Assessing Bicarbonate | ABG Interpretation - MedSchool
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ABG Interpretation
 
 
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Bicarbonate is one of the major alkali present in the blood, and plays a crucial role in acid-base balance.
 

Assessing Bicarbonate

 
 
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Overview

  • Bicarbonate (HCO₃) is one of the major alkali present in the blood, and plays a crucial role in acid-base balance.
      • Normal Range

      • 22 - 26 mmol/L

Elevated HCO₃

  • An elevated bicarbonate level greater than 26 suggests the presence of a metabolic process - either primary (metabolic alkalosis) or secondary (compensation for respiratory acidosis).
    • Interpretation

    • Elevated pH with elevated HCO₃ - suggests metabolic alkalosis
    • Reduced pH with elevated HCO₃ and elevated PCO - suggests metabolic compensation for chronic respiratory acidosis
    • Normal pH with elevated HCO₃ and elevated PCO₂ - suggests mixed metabolic alkalosis-respiratory acidosis

Reduced HCO₃

  • A reduced bicarbonate level less than 22 suggests the presence of a metabolic process - either primary (metabolic acidosis) or secondary (compensation for respiratory alkalosis).
    • Interpretation

    • Reduced pH with reduced HCO₃ - suggests metabolic acidosis
    • Elevated pH with reduced HCO₃ and reduced PCO - suggests metabolic compensation for chronic respiratory alkalosis
    • Normal pH with reduced HCO₃ and reduced PCO₂ - suggests mixed metabolic acidosis-respiratory alkalosis
Last updated on February 7th, 2020
 
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