{"id":"bicarbonate-blood-gas","name":"Bicarbonate (HCO3-), Blood Gas","shortName":"HCO3 (blood gas)","aliases":["Bicarbonate, Calculated","HCO3 (Actual)","cHCO3","Calculated Bicarbonate","Bicarbonate, Arterial","Bicarbonate, Blood Gas","Bicarbonate (ABG)","HCO3 (ABG)","HCO3, Arterial","Arterial HCO3","Actual Bicarbonate","Calculated HCO3","cHCO3-(P)"],"abbreviations":["cHCO3"],"loinc":[{"code":"1960-4","primary":true},{"code":"14627-4","primary":false},{"code":"1959-6","primary":false},{"code":"1961-2","primary":false}],"specimen":"calculated","units":[{"ucum":"mmol/L","display":"mmol/L"},{"ucum":"meq/L","display":"mEq/L"}],"referenceRanges":[{"population":"Adults","low":22,"high":26,"unit":"mmol/L","unitDisplay":"mmol/L","note":"Adult arterial interval of 22 to 26 mmol/L (MedlinePlus prints it as mEq/L, which is the same number). Venous blood runs about 1 mmol/L higher (23 to 27 in one review). Some lab directories print wider limits (21 to 29 mmol/L at Northwell Health Labs; 21 to 28 mmol/L for arterial samples at OHSU). Healthy people living at altitude run lower (median 21.6 mmol/L at 3,164 m in 46 residents). This is the value calculated on a blood gas. The 'CO2, total' or 'bicarbonate' on a chemistry panel is a separate measurement with its own range. Use the range on your own report first. Adults only; newborn and child ranges differ and are not included.","sources":[{"title":"Arterial Blood Gas (ABG) Test","url":"https://medlineplus.gov/lab-tests/arterial-blood-gas-abg-test/","publisher":"MedlinePlus, National Library of Medicine"},{"title":"Mastering blood gas interpretation: A practical guide for primary care providers","url":"https://doi.org/10.4102/safp.v67i1.6058","publisher":"South African Family Practice","year":2025},{"title":"Blood gas analysis: Clinical applications, interpretation and future directions (Review)","url":"https://doi.org/10.3892/mi.2025.291","publisher":"Medicine International","year":2026},{"title":"Arterial blood analysis of healthy residents in Huamachuco, Peru (3,164 m): a cross-sectional study","url":"https://doi.org/10.12688/f1000research.134567.2","publisher":"F1000Research","year":2023},{"title":"Blood Gas Arterial","url":"https://labs.northwell.edu/epic/test/114134","publisher":"Northwell Health Laboratories"},{"title":"Blood Gases, Comprehensive","url":"https://www.ohsu.edu/node/5762646","publisher":"Oregon Health & Science University (OHSU) Laboratory"}]}],"review":{"status":"ai-verified","label":"AI-verified against cited sources. Awaiting expert review","lastReviewed":"2026-10-03"},"summary":"The bicarbonate your blood gas analyzer calculates from pH and pCO2. It shows the kidney-controlled side of acid-base balance.","url":"https://bloodtesttracker.com/markers/bicarbonate-blood-gas","notice":"Information, not medical advice. Ranges differ between labs, so the range on your own report is the one your result is judged against."}