Diabetic Ketoacidosis (DKA) in Children and Adolescents

Background

• Diabetic ketoacidosis (DKA) is a common metabolic emergency occurring in patients with diabetes.
  • It is characterized by hyperglycemia and acidosis.
  • It is caused by insulin deficiency, generally due to:
    • insulin noncompliance or mismanagement in patients with known diabetes
    • delayed diagnosis of new-onset diabetes
• The goal of prompt recognition and treatment is to prevent complications, especially cerebral edema, which is associated with 20%-25% mortality.

Evaluation

• Common findings at presentation:
  • polydipsia, polyuria, nausea, vomiting, weakness, and lethargy developing over about 24 hours
  • dehydration, Kussmaul respirations (deep respirations), fruity odor on breath, and mental status changes
• Initial testing should include:
  • serum glucose, electrolytes, ketones, and blood gas
  • urine dipstick and urinalysis
  • electrocardiogram
  • complete blood count with differential
  • renal and liver function tests
• Diagnostic findings for diabetic ketoacidosis (DKA) are:
  • serum glucose > 200 mg/dL (11 mmol/L)
  • blood pH level < 7.3 or serum bicarbonate level < 18 mEq/L (18 mmol/L)
  • presence of serum or urine ketones

Relevant Calculators

• Anion Gap Calculator
• Osmolar Gap Calculator
• Osmolality Estimator (serum)
• Sodium Correction in Hyperglycemia

Management

• Fluids and electrolytes
  • Begin fluid resuscitation with 0.9% saline or Ringer lactate 10-20 mL/kg IV over 20-30 minutes (repeat bolus as needed for shock).
  • After the initial bolus, estimate the degree of dehydration and aim to replace the fluid deficit over 24-48 hours.
    • Avoid infusion rates > 1.5-2 times the maintenance requirement because excessive fluid may increase the risk of cerebral edema.
    • Use 0.45%-0.9% saline or Ringer lactate IV for the first 4-6 hours, then use ≥ 0.45% saline.
  • Add potassium to the IV fluid (if hyperkalemic, defer until urine output established).
  • Consider magnesium supplementation if magnesium < 1.2 mg/dL (0.5 mmol/L, 1 mEq/L).
  • Consider potassium repletion in the form of potassium phosphate if phosphorus < 1 mg/dL (0.32 mmol/L).
• Insulin and Dextrose
  • Begin insulin therapy after 1 hour of fluid bolus.
    • Administer 0.1 units/kg/hour IV as continuous infusion until diabetic ketoacidosis (DKA) resolves: pH > 7.3, bicarbonate > 18 mEq/L (18 mmol/L), or anion gap < 12 mEq/L (12 mmol/L).
    • Alternatively, 0.05 units/kg/hour dose may be used in milder cases, and in young children with significant sensitivity to insulin as long as metabolic acidosis is resolving.
  • Add 5%-12.5% glucose to the IV fluid when plasma glucose decreases to 250-300 mg/dL (14-17 mmol/L).
  • Consider adding 2.5% or 5% glucose to the rehydration fluid if plasma glucose is decreasing > 100 mg/dL/hour (5.5 mmol/L/hour).
  • Transition to subcutaneous insulin when acidosis has resolved, blood glucose is < 200 mg/dL (11.1 mmol/L), and patient is tolerating oral fluids.