Bicarb Blood Test: Reference Range

Bicarb, short for bicarbonate, is a form of carbon dioxide (CO2) in the body. Therefore, bicarb blood test measures the level of CO2 in the body, so as to identify an electrolyte imbalance or acid-base (pH) imbalance.

Reference Range:

A normal range is 23 to 29 mmol/L.

What does the abnormal result mean?

A low CO2 level suggest the existence of:

  • kidney disease
  • Addison’s disease
  • aspirin overdose
  • diabetic ketoacidosis (the body doesn’t have enough insulin to digest sugar)
  • metabolic acidosis (too much acid in the body)
  • respiratory alkalosis (which can be caused by hyperventilation)
  • shock
  • ethylene glycol or methanol poisoning, which usually exist in antifreeze, detergents, paints, and other household products.

On the other hand, a high result suggests:

  • Severe, prolonged vomiting and/or diarrhea
  • Lung diseases, including COPD (chronic obstructive pulmonary disease)
  • Adrenal gland problems, such as Cushing syndrome and Conn syndrome
  • Metabolic alkalosis (too many bases in the body)


Keywords: Bicarb; Bicarbonate; Bicarbonate (Total CO2); Carbon Dioxide Content; CO2 Content; HCO3-TCO2; Total CO2

* The Content is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition.