Definition: Diabetic ketoacidosis (DKA) is a life-threatening complication of diabetes mellitus, characterized by hyperglycemia, ketonemia, and metabolic acidosis due to absolute or relative insulin deficiency.

• Pathophysiology:
  • Insulin deficiency → increased lipolysis → elevated free fatty acids → ketogenesis (acetoacetate, β-hydroxybutyrate).
  • Hyperglycemia → osmotic diuresis → dehydration, electrolyte loss (Na⁺, K⁺, Cl⁻).
  • Metabolic acidosis (pH < 7.3, HCO₃⁻ < 18 mmol/L) due to ketoacid accumulation.
• Precipitating Factors:
  • Type 1 diabetes: insulin omission, infection, myocardial infarction.
  • Type 2 diabetes: severe illness, new-onset diabetes, SGLT2 inhibitors.
• Diagnostic Criteria (ADA 2026):
  • Hyperglycemia: BG > 250 mg/dL (13.9 mmol/L).
  • Ketonemia: β-hydroxybutyrate > 3 mmol/L or ketonuria ++.
  • Acidosis: pH < 7.3, HCO₃⁻ < 18 mmol/L.
• Management (ADA 2026):
  • Fluid resuscitation: 0.9% NaCl, 1–1.5 L in first hour (if no shock, 500 mL/h).
  • Insulin therapy: IV regular insulin, 0.1 U/kg/h (after initial bolus if severe).
  • Electrolyte correction: K⁺ supplementation (if K⁺ < 5.5 mmol/L) to prevent hypokalemia.
  • Monitoring: BG, electrolytes, pH, anion gap, mental status.
• Discharge Criteria (ADA 2026):
  • BG < 250 mg/dL, pH > 7.3, HCO₃⁻ > 18 mmol/L, stable for 24 h.
• Prevention: Patient education, SMBG, insulin adherence, sick-day rules.

Rationale: ADA 2026 guidelines emphasize prompt fluid/insulin correction to reverse acidosis and prevent complications (e.g., cerebral edema, hypokalemia).