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).