Bicarbonate Therapy in High Anion Gap Metabolic Acidosis
Indications and Administration
- The American Diabetes Association recommends bicarbonate therapy for high anion gap metabolic acidosis when arterial pH is ≤7.0, and should be administered as 100 mmol sodium bicarbonate diluted in 400 ml sterile water given at a rate of 200 ml/h 1
- For arterial pH <7.0, administer 100 mmol sodium bicarbonate added to 400 ml sterile water at a rate of 200 ml/h 1, 2
- For arterial pH 6.9-7.0, administer 50 mmol sodium bicarbonate diluted in 200 ml sterile water at a rate of 200 ml/h 1, 2
- For diabetic ketoacidosis (DKA) with pH <6.9, bicarbonate therapy may be beneficial to temporarily stabilize hemodynamics 5, 1
- The American Academy of Pediatrics recommends bicarbonate administration for sodium channel blocker overdose (e.g., tricyclic antidepressants) to maintain serum pH of 7.45-7.55 7
Special Considerations
- For toxic ingestions (methanol, ethylene glycol, salicylates), bicarbonate may be beneficial regardless of pH to enhance elimination of certain toxins 3, 6
- For pediatric patients with pH <7.0 after initial hydration, administer 1-2 mEq/kg sodium bicarbonate over 1 hour 4, 8