Reference ranges
CO2 (bicarbonate) reference range
Reference ranges describe the interval a laboratory prints next to your result. They are not a diagnosis of what is “normal” for you personally — your clinician interprets results in context.
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What CO2 (bicarbonate) measures
Labs measure total carbon dioxide in blood, which is mostly bicarbonate — a marker used alongside others to look at the body's acid-base status.
Why ranges differ
Laboratories set their own reference intervals using their methods, equipment, and population data. That is why the range on your Quest report may differ from a LabCorp report — always use the interval printed on your source document.
Common units
CO2 (bicarbonate) is often reported in mmol/L. Confirm units on your original report before comparing values across time.