Introduction
Diabetic ketoacidosis (DKA) is a severe acute illness that is characterized by hyperglycemia, ketonaemia and metabolic acidosis. It can be precipitated by illness, gastroenteritis and missing doses of insulin.
All children presenting with a glucose level >11.1mmol/L should have a capillary blood ketone checked, because DKA may be the first presentation of diabetes in children.
- Venous pH <7.3
- Venous bicarbonate <18 mmol/L
- Venous or capillary ketones >3.0mmol/L
If ketones are negative or if pH is normal, but ketones are elevated, treat with subcutaneous insulin
DKA develops in the presence of three triggers which combine:
- A major stress or acute illness
- This leads to a surge in catecholamines & glucagon
- These hormones cause:
- Insulin resistance and hyperglycemia
- Ketoacidosis
- Hyperglycemia and dehydration
- Polyuria leads to dehydration and electrolyte disturbance
- Severe dehydration leads to insulin resistance and worsening hyperglycemia
- Carbohydrate and insulin deficiency
- Vomiting and starvation will trigger ketosis
- Missing doses of insulin leads to ketoacidosis
Treatment needs to address all of these triggers:
- Treat the stress or remove the trigger
- Rehydration
- Give insulin and glucose to switch off the ketosis
Diagnostic criteria
The diagnosis of DKA is made on the results of venous blood:
- pH <7.30
- Bicarbonate <18 mmol/L
- Glucose >13 mmol/L
Confirmatory results:
- Capillary ketones >3.0mmol/L
- Osmolality <250 mOsm/kg
- Moderate dehydration
Severity of the DKA is defined by the venous pH:
- Mild DKA: pH 7.25 – 7.30
- Moderate DKA: pH 7.0 – 7.24
- Severe DKA: pH <7.0
Alternative diagnoses
Ketosis (normal pH, elevated ketones)
Elevated ketones but a normal pH indicates ketosis. This can be treated with fluids, IV or oral glucose and insulin. It may be due to:
- Weight loss
- Dehydration
- Ketogenic (very low carbohydrate) diet
- Excess alcohol
- Pregnancy and lactation
HHS (Hyperosmolar Hyperglycaemic State)
Clinical presentation
Symptoms of DKA:
- Fatigue
- Nausea and vomiting
- Dyspnoea
- Abdominal pain
- Thirst & polyuria
- Altered level of consciousness
- Low grade fever
Examination findings:
- Agitation or altered level of consciousness
- Tachypnoea
- Fruity breath (ketones)
- Tachycardia
- Dehydration
- Mild (<4%) – no clinical signs
- Moderate (4-7%) – poor capillary return, reduced skin turgor, tachycardia
- Severe (>7%) – poor perfusion, hypotension
- Signs of sepsis if this is underlying trigger for DKA
Exclude other causes of ketoacidosis (low pH, elevated ketones):
- Starvation
- Alcohol excess
- SGLT-2 inhibitors
Consider causes of ketosis (normal pH, elevated ketones):
Acute management of Diabetic ketoacidosis (DKA)