Sodium Bicarbonate Ampoule Concentrations
Standard sodium bicarbonate ampoules contain 1 mEq/mL (8.4% solution, 84 mg/mL), with 50 mEq in a 50 mL vial being the most common formulation used in emergency and critical care settings. 1
Available Concentrations
The FDA-approved formulations of sodium bicarbonate injection include: 1
8.4% solution: 84 mg/mL = 1 mEq/mL of both Na+ and HCO3- (osmolality 2 mOsmol/mL)
- Available in 50 mL vials (50 mEq total) or 10 mL vials (10 mEq total) 1
7.5% solution: 75 mg/mL = 0.9 mEq/mL of both Na+ and HCO3- (osmolality 1.79 mOsmol/mL)
- Available in 50 mL vials (44.6 mEq total) 1
4.2% solution: 42 mg/mL = 0.5 mEq/mL of both Na+ and HCO3- (osmolality 1 mOsmol/mL)
- Available in 10 mL vials (5 mEq total) 1
Clinical Dosing Context
Adult Emergency Dosing
The American Heart Association recommends an initial bolus of 1-2 mEq/kg (typically 50-100 mEq or 50-100 mL of 8.4% solution) for severe metabolic acidosis with pH <7.1 or life-threatening sodium channel blocker toxicity. 2, 3
Pediatric Dosing Considerations
- Children ≥2 years: 1-2 mEq/kg using 8.4% solution (1 mEq/mL), though dilution is often performed for safety 3, 4
- Children <2 years: Must dilute 8.4% solution 1:1 with normal saline to achieve 4.2% concentration (0.5 mEq/mL) 3
- Newborn infants: Only use 0.5 mEq/mL concentration (4.2% solution) 3, 4
Continuous Infusion Preparation
For ongoing alkalinization (e.g., sodium channel blocker toxicity), prepare a 150 mEq/L solution by adding 150 mEq of sodium bicarbonate to 1 liter of appropriate diluent, then infuse at 1-3 mL/kg/hour. 2, 3
Important Safety Considerations
The 8.4% solution is extremely hypertonic (2 mOsmol/mL), which can cause hyperosmolar complications and compromise cerebral perfusion in critically ill patients. 3 This is why dilution to 4.2% concentration is recommended for vulnerable populations including pediatric patients and those at risk for osmotic injury. 3
Never mix sodium bicarbonate with calcium-containing solutions or vasoactive amines, as this causes precipitation or inactivation of catecholamines. 3, 4 Flush the IV line with normal saline before and after bicarbonate administration. 3