What is the management for severe diabetic ketoacidosis (DKA)?

Management of Severe Diabetic Ketoacidosis (DKA)

The management of severe DKA requires immediate fluid resuscitation with isotonic saline at 15-20 mL/kg/hour for the first hour, followed by continuous intravenous regular insulin at 0.1 units/kg/hour until resolution of ketoacidosis, regardless of glucose levels. 1, 2

Diagnosis and Initial Assessment

• DKA is diagnosed by the triad of blood glucose >250 mg/dL, arterial pH <7.0 (severe DKA), serum bicarbonate <10 mEq/L, and positive serum/urine ketones 3
• Initial laboratory evaluation must include plasma glucose, blood urea nitrogen, creatinine, serum ketones, electrolytes with calculated anion gap, osmolality, urinalysis, arterial blood gases, complete blood count with differential, and electrocardiogram 1
• Direct measurement of β-hydroxybutyrate in blood is preferred over nitroprusside method for monitoring ketosis, as nitroprusside only measures acetoacetic acid and acetone 2
• Identify precipitating factors such as infection, myocardial infarction, stroke, medication non-adherence, or newly diagnosed diabetes 1

Fluid Therapy

• Begin with isotonic saline (0.9% NaCl) at 15-20 mL/kg/hour (approximately 1-1.5 L in average adult) during the first hour to restore circulatory volume and tissue perfusion 3, 1
• After the first hour, adjust fluid choice based on hydration status, serum electrolyte levels, and urine output:
  • If corrected serum sodium is normal or elevated: use 0.45% NaCl at 4-14 mL/kg/hour 3
  • If corrected serum sodium is low: continue 0.9% NaCl at similar rate 3
• When serum glucose reaches 250 mg/dL, change to 5% dextrose with 0.45-0.75% NaCl to prevent hypoglycemia while continuing insulin therapy 2
• Total body water deficit in severe DKA is typically 100 mL/kg; aim to correct estimated deficits within 24 hours 3, 1

Insulin Therapy

• After excluding hypokalemia (<3.3 mEq/L), administer intravenous regular insulin bolus at 0.15 U/kg followed by continuous infusion at 0.1 U/kg/hour 1, 2
• If plasma glucose does not fall by 50 mg/dL in the first hour, double the insulin infusion rate every hour until a steady glucose decline of 50-75 mg/hour is achieved 1
• Continue insulin infusion until resolution of ketoacidosis (pH >7.3, serum bicarbonate ≥18 mEq/L, and anion gap ≤12 mEq/L) regardless of glucose levels 2
• Do not interrupt insulin infusion when glucose falls below 250 mg/dL; instead, add dextrose to the IV fluids while continuing insulin to clear ketones 2

Electrolyte Management

• Monitor potassium levels closely as total body potassium is depleted despite potentially normal or elevated initial serum levels due to acidosis 1
• Once renal function is assured and serum potassium <5.5 mEq/L, add 20-30 mEq potassium (2/3 KCl and 1/3 KPO₄) per liter of infusion fluid to maintain serum potassium between 4-5 mEq/L 3, 1
• If significant hypokalemia (<3.3 mEq/L) is present initially, delay insulin treatment until potassium is restored to avoid arrhythmias, cardiac arrest, and respiratory muscle weakness 1
• Bicarbonate therapy is generally not recommended for DKA patients with pH >7.0 3, 1
• For adult patients with severe acidosis (pH <6.9), consider 100 mmol sodium bicarbonate in 400 mL sterile water at 200 mL/hour 1

Monitoring During Treatment

• Draw blood every 2-4 hours to determine serum electrolytes, glucose, blood urea nitrogen, creatinine, osmolality, and venous pH 2
• Monitor fluid input/output, vital signs, and mental status continuously 1
• Target blood glucose between 150-200 mg/dL until DKA resolution parameters are met 2
• Resolution of DKA requires: glucose <200 mg/dL, serum bicarbonate ≥18 mEq/L, venous pH >7.3, and anion gap ≤12 mEq/L 2

Transition to Subcutaneous Insulin

• When DKA is resolved and the patient can eat, transition to a multiple-dose regimen using a combination of short/rapid-acting and intermediate/long-acting insulin 1
• Administer basal insulin 2-4 hours before stopping the intravenous insulin to prevent recurrence of ketoacidosis and rebound hyperglycemia 3, 1
• For newly diagnosed patients, initiate a multidose regimen at approximately 0.5-1.0 units/kg/day 1

Common Pitfalls to Avoid

• Premature termination of insulin therapy before complete resolution of ketosis can lead to recurrence of DKA 2
• Failure to add dextrose when glucose falls below 250 mg/dL while continuing insulin therapy 2
• Inadequate monitoring and replacement of electrolytes, particularly potassium 1, 2
• Overzealous fluid administration can lead to cerebral edema, particularly in children and adolescents 1
• Interruption of insulin infusion when glucose levels normalize but ketoacidosis persists 2