{"id":"po2-arterial","name":"Arterial pO2","shortName":"Arterial pO2","aliases":["pO2, Arterial","PaO2","pO2 (ABG)","Oxygen Partial Pressure, Arterial","Arterial pO2","pO2 (Arterial)","Arterial oxygen tension","Oxygen tension, arterial","Partial Pressure of Oxygen, Arterial","ABG pO2","pO2 arterial"],"abbreviations":["PaO2"],"loinc":[{"code":"2703-7","primary":true},{"code":"11556-8","primary":false},{"code":"2704-5","primary":false}],"specimen":"whole-blood","units":[{"ucum":"mm[Hg]","display":"mmHg"},{"ucum":"kPa","display":"kPa"}],"referenceRanges":[{"population":"Adults","low":75,"high":100,"unit":"mm[Hg]","unitDisplay":"mmHg","note":"Adult arterial interval while breathing room air at sea level. MedlinePlus and one review print 75 to 100 mmHg; another review prints 80 to 100 mmHg (10.6 to 13.3 kPa). Lab directories print higher upper limits and, in some, lower limits for older adults: 83 to 108 mmHg at Penn State Health, 74 to 108 at Northwell Health, and at OHSU 83 to 108 up to age 40 and 72 to 104 above age 40. Values above 100 are expected when you are breathing extra oxygen and are not a concern by themselves. Healthy people at altitude run lower (median about 70 mmHg at 3,164 m in 46 residents). Use the range on your own report first. Adults only; newborn and child values 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://pennstatehealth.org/pathology-test/blood-gas-arterial","publisher":"Penn State Health"},{"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"}]},{"population":"75+","low":68.4,"high":null,"unit":"mm[Hg]","unitDisplay":"mmHg","note":"Lower limit only. In 194 healthy nonsmokers aged 40 to 90, PaO2 fell with age up to the 70 to 74 group, and the trend then reversed. In those 75 and older the mean was 83.4 mmHg (SD 9.15) and the 5th percentile was 68.4 mmHg. This is one study, so treat it as context for older adults and use the range on your own report first. OHSU's lab directory prints 72 to 104 mmHg for everyone over 40.","sources":[{"title":"Reference values of arterial oxygen tension in the middle-aged and elderly","url":"https://pubmed.ncbi.nlm.nih.gov/7663806/","publisher":"American Journal of Respiratory and Critical Care Medicine","year":1995},{"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":"How much oxygen is dissolved in your arterial blood. It shows how well your lungs move oxygen into your blood.","url":"https://bloodtesttracker.com/markers/po2-arterial","notice":"Information, not medical advice. Ranges differ between labs, so the range on your own report is the one your result is judged against."}