CO2 (Bicarbonate)
The CO2 blood test measures the level of bicarbonate in your blood, which helps indicate your body's acid-base balance. Most of the carbon dioxide in your blood is in the form of bicarbonate.
Category: Metabolic Panel
Also known as: co2, bicarbonate, hco3, carbon dioxide, total co2, tco2, Carbonic anhydride, CO2 TOTAL
Reference range: 23–29 mEq/L (Source: ABIM)
Standard unit: mEq/L
High values may indicate
High CO2 (bicarbonate) levels may indicate metabolic alkalosis, prolonged vomiting, COPD, or Cushing syndrome.
Low values may indicate
Low CO2 (bicarbonate) levels may indicate metabolic acidosis, kidney disease, diabetic ketoacidosis, or chronic diarrhea.
Frequently asked questions
- What is a normal CO2 (Bicarbonate) level?
- A typical reference range for CO2 (Bicarbonate) is 23–29 mEq/L (source: ABIM). Reference ranges vary by laboratory, age, and sex, so always compare against the range on your own lab report.
- What units is CO2 (Bicarbonate) measured in?
- CO2 (Bicarbonate) is most commonly reported in mEq/L. Labs in different countries may use other units — you can convert between them with BloodId's blood test unit converter.
- Where do CO2 (Bicarbonate) reference ranges come from?
- BloodId uses ABIM standard reference ranges and educational information from MedlinePlus (see our methodology). Reference ranges still vary by lab, age, and sex, so always compare against your own report.
- Can I track CO2 (Bicarbonate) over time?
- Yes. Upload results from any lab and BloodId charts your CO2 (Bicarbonate) over time against its reference range, so you can see whether the trend is rising, falling, or stable.
Related biomarkers
Source: MedlinePlus, U.S. National Library of Medicine
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