What is the treatment for metabolic acidosis?

From the Guidelines

The treatment for metabolic acidosis should focus on addressing the underlying cause while correcting the acid-base imbalance, with the most recent and highest quality study suggesting that the use of bicarbonate is generally not recommended for patients with diabetic ketoacidosis (DKA) 1.

Key Considerations

• The management goals for metabolic acidosis include restoration of circulatory volume and tissue perfusion, resolution of hyperglycemia, and correction of electrolyte imbalance and acidosis.
• In critically ill and mentally obtunded individuals with DKA or hyperosmolar hyperglycemic state, continuous intravenous insulin is the standard of care, as stated in the 2024 standards of care in diabetes 1.
• Successful transition from intravenous to subcutaneous insulin requires administration of basal insulin 2–4 h before the intravenous insulin is stopped to prevent recurrence of ketoacidosis and rebound hyperglycemia.
• There is no significant difference in outcomes for intravenous human regular insulin versus subcutaneous rapid-acting analogs when combined with aggressive fluid management for treating mild or moderate DKA 1.

Treatment Approaches

• For mild to moderate cases of metabolic acidosis, treatment may involve fluid resuscitation and electrolyte correction, particularly potassium, which shifts as pH normalizes.
• In severe cases (pH < 7.2), more aggressive treatment may be needed, often involving continuous infusion of bicarbonate, although its use is generally not recommended for patients with DKA 1.
• Specific treatments depend on the etiology: diabetic ketoacidosis requires insulin therapy and fluid resuscitation; lactic acidosis necessitates improving tissue perfusion and treating the underlying condition; renal tubular acidosis may require chronic oral bicarbonate supplementation; and toxic ingestions might require specific antidotes or hemodialysis.

Supportive Care

• Supportive care includes fluid resuscitation, electrolyte correction, and respiratory support if needed.
• Treatment aims to restore normal acid-base balance by eliminating excess acid production, enhancing acid excretion, or providing base supplementation, as metabolic acidosis can impair cardiac function, decrease response to vasopressors, and cause respiratory distress if left untreated.
• The use of bicarbonate in patients with DKA made no difference in the resolution of acidosis or time to discharge, and its use is generally not recommended, as stated in the 2023 standards of care in diabetes 1.

From the FDA Drug Label

In cardiac arrest, a rapid intravenous dose of one to two 50 mL vials (44.6 to 100 mEq) may be given initially and continued at a rate of 50 mL (44. 6 to 50 mEq) every 5 to 10 minutes if necessary (as indicated by arterial pH and blood gas monitoring) to reverse the acidosis. In less urgent forms of metabolic acidosis, Sodium Bicarbonate Injection, USP may be added to other intravenous fluids The amount of bicarbonate to be given to older children and adults over a four-to-eight-hour period is approximately 2 to 5 mEq/kg of body weight - depending upon the severity of the acidosis as judged by the lowering of total CO2 content, blood pH and clinical condition of the patient Sodium Bicarbonate Injection, USP is indicated in the treatment of metabolic acidosis which may occur in severe renal disease, uncontrolled diabetes, circulatory insufficiency due to shock or severe dehydration, extracorporeal circulation of blood, cardiac arrest and severe primary lactic acidosis

The treatment for metabolic acidosis is sodium bicarbonate (IV). The dosage and administration vary depending on the severity of the acidosis and the patient's condition.

• In cardiac arrest, a rapid intravenous dose of 44.6 to 100 mEq may be given initially, followed by 50 mL (44.6 to 50 mEq) every 5 to 10 minutes if necessary.
• In less urgent forms, 2 to 5 mEq/kg of body weight may be given over a four-to-eight-hour period. Treatment should be planned in a stepwise fashion, with monitoring of blood gases, plasma osmolarity, arterial blood lactate, hemodynamics, and cardiac rhythm 2. The goal is to minimize risks inherent to the acidosis itself, while also addressing the underlying cause of the acidosis 2.

From the Research

Treatment of Metabolic Acidosis

The treatment of metabolic acidosis involves addressing the underlying cause of the condition and providing supportive care. Some key aspects of treatment include:

• Restoration of circulating volume and electrolyte replacement 3
• Correction of insulin deficiency to resolve metabolic acidosis and ketosis in cases of diabetic ketoacidosis 3
• Use of sodium bicarbonate infusion in certain cases, although its effectiveness is still a topic of debate 4, 5
• Administration of tris(hydroxymethyl)aminomethane (THAM) as a potential alternative to sodium bicarbonate 5
• Selective sodium-hydrogen exchanger 1 (NHE1) inhibitors as a potential novel treatment approach 5

Diagnostic Approach

A systematic approach to diagnosing metabolic acidosis is crucial for proper management. This includes:

• Calculation of the anion and osmolal gaps to narrow down diagnostic possibilities 4
• Assessment of acid-base parameters, including pH, partial pressure of CO(2), and HCO(3)(-) concentration in arterial blood 5
• Evaluation of the patient's clinical history, physical examination, and other hematological values 4, 6

Management Guidelines

Various guidelines have been developed for the management of metabolic acidosis, including those from the French Intensive Care Society and the French Emergency Medicine Society 7. These guidelines address diagnostic strategy, patient assessment, and therapeutic management, and provide recommendations for the use of insulin therapy, sodium bicarbonate infusion, and other treatments.