is typically more severe 4
• Monitor for signs of cerebral edema, particularly when glucose levels decrease rapidly 2

For Steroid-Induced Hyperglycemia

• If the patient is on glucocorticoids, consider higher insulin doses as steroid-induced hyperglycemia is often more resistant to treatment 1
• For patients receiving high-dose dexamethasone, multiple-dose insulin therapy initiated at 1–1.2 U/kg per day (distributed as 25% basal and 75% prandial) may be effective 1

Monitoring for Complications

• Assess for signs of cerebral edema, particularly in younger patients (headache, altered mental status, seizures, bradycardia) 2
• Monitor for hypoglycemia during treatment, especially when transitioning between insulin regimens 5
• Watch for hypokalemia, which can lead to respiratory paralysis, ventricular arrhythmia, and death 5

Discharge Planning and Prevention

• Review sick-day management with patients before discharge 2
• Educate patients on monitoring blood glucose and ketones when blood glucose is >300 mg/dL 2
• Schedule follow-up appointment before discharge 2

Common Pitfalls to Avoid

• Using only sliding scale insulin, which is strongly discouraged for inpatient management 1
• Failing to identify and treat the underlying cause of hyperglycemia 2
• Discontinuing insulin too early when transitioning from IV to subcutaneous administration 2
• Inadequate fluid resuscitation, which can worsen hyperglycemia and increase risk of complications 2

Remember that severe hyperglycemia (500 mg/dL) represents a medical emergency that requires prompt intervention to prevent life-threatening complications. The management approach should focus on insulin therapy, fluid resuscitation, and identification of the underlying cause.