What is the initial management of Diabetic Ketoacidosis (DKA)?

Initial Management of Diabetic Ketoacidosis (DKA)

The initial management of DKA requires immediate fluid resuscitation with isotonic saline (0.9% NaCl) at 15-20 ml/kg/hour during the first hour, followed by insulin therapy and electrolyte replacement. 1

Diagnostic Criteria

DKA is characterized by:

• Blood glucose >250 mg/dl 1
• Arterial pH <7.3 1
• Serum bicarbonate <15 mEq/l 1
• Moderate ketonuria or ketonemia 1

Initial Assessment

• Obtain arterial blood gases, complete blood count with differential, urinalysis, blood glucose, blood urea nitrogen, electrolytes, chemistry profile, and creatinine levels 1
• Obtain chest X-ray and cultures as needed if infection is suspected 1
• Calculate corrected serum sodium (for each 100 mg/dl glucose >100 mg/dl, add 1.6 mEq to sodium value) 1

Treatment Algorithm

1. Fluid Therapy

• Begin with isotonic saline (0.9% NaCl) at 15-20 ml/kg/hour during the first hour (1-1.5 liters in average adult) 1
• After initial resuscitation, adjust fluid choice based on:
  • If corrected serum sodium is normal or elevated: use 0.45% NaCl at 4-14 ml/kg/hour 1
  • If corrected serum sodium is low: continue 0.9% NaCl at similar rate 1
• Recent evidence suggests balanced electrolyte solutions may result in faster DKA resolution than 0.9% saline (median 13.0 vs 16.9 hours) 2, 3

2. Insulin Therapy

• Once hypokalemia is excluded, administer intravenous regular insulin:
  • Initial bolus: 0.1 units/kg body weight 1
  • Continuous infusion: 0.1 units/kg/hour 1
• If plasma glucose does not fall by 50 mg/dl in first hour, double insulin infusion hourly until steady glucose decline of 50-75 mg/hour is achieved 1
• For mild DKA only: Consider subcutaneous/intramuscular insulin regimen with priming dose of 0.4-0.6 units/kg (half IV bolus, half SC/IM) followed by 0.1 unit regular insulin SC/IM hourly 1

3. Electrolyte Management

• Once renal function is assured, add 20-30 mEq/L potassium (2/3 KCl and 1/3 KPO4) to IV fluids 1
• Begin potassium replacement when serum levels fall below 5.5 mEq/L 4
• Monitor potassium closely as total body deficits are common despite potentially normal initial levels due to acidosis 4
• Phosphate replacement may be considered in patients with cardiac dysfunction, anemia, respiratory depression, or serum phosphate <1.0 mg/dL 1
• Bicarbonate therapy:
  • Generally not recommended if pH >7.0 1
  • May be beneficial if pH <6.9 1

4. Monitoring

• Check blood glucose hourly 1
• Monitor electrolytes, venous pH, and anion gap every 2-4 hours 1
• Direct measurement of β-hydroxybutyrate (β-OHB) in blood is preferred over nitroprusside method for monitoring ketosis resolution 1

Resolution Criteria and Transition of Care

• DKA resolution defined as: glucose <200 mg/dl, serum bicarbonate ≥18 mEq/l, and venous pH ≥7.3 1
• Once DKA resolves:
  • If patient is NPO: Continue IV insulin and fluids, supplement with subcutaneous regular insulin as needed every 4 hours 1
  • When patient can eat: Transition to multiple-dose insulin regimen with combination of short/rapid-acting and intermediate/long-acting insulin 1
  • Continue IV insulin for 1-2 hours after starting subcutaneous regimen to ensure adequate plasma insulin levels 1

Common Pitfalls and Caveats

• Avoid abrupt discontinuation of IV insulin when transitioning to subcutaneous insulin to prevent rebound hyperglycemia 1
• Do not rely on nitroprusside method (urine ketones) to monitor treatment response, as β-OHB converts to acetoacetate during treatment, potentially giving false impression of worsening ketosis 1
• Cerebral edema is a rare but serious complication, especially in pediatric patients - avoid too rapid correction of glucose and osmolality 1
• Identify and treat precipitating factors (infection, myocardial infarction, trauma, drugs, etc.) 1, 5
• DKA must be distinguished from other causes of high-anion gap metabolic acidosis including lactic acidosis, salicylate/methanol/ethylene glycol ingestion, and chronic renal failure 1