What is the recommended infusion rate for Sodabicarb (sodium bicarbonate)?

Sodium Bicarbonate Infusion Rate

For severe metabolic acidosis or sodium channel blocker toxicity, administer an initial IV bolus of 1-2 mEq/kg (typically 50-100 mL of 8.4% solution) given slowly over several minutes, followed by a continuous infusion of 150 mEq/L solution at 1-3 mL/kg/hour if ongoing alkalinization is needed. 1, 2, 3

Initial Bolus Dosing

Standard Metabolic Acidosis

• Adults: 1-2 mEq/kg IV administered slowly over several minutes 4, 3
• Pediatrics: 1-2 mEq/kg IV given slowly (use 0.5 mEq/mL concentration for infants under 2 years) 1, 2
• For cardiac arrest specifically, the FDA label recommends one to two 50 mL vials (44.6-100 mEq) initially, repeated every 5-10 minutes as indicated by arterial pH monitoring 3

Sodium Channel Blocker/TCA Toxicity

• Initial bolus: 50-150 mEq using hypertonic solution (1000 mEq/L), titrated to resolution of QRS prolongation and hypotension 1, 2
• The American Heart Association strongly recommends (Class I) this approach for tricyclic antidepressant poisoning with life-threatening cardiotoxicity 1
• Maximum cumulative dose: Do not exceed 6 mmol/kg to avoid hypernatremia, fluid overload, metabolic alkalosis, and cerebral edema 5

Continuous Infusion Rate

Maintenance Infusion

• Prepare: 150 mEq/L solution (dilute 8.4% bicarbonate appropriately) 1, 2
• Infusion rate: 1-3 mL/kg/hour 1, 2
• Continue infusion to maintain arterial pH ≥7.30 in severe acidosis or sodium channel blocker toxicity 1, 6

Diabetic Ketoacidosis (DKA) Specific Rates

• pH 6.9-7.0: Infuse 50 mmol sodium bicarbonate in 200 mL sterile water at 200 mL/hour 2, 4
• pH <6.9: Infuse 100 mmol sodium bicarbonate in 400 mL sterile water at 200 mL/hour 2, 4
• Bicarbonate is NOT recommended for DKA if pH ≥7.0 2

Less Urgent Metabolic Acidosis

• For older children and adults: 2-5 mEq/kg over 4-8 hours, depending on severity 3
• The FDA label emphasizes stepwise therapy since response is not precisely predictable 3

Critical Concentration Considerations

Pediatric Dilution Requirements

• Infants <2 years: Must use 0.5 mEq/mL (4.2%) concentration 2, 7
• Dilute 8.4% solution 1:1 with normal saline or sterile water to achieve 4.2% 2
• Children ≥2 years and adults: May use 8.4% solution, though dilution is often performed for safety 2

Isotonic vs Hypertonic Solutions

• Standard 8.4% solution is extremely hypertonic (2 mOsmol/mL) 2
• For contrast nephropathy prevention or when hypertonicity is a concern, isotonic bicarbonate (150 mEq/L) is preferred, though no commercial preparations exist in the US 2
• The 4.2% concentration reduces risk of hyperosmolar complications that can compromise cerebral perfusion 2

Monitoring Requirements During Infusion

Frequent Laboratory Monitoring (Every 2-4 Hours)

• Arterial blood gases: Monitor pH, PaCO2, and bicarbonate response 2, 4
• Serum electrolytes: Assess sodium (target <150-155 mEq/L), potassium, and ionized calcium 1, 2
• Target pH: Aim for 7.2-7.3, NOT complete normalization; avoid pH >7.50-7.55 1, 2

Ventilation Requirements

• Ensure adequate ventilation BEFORE administering bicarbonate, as it produces CO2 that must be eliminated 2, 4
• For sodium channel blocker toxicity, hyperventilation to PaCO2 30-35 mmHg works synergistically with bicarbonate to achieve alkalinization 5
• Without adequate ventilation, paradoxical intracellular acidosis can occur 2

Administration Technique and Compatibility

IV Line Management

• Flush IV line with normal saline before and after bicarbonate administration 2
• Never mix with calcium-containing solutions, vasoactive amines, or catecholamines (causes precipitation/inactivation) 2, 7, 4
• Administer through separate IV lines from blood products 7

Rate of Administration

• Give initial bolus slowly over several minutes, not as rapid push 2, 3
• In cardiac arrest, more rapid administration may be necessary, but caution is advised due to hypertonicity 3

When to Stop or Adjust Infusion

Discontinuation Criteria

• Target pH of 7.2-7.3 achieved 2
• Resolution of QRS prolongation and hemodynamic stability in toxicity cases 2
• Serum sodium exceeds 150-155 mEq/L 1, 2
• pH exceeds 7.50-7.55 1, 2
• Development of severe hypokalemia 1

Dose Adjustment

• Further bicarbonate administration should be guided by repeat arterial blood gas analysis, not given empirically 2, 3
• The FDA label warns against attempting full correction of acidosis within the first 24 hours due to delayed ventilatory readjustment 3

Special Clinical Scenarios

Cardiac Arrest

• The American College of Cardiology recommends against routine use in cardiac arrest 1, 2
• Consider only after first epinephrine dose fails, or in specific situations: documented severe acidosis (pH <7.1), hyperkalemia, or TCA/sodium channel blocker overdose 2, 3

Sepsis-Related Lactic Acidosis

• The Surviving Sepsis Campaign explicitly recommends against bicarbonate for hypoperfusion-induced lactic acidemia when pH ≥7.15 2
• Two randomized trials showed no difference in hemodynamic variables or vasopressor requirements compared to equimolar saline 2

Hyperkalemia

• Use as temporizing measure while definitive therapy is initiated 2
• Combine with glucose/insulin for synergistic potassium-lowering effect 1, 2

Common Pitfalls to Avoid

Excessive Dosing

• Do not continue dosing until QRS <100 ms in sodium channel blocker toxicity—stop after achieving pH 7.45-7.55 5
• QRS prolongation takes hours to normalize even with successful treatment 5
• Exceeding 6 mmol/kg cumulative dose risks life-threatening complications 5

Adverse Effects from Rapid/Excessive Administration

• Hypernatremia and hyperosmolarity: Monitor sodium closely 1, 2
• Hypokalemia: Bicarbonate shifts potassium intracellularly; monitor and replace 1, 2
• Hypocalcemia: Decreased ionized calcium can worsen cardiac contractility 2
• Metabolic alkalosis: Overshoot alkalosis delays ventilatory readjustment 3
• Fluid overload: Particularly concerning in cardiac, hepatic, or renal dysfunction 7

Inadequate Ventilation

• Administering bicarbonate without adequate ventilation causes paradoxical intracellular acidosis from CO2 accumulation 2, 4
• This is especially critical in non-intubated patients 4

Wrong Clinical Indication

• Bicarbonate does NOT improve outcomes in most forms of metabolic acidosis when pH ≥7.15 2
• The best treatment is correcting the underlying cause and restoring adequate circulation 2