What is the initial workup and management for a patient presenting to the Emergency Department (ED) with hyperglycemia?

Initial Workup and Management of Hyperglycemia in the Emergency Department

For patients presenting with hyperglycemia in the Emergency Department, the initial workup should include blood glucose, venous blood gases, electrolytes, blood urea nitrogen (BUN), creatinine, calcium, phosphorous, and urine analysis STAT to assess severity and identify underlying causes.

Initial Assessment

Laboratory Evaluation

• Obtain immediately:
  • Blood glucose level
  • Venous blood gases
  • Complete electrolyte panel
  • BUN and creatinine
  • Calcium and phosphorous
  • Urinalysis 1
  • Consider beta-hydroxybutyrate (β-OHB) measurement for suspected DKA (preferred over nitroprusside method) 1

Clinical Evaluation

• Assess for:
  • Mental status changes
  • Signs of dehydration
  • Vital signs (particularly for hypotension, tachycardia)
  • Symptoms of hyperglycemic crisis (polyuria, polydipsia, nausea, vomiting)
  • Potential precipitating factors (infection, myocardial infarction, stroke) 1

Management Algorithm

1. Severity Classification

• Mild hyperglycemia: >180 mg/dL 2
• Severe hyperglycemia: >250 mg/dL, assess for symptoms of hyperglycemic crisis 2
• DKA: Glucose >250 mg/dL, pH <7.3, bicarbonate <15 mEq/L, presence of ketones 1
• HHS: Severe hyperglycemia, hyperosmolality, no significant ketoacidosis 1

2. Treatment Based on Severity

For Mild to Moderate Hyperglycemia (Non-critical patients)

• Target pre-meal glucose <140 mg/dL and random glucose <180 mg/dL 2
• Consider subcutaneous insulin therapy:
  • For mild DKA: "Priming" dose of regular insulin (0.4-0.6 units/kg), half as IV bolus and half as subcutaneous/intramuscular injection 1
  • Follow with 0.1 unit regular insulin subcutaneously/intramuscularly hourly 1

For Severe Hyperglycemia or Hyperglycemic Crisis

• Fluid Resuscitation:

  • Begin with isotonic saline at 1.5 times the 24-hour maintenance requirements (approximately 5 ml/kg/hr) 1
  • Do not exceed twice the maintenance requirement 1

• Insulin Therapy:

  • For critically ill patients or those with DKA/HHS: Continuous IV insulin infusion is standard of care 1
  • Initial dose of IV regular insulin: 0.5 U/hr, adjusted to maintain blood glucose 100-160 mg/dL 3
  • Monitor blood glucose hourly until stable 2

• Electrolyte Management:

  • Potassium replacement: Use solution with 1/3 KPO₄ and 2/3 KCl or K-acetate 1
  • Monitor serum electrolytes every 2-4 hours during acute treatment 1
  • Phosphate replacement may be considered for patients with cardiac dysfunction, anemia, respiratory depression, or serum phosphate <1.0 mg/dL 1

• Bicarbonate Therapy:

  • Generally not recommended for DKA 1
  • May be beneficial only in patients with pH <6.9 1

3. Monitoring During Treatment

• Check blood glucose every 1-2 hours until stable 2
• Monitor electrolytes, BUN, creatinine every 2-4 hours 1
• Follow venous pH and anion gap to monitor resolution of acidosis 1
• For DKA, criteria for resolution include:
  • Glucose <200 mg/dL
  • Serum bicarbonate ≥18 mEq/L
  • Venous pH ≥7.3 1

Special Considerations

Transition from IV to Subcutaneous Insulin

• For patients with resolved DKA who remain NPO:

  • Continue IV insulin and fluid replacement
  • Supplement with subcutaneous regular insulin every 4 hours as needed
  • For adults: 5-unit increments for every 50 mg/dL increase in blood glucose above 150 mg/dL (up to 20 units for blood glucose of 300 mg/dL) 1

• When patient can eat:

  • Start multiple-dose schedule using combination of short/rapid-acting and intermediate/long-acting insulin
  • Continue IV insulin infusion for 1-2 hours after starting subcutaneous regimen to ensure adequate plasma insulin levels 1

Discharge Planning

• Begin discharge planning at admission 1
• Schedule follow-up appointment with primary care provider or endocrinologist within 1 month
• For patients with medication changes or suboptimal glucose control, schedule earlier follow-up (1-2 weeks) 1
• Ensure medication reconciliation and clear communication with outpatient providers 1

Common Pitfalls to Avoid

1. Abrupt discontinuation of IV insulin without overlap with subcutaneous regimen can lead to poor glycemic control 1
2. Relying on nitroprusside method to monitor ketone levels during DKA treatment (β-OHB measurement is preferred) 1
3. Failing to identify and treat underlying causes of hyperglycemia (infection, myocardial infarction, etc.) 1
4. Inadequate fluid resuscitation in patients with significant dehydration
5. Overaggressive correction of glucose and osmolality, which may increase risk of cerebral edema 1

By following this structured approach to the workup and management of hyperglycemia in the ED, clinicians can effectively address this common presentation while minimizing complications and optimizing patient outcomes.