Bicarbonate Deficit Calculator
Calculate bicarbonate deficit for metabolic acidosis management and sodium bicarbonate replacement therapy
Calculate Bicarbonate Deficit
Critical Care Medical Calculation
This calculator is for qualified healthcare professionals only. Bicarbonate replacement therapy requires careful monitoring and should only be administered under medical supervision. Results must be correlated with clinical condition and arterial blood gas analysis.
Patient body weight
Current serum bicarbonate level
Target bicarbonate level (typically 24 mEq/L)
Clinical replacement approach
Bicarbonate Deficit Results
Enter values to calculate deficit
Bicarbonate Deficit Formula
Critical Safety Guidelines
Severe alkalemia, hypocalcemia, hypernatremia, volume overload
No more than 1-2 mEq/kg/hour to prevent rapid pH changes
Serial ABG, electrolytes, and neurological status
Example Calculation
Clinical Scenario
Patient: 70 kg adult
Current HCO₃⁻: 18 mEq/L
Target HCO₃⁻: 24 mEq/L
Deficit: 210 mEq
Calculation Steps
Deficit = 0.5 x 70 kg x (24 - 18)
Deficit = 0.5 x 70 x 6
Deficit = 210 mEq
Conservative: 105 mEq initially
Normal Values
Serum Bicarbonate
22-28 mEq/L (mmol/L)
Arterial pH
7.35-7.45
PCO₂
35-45 mmHg
Common Causes
Understanding Bicarbonate Deficit
What is Bicarbonate Deficit?
Bicarbonate deficit occurs when serum bicarbonate levels fall below the normal range (22-28 mEq/L), typically indicating metabolic acidosis. This condition can result from various causes including diabetic ketoacidosis, kidney disease, severe diarrhea, or poisoning.
Clinical Manifestations
- •Kussmaul respirations (deep, rapid breathing)
- •Fatigue and weakness
- •Nausea and vomiting
- •Altered mental status
Replacement Therapy
Deficit = 0.5 x Weight (kg) x (Desired HCO₃⁻ - Actual HCO₃⁻)
Where:
- 0.5 = Distribution factor for bicarbonate
- Weight in kilograms
- Desired HCO₃⁻ typically 24 mEq/L
- Actual HCO₃⁻ from blood gas or chemistry panel
Clinical Pearl: Only replace 1/3 to 1/2 of calculated deficit initially, as overcorrection can cause metabolic alkalosis and paradoxical CSF acidosis.
Sodium Bicarbonate Solutions
8.4% NaHCO₃
Concentration: 1 mEq/mL
Use: Critical care, emergency
Caution: Hypertonic, requires central line
7.4% NaHCO₃
Concentration: 0.89 mEq/mL
Use: General ward administration
Benefit: Nearly isotonic
4.2% NaHCO₃
Concentration: 0.5 mEq/mL
Use: Pediatric patients
Benefit: Lower osmolarity
Treatment Considerations
Indications for Treatment
- • Severe metabolic acidosis (pH < 7.1)
- • Hyperkalemia with acidosis
- • Hemodynamic instability
- • Tricyclic antidepressant overdose
Contraindications
- • Respiratory acidosis without ventilation
- • Hypocalcemia or hypernatremia
- • Volume overload or heart failure
- • Unknown cause of metabolic acidosis