What is the role of sodium bicarbonate (NaHCO3) in Advanced Cardiovascular Life Support (ACLS) during cardiac arrest?

From the Guidelines

Sodium bicarbonate should not be routinely used in Advanced Cardiovascular Life Support (ACLS) during cardiac arrest, except in specific situations such as known pre-existing metabolic acidosis, hyperkalemia, or tricyclic antidepressant overdose. The use of sodium bicarbonate in cardiac arrest is based on the 2010 American Heart Association guidelines for cardiopulmonary resuscitation and emergency cardiovascular care 1. According to these guidelines, there is no evidence that bicarbonate improves the likelihood of defibrillation or survival rates in animals with VF cardiac arrest. In fact, bicarbonate may compromise coronary perfusion pressure, create extracellular alkalosis, produce hypernatremia and hyperosmolarity, and exacerbate central venous acidosis.

Key Points to Consider

• The routine use of sodium bicarbonate is not recommended for patients in cardiac arrest (Class III, LOE B) 1
• Sodium bicarbonate may be beneficial in special resuscitation situations, such as preexisting metabolic acidosis, hyperkalemia, or tricyclic antidepressant overdose 1
• When used, the typical adult dose is 1 mEq/kg for the initial dose, with subsequent doses guided by arterial blood gas results 1
• The current emphasis in cardiac arrest management is on high-quality chest compressions, early defibrillation when indicated, and addressing underlying causes rather than routine administration of sodium bicarbonate 1

Risks and Benefits

• Risks of sodium bicarbonate use include paradoxical intracellular acidosis, hypernatremia, hyperosmolarity, and decreased coronary perfusion pressure 1
• Benefits of sodium bicarbonate use may include buffering excess hydrogen ions and potentially raising blood pH in specific situations 1

Clinical Decision Making

• Clinicians should exercise caution when considering the use of sodium bicarbonate in cardiac arrest, weighing the potential benefits against the significant risks 1
• High-quality chest compressions, early defibrillation, and addressing underlying causes should remain the primary focus of cardiac arrest management 1

From the FDA Drug Label

In cardiac arrest, a rapid intravenous dose of one to two 50 mL syringes (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. 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 role of sodium bicarbonate (NaHCO3) in Advanced Cardiovascular Life Support (ACLS) during cardiac arrest is to reverse metabolic acidosis. The recommended dose is 1 to 2 ampules (44.6 to 100 mEq) initially, followed by 50 mL (44.6 to 50 mEq) every 5 to 10 minutes as needed, based on arterial pH and blood gas monitoring 2. Sodium bicarbonate is indicated for the treatment of metabolic acidosis in cardiac arrest 2.

• Key points:
  • Dose: 1 to 2 ampules (44.6 to 100 mEq) initially
  • Administration: 50 mL (44.6 to 50 mEq) every 5 to 10 minutes as needed
  • Monitoring: arterial pH and blood gas monitoring
  • Indication: treatment of metabolic acidosis in cardiac arrest 2, 2

From the Research

Role of Sodium Bicarbonate in ACLS during Cardiac Arrest

• The use of sodium bicarbonate (NaHCO3) in Advanced Cardiovascular Life Support (ACLS) during cardiac arrest is a topic of ongoing debate 3, 4, 5, 6, 7.
• A systematic literature review published in 2024 found that despite some studies suggesting potential benefits of sodium bicarbonate in prolonged CPR, the overall data revealed lower rates of return of spontaneous circulation (ROSC) and poor outcomes associated with its use 3.
• A cross-sectional survey study of adult and pediatric clinicians found that approximately 50% of physicians reported using sodium bicarbonate during in-hospital cardiac arrest, with the most common indications being hyperkalemia, metabolic acidosis, tricyclic antidepressant overdose, and prolonged arrest duration 4.
• A double-blind, randomized, placebo-controlled pilot study published in 2018 found that sodium bicarbonate improved acid-base status in patients with severe metabolic acidosis during prolonged CPR, but did not improve the rate of ROSC or good neurologic survival 5.
• Earlier studies published in 1998 and 1996 evaluated the evidence supporting the use of sodium bicarbonate in cardiac arrest and found that its use is not universally recommended, with potential benefits and harms depending on the specific clinical context 6, 7.

Indications for Sodium Bicarbonate Use

• Hyperkalemic cardiac arrest 3, 4
• Severe cardiotoxicity 3
• Overdose due to tricyclic antidepressants 3
• Prolonged arrest duration 4
• Severe metabolic acidosis during prolonged CPR 5

Limitations and Future Directions

• The current evidence base is limited, and further studies are needed to determine the potential benefits and harms of sodium bicarbonate use in cardiac arrest 3, 4, 5.
• A larger trial is needed to verify the efficacy of sodium bicarbonate in improving outcomes in cardiac arrest patients 5.