Chapter 59: Diabetic Ketoacidosis

DEFINITION AND DIAGNOSIS

Diabetic ketoacidosis (DKA) mainly affects children with type 1 diabetes mellitus (T1DM) and is caused by a deficiency in circulating insulin levels and elevations in other hormones like glucagon and cortisol. This, in turn, leads to:

• Impaired glucose consumption by the peripheral tissues with elevations in plasma glucose levels

• Increased glucose production by the liver through gluconeogenesis and glycogenolysis

• Increased serum osmolality

• Increased lipolysis with production of ketone bodies (ß-hydroxybutyrate) and resultant ketonemia

• Profound anion gap metabolic acidosis

The hyperglycemia and acidosis associated with DKA result in a profound osmotic diuresis, significant dehydration, glycosuria, ketonuria, ketonemia, and electrolyte disturbances.

SIGNS AND SYMPTOMS OF ACUTE DKA CAN INCLUDE:

• Polyuria/increased urination

• Polydipsia/increased thirst

• Vomiting and dehydration

• Abdominal pain

• Irregular respirations (Kussmaul breathing: large, deep, gasping breaths)

• Weakness and lethargy

• Altered mental status and confusion

• Loss of consciousness or coma

THE DIAGNOSTIC CRITERIA FOR DKA INCLUDE:

• Hyperglycemia (serum glucose >250–300 mg/dL)

• Significant venous acidosis (pH <7.3)

• Serum bicarbonate levels ≤15 mmol/L

DKA IS GENERALLY CATEGORIZED ACCORDING TO THESE pH AND BICARBONATE VALUES (Table 59-1).

INCIDENCE OF DKA

• As mentioned, DKA occurs more commonly in patients with T1DM but has been seen in older children with type 2 diabetes mellitus. DKA at the onset of T1DM occurs more frequently in:

  • Young children (age <4 years)

  • Children of lower socioeconomic status

  • Children without a significant family history of diabetes

• Children with known relatives with T1DM are more frequently evaluated by clinicians and are less likely to present in DKA.

• Children with known T1DM have a 1% to 10% risk of having an episode of DKA/year

• Children at higher risk for DKA after the diagnosis of T1DM are:

  • Peripubertal/adolescent girls

  • Children from lower-income households

  • Children with mood or eating disorders

  • Children with poor self or parental compliance to medical therapy

• DKA can often be precipitated by:

  • An intercurrent illness (e.g., viral or bacterial infection)

  • Inadequate insulin administration

  • Corticosteroid or diuretic use

  • Exacerbation of another underlying disease that puts the body under a stress state (e.g., pancreatitis, trauma, heart disease)

MANAGING DKA

In known T1DM patients with evidence of urinary ketones or elevated glucose without significant acidosis, care can be managed at home in close contact with a pediatric endocrinologist.

Children with new-onset T1DM or moderate to severe DKA should be considered for inpatient or pediatric intensive care admission.

INITIAL STABILIZATION OF PATIENTS IN DKA IN AN ACUTE CARE SETTING SHOULD INCLUDE: