Sodium Bicarbonate Ampule Dosing Guidelines
The recommended dose for administering sodium bicarbonate from an ampule is 1-2 mEq/kg given slowly intravenously for treating metabolic acidosis. 1, 2
Standard Dosing for Metabolic Acidosis
- For adults with severe metabolic acidosis (pH < 7.1), administer 1-2 mEq/kg IV given slowly 1, 2
- For children, the standard dose is also 1-2 mEq/kg IV given slowly 3, 2
- In cardiac arrest situations, a more rapid administration may be required - 1-2 vials (44.6-100 mEq) initially, followed by 50 mL (44.6-50 mEq) every 5-10 minutes if necessary 1
- For newborn infants, only use the 0.5 mEq/mL concentration, with dilution of available stock solutions as necessary 3, 2
Specific Clinical Scenarios
- For ventricular arrhythmia associated with cocaine toxicity, administer 1-2 mEq/kg sodium bicarbonate 3
- For sodium channel blocker toxicity (e.g., tricyclic antidepressant overdose), administer 1-2 mEq/kg as an initial bolus 4, 2
- For hyperkalemia, 1-2 mEq/kg is recommended to help shift potassium into cells 2
Administration Guidelines
- Ensure effective ventilation is established before administering bicarbonate, as ventilation is needed to eliminate excess CO2 produced 2, 5
- Do not mix sodium bicarbonate with vasoactive amines or calcium 3
- For less urgent forms of metabolic acidosis, sodium bicarbonate may be added to other intravenous fluids 1
- In metabolic acidosis associated with shock, therapy should be monitored by measuring blood gases, plasma osmolarity, arterial blood lactate, hemodynamics, and cardiac rhythm 1
Monitoring During Treatment
- Monitor serum bicarbonate every 2-4 hours during active bicarbonate infusion therapy 5
- Follow venous pH and anion gap to monitor resolution of acidosis 5
- Continue sodium bicarbonate infusion until serum bicarbonate reaches ≥22 mmol/L or pH rises above 7.0 5
- Avoid extremes of hypernatremia (serum sodium not to exceed 150-155 mEq/L) and alkalemia (serum pH not to exceed 7.50-7.55) 2
Potential Adverse Effects
- Sodium bicarbonate can cause extracellular alkalosis, shifting the oxyhemoglobin curve and inhibiting oxygen release 2
- It can lead to hypernatremia, hyperosmolarity, and excess CO2 production causing paradoxical intracellular acidosis 2, 4
- Bicarbonate can inactivate simultaneously administered catecholamines 2
- Excessive doses (>6 mmol/kg) may cause hypernatremia, fluid overload, metabolic alkalosis, and cerebral edema 4
- Common side effects include electrolyte abnormalities such as hypokalemia and hypocalcemia 4
Important Cautions
- It is generally unwise to attempt full correction of a low total CO2 content during the first 24 hours of therapy, as this may be accompanied by unrecognized alkalosis 1
- The achievement of total CO2 content of about 20 mEq/liter at the end of the first day of therapy will usually be associated with a normal blood pH 1
- Routine use of sodium bicarbonate in cardiac arrest is not recommended by the American College of Cardiology 2
- Routine use is not supported for sepsis-related acidosis, particularly when arterial pH is >7.15 2, 5