What is the treatment for metabolic acidosis?

Treatment of Metabolic Acidosis

Treatment of metabolic acidosis must be tailored to the underlying etiology, with the primary focus on correcting the root cause rather than simply administering bicarbonate, which has limited evidence for improving mortality or morbidity in most acute settings. 1, 2

Etiology-Specific Treatment Approach

Diabetic Ketoacidosis (DKA)

• Insulin therapy, fluid resuscitation, and electrolyte replacement are the cornerstones of DKA treatment, not bicarbonate administration. 2
• Continuous intravenous insulin is the standard of care for critically ill and mentally obtunded patients with DKA. 2
• Restoration of circulatory volume and tissue perfusion is a primary goal. 2
• Bicarbonate administration has not been shown to improve resolution of acidosis or time to discharge in DKA. 1, 2

Lactic Acidosis and Tissue Hypoperfusion

• Avoid using sodium bicarbonate to treat metabolic acidosis arising from tissue hypoperfusion without careful consideration, as it may worsen intracellular acidosis. 1
• The only effective treatment for organic acidosis is cessation of acid production via improvement of tissue oxygenation. 3
• Bicarbonate administration may worsen intracellular acidosis, reduce ionized calcium, and produce hyperosmolality. 1, 2

Chronic Kidney Disease (CKD)-Associated Acidosis

• Treat CKD-associated acidosis when serum bicarbonate is consistently < 18 mmol/L to prevent bone and muscle metabolism abnormalities. 1, 2
• Oral sodium bicarbonate (2-4 g/day or 25-50 mEq/day) can effectively increase serum bicarbonate concentrations. 2
• Maintain serum bicarbonate at or above 22 mmol/L in maintenance dialysis patients. 2
• Correction of acidemia has been associated with increased serum albumin, decreased protein degradation rates, and increased plasma concentrations of branched chain amino acids. 2
• Avoid citrate alkali salts in CKD patients exposed to aluminum salts as they may increase aluminum absorption. 2

Renal Tubular Acidosis in Children

• Normalization of serum bicarbonate is important for normal growth parameters. 2

Indications for Sodium Bicarbonate Therapy

FDA-Approved Indications

Sodium bicarbonate injection is indicated for: 4

• Severe renal disease
• Uncontrolled diabetes
• Circulatory insufficiency due to shock or severe dehydration
• Cardiac arrest
• Severe primary lactic acidosis
• Drug intoxications (barbiturates, salicylates, methyl alcohol)
• Hemolytic reactions requiring alkalinization of urine
• Severe diarrhea with significant bicarbonate loss

When Vigorous Bicarbonate Therapy is Required

Vigorous bicarbonate therapy is indicated when rapid increase in plasma total CO2 content is crucial: 4

• Cardiac arrest
• Circulatory insufficiency due to shock or severe dehydration
• Severe primary lactic acidosis
• Severe diabetic acidosis

Critical Monitoring Parameters

Electrolyte Monitoring

• Monitor potassium levels closely, as acidosis causes hyperkalemia due to transcellular shift of potassium. 1, 2
• Monitor serum bicarbonate levels monthly in maintenance dialysis patients. 2

Complications of Bicarbonate Administration

• May worsen intracellular acidosis 1, 2
• Can reduce ionized calcium 1, 2
• May produce hyperosmolality 1, 2

Common Pitfalls to Avoid

• Do not use potassium chloride alone to treat hypokalemia in patients with metabolic acidosis; use an alkalinizing potassium salt such as potassium bicarbonate, potassium citrate, potassium acetate, or potassium gluconate instead. 5
• Do not rely solely on bicarbonate therapy without addressing the underlying cause of acidosis. 4, 3
• Do not administer bicarbonate routinely in DKA, as it has not demonstrated clinical benefit. 1, 2