Diabetic Ketoacidosis

• Diabetic ketoacidosis (DKA) is a serious and potentially life-threatening complication of diabetes mellitus, characterized by hyperglycemia, ketosis, and metabolic acidosis. It is more common in patients with type 1 diabetes but can also occur in those with type 2 diabetes. DKA results from an absolute or relative deficiency of insulin, leading to increased hepatic glucose production, decreased peripheral glucose utilization, and enhanced lipolysis with subsequent ketone body formation.
• DKA risk factors:

  • Insulin deficiency
  • Acute infection
  • New onset diabetes
  • Drugs - glucocorticoids, SGLT2 inhibitors, thiazide diuretics and atypical antipsychotics
• DKA pathophysiology:

  1. Insulin deficiency, leading to reduced glucose uptake and hepatic gluconeogenesis and glycogenolysis. This all results in hyperglycemia
  2. Hyperglycemia leads to osmotic diuresis which contributes to hypovolemia, hypotension and renal impairment
  3. In response to low glucose utility, lipolysis occurs in adipose tissue, creating free fatty acids. Free fatty acids undergo ketogenesis to turn into ketones
  4. High concentration of ketones decreases the pH of the blood (acidosis) and causes more diuresis, worsening dehydration.
• Clinical features of DKA:

  • Hyperglycemia - blurred vision, headache, lethargy
  • Metabolic acidosis - Kussmaul respiration
  • Ketosis - sweet, fruity odour on breath
  • Dehydration - dry mucous membranes, tachycardia, hypotension, hypokalemia
  • Neurological - Altered mental status or seizures depending on severity
  • Abdominal - Pain, nausea, vomiting
• Lab tests for DKA:

  • Blood glucose >11.1mmol/L
  • Ketones - blood and urine
  • VBG
  • U&E
  • Hba1c
  • Infection screen
• DKA treatment:

  • Fluid replacement using isotonic saline
  • Insulin (0.1 units/kg/hr) til blood glucose is under 14mmol/L - after which 10% dextrose infusion (125mls/hr) is given alongside fluids
  • Correct electrolyte disturbance
  • Long-acting insulin should be continued, short-acting insulin should be stopped
• DKA resolution:

  • pH > 7.3
  • Blood ketones <0.6
  • Bicarbonate >15
  • Ketonemia and acidosis should resolve within 24 hours - if not then escalate to endocrinologist
• DKA complications:

  • Gastric stasis
  • Thromboembolism
  • Arrhythmia - secondary to hyperkalemia or iatrogenic hypokalemia
  • Iatrogenic - cerebral oedema, hypokalemia, hypoglycemia
  • ARDS
  • AKI