Diabetic Ketoacidosis (DKA)

Diabetic Ketoacidosis

What is Diabetic Ketoacidosis?

sugar and insulin syringe for diabetes

Introduction

Diabetic Ketoacidosis is a medical emergency and remains a serious cause of morbidity, principally in people with type 1 diabetes

Risk Factors for Diabetic Ketoacidosis

  1. Type 1 Diabetes
  2. Cerebral oedema in children and adolescents
  3. Hypokalaemia
  4. Acute respiratory distress syndrome
  5. Acute myocardial infarction
  6. Sepsis
  7. Pneumonia

Pathogenesis of Diabetic Ketoacidosis

  1. Cardinal Biomechanical features
    • Hyperketonemia (>3 mmol/L)
    • Ketonnuria (>2 on standard urine sticks)
    • Hyperglycaemia (blood glucose >11 mmol/L or >200mg/dL)
    • Metabolic acidosis (venous bicarboate <15mmol/L and Venous pH <7.3)
  2. Hyperglycaemia causes profound osmotic diuresis leading to dehydration and electrolyte loss, particularly Potassium and Sodium
  3. Potassium loss is exacerbated by secondary hyperaldosteronism due to reduced renal perfusion
  4. Ketosis result from insulin deficiency exacerbated by elevated catecholamines and other stress hormones
  5. Due to more unmetabolized acidic ketones, it starts accumulating in blood
  6. Metabolic acidosis forces hydrogen ions into cells, displacing potassium ions

Clinical Feature of Diabetic Ketoacidosis

Symptoms of Diabetic Ketoacidosis

  1. Polyuria, Thirst
  2. Weight loss
  3. Weakness
  4. Nausea, Vomitting
  5. Leg cramps
  6. Blurred vision
  7. Abdominal pain

Signs of Diabetic Ketoacidosis

  1. Dehydration
  2. Hypotension (Postural or Supine)
  3. Cold extremities / Peripheral cyanosis
  4. Tachycardia
  5. Air hunger (Kussmaul breathing)
  6. Smell of Acetone
  7. Hypothermia
  8. Confusion / Drowsiness / Coma

Investigations for Diabetic Ketoacidosis

  1. Venous blood: Urea, Electrolytes, Bicarbonates
  2. Urine or Blood analysis for ketones
  3. ECG
  4. Infection screen
    • Full blood count
    • Blood and Urine culture
    • C-reactive protein
    • Chest X-ray

Treatment for Diabetic Ketoacidosis

  1. Insulin
    • A fixed rate IV infusion of 0.1U/kg body weight/hr is recommended
    • If IV not possible soluble insulin can be given by intramuscular injection with loading dose of 10-20 U, followed by 5 U hourly
    • Alternatively fast acting insulin analogue can be given hourly by subcutaneous injection with initial dose of 0.3 U/kg body weight, followed by 0.1 U/kg hourly
  2. Fluid Replacement
    • Rapid fluid replacement for first few hours is recommennded for adults
    • Caution is recommended in children and adolescent due to chances of developing cerebral oedema
  3. Potassium
    • Careful monitoring of potassium is essential to prevent hyperkalaemia or hypokalaemia
    • Potassium replacement usually not recommended in initial treatment because pre-renal failure maybe present secondary to dehydration
    • Cardiac rhythm should be monitored in severe DKA due to risk of electrolyte induced cardiac arrhythmia
  4. Bicarbonate: Adequate fluid and insulin replacement should resolve acidosis