From the Guidelines
Low bicarbonate levels should be treated with intravenous sodium bicarbonate only in severe cases or when the patient is symptomatic, with the dose calculated using the formula: Bicarbonate deficit (mEq) = 0.5 × weight (kg) × (24 - measured bicarbonate), and only 50% of the calculated deficit should be administered initially over 4-8 hours, with reassessment afterward, as recommended by the most recent and highest quality study 1.
Treatment Approach
The treatment of low bicarbonate levels (metabolic acidosis) depends on the underlying cause and severity of the condition.
- For mild to moderate cases, oral sodium bicarbonate supplementation may be considered.
- However, for severe cases or symptomatic patients, intravenous sodium bicarbonate may be necessary.
Calculation of Bicarbonate Deficit
The bicarbonate deficit can be calculated using the formula: Bicarbonate deficit (mEq) = 0.5 × weight (kg) × (24 - measured bicarbonate) 1.
Administration of Sodium Bicarbonate
Only 50% of the calculated deficit should be administered initially over 4-8 hours, with reassessment afterward.
Identifying and Treating the Underlying Cause
The primary focus should be on identifying and treating the underlying cause of the metabolic acidosis, which may include kidney disease, diabetic ketoacidosis, severe diarrhea, or medication effects, as addressing the root cause is essential, and bicarbonate supplementation alone is a temporary measure 1.
Monitoring for Potential Complications
Patients should be monitored for potential complications of treatment, including fluid overload, hypokalemia, and paradoxical central nervous system acidosis.
Dietary Modifications
Dietary modifications to include more fruits and vegetables and fewer acid-producing foods may help maintain bicarbonate levels long-term in chronic conditions.
Recent Guidelines
Recent guidelines suggest that the use of bicarbonate in patients with diabetic ketoacidosis made no difference in resolution of acidosis or time to discharge, and its use is generally not recommended 1.
From the FDA Drug Label
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 Treatment of metabolic acidosis should, if possible, be superimposed on measures designed to control the basic cause of the acidosis - e.g., insulin in uncomplicated diabetes, blood volume restoration in shock. Vigorous bicarbonate therapy is required in any form of metabolic acidosis where a rapid increase in plasma total CO2 content is crucial - e. g., cardiac arrest, circulatory insufficiency due to shock or severe dehydration, and in severe primary lactic acidosis or severe diabetic acidosis.
Low bicarbonate treatment involves administering sodium bicarbonate (IV) to patients with metabolic acidosis. The treatment is indicated for conditions such as:
- Severe renal disease
- Uncontrolled diabetes
- Circulatory insufficiency due to shock or severe dehydration
- Cardiac arrest
- Severe primary lactic acidosis The goal of bicarbonate therapy is to minimize risks inherent to the acidosis itself and to rapidly increase plasma total CO2 content in crucial cases 2.
From the Research
Low Bicarbonate Treatment
- The use of sodium bicarbonate to treat metabolic acidosis is intuitive, yet data suggest that not all patients benefit from this therapy 3.
- Sodium bicarbonate can be administered as a hypertonic push, as a resuscitation fluid, or as an infusion, but its empiric use in patients with nontoxicologic causes of metabolic acidosis is not warranted and likely does not improve patient-centered outcomes, except in select scenarios 3.
- Recent data suggest that the use of sodium bicarbonate in diabetic ketoacidosis does not confer improved patient outcomes and may cause harm in pediatric patients 3.
- Available evidence suggests that alkalinization of urine in rhabdomyolysis does not improve patient-centered outcomes 3.
- Patients with a nongap acidosis benefit from sodium bicarbonate supplementation 3.
- Early sodium bicarbonate is administered by clinicians to more severely ill patients but without correction for weight or acidosis severity, and its association with ICU mortality is not significant after adjusting for confounders 4.
- Bicarbonate therapy in acidotic vasopressor-dependent patients may be beneficial and warrants further investigation 4.
Metabolic Acidosis
- Metabolic acidosis is characterized by a primary reduction in serum bicarbonate concentration, a secondary decrease in the arterial partial pressure of carbon dioxide, and a reduction in blood pH 5.
- Acute forms of metabolic acidosis most frequently result from the overproduction of organic acids, while chronic metabolic acidosis often reflects bicarbonate wasting and/or impaired renal acidification 5.
- The calculation of the serum anion gap aids diagnosis by classifying the disorders into categories of normal or elevated anion gap 5.
- Adverse effects of acute metabolic acidosis include decreased cardiac output, arterial dilatation with hypotension, altered oxygen delivery, decreased ATP production, predisposition to arrhythmias, and impairment of the immune response 5.
- The main adverse effects of chronic metabolic acidosis are increased muscle degradation and abnormal bone metabolism 5.
Treatment with Sodium Bicarbonate
- Using base to treat acute metabolic acidosis is controversial due to a lack of definitive benefit and potential complications 5.
- The administration of base for the treatment of chronic metabolic acidosis is associated with improved cellular function and few complications 5.
- Sodium bicarbonate therapy in patients with CKD stages 3 and 4 significantly increases serum bicarbonate and decreases potassium levels, but no differences were found in muscle function or bone mineral density between the randomly assigned groups 6.
- Metabolic acidosis is common among patients with idiopathic intracranial hypertension treated with acetazolamide, but it is not correlated with clinical adverse effects 7.