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, alcohol or illicit drugs and missing doses of insulin.
It typically develops in people with Type 1 Diabetes but can also occur in people with Type 2 Diabetes. SGLT-2 inhibitors eg. Empagliflozin, Dapagliflozin can cause euglycemic DKA as a side effect.
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)