Oxygen Saturation in Arterial Blood (by Microelectrode)
This test measures how much oxygen is bound to hemoglobin in your blood, specifically in the arteries. It’s often used to assess lung function and blood oxygen levels.
["Helps doctors check if your lungs are working properly and if your blood carries enough oxygen."]
Key facts at a glance
- LOINC
- 8852-6
- Short code
- SaO2 % MPA
- Synonyms
- SaO2 % MPA
- Category
- chemistry
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Specimen volume
- 5 mL
- Stability
- Room temperature: 4h, Refrigerated: 24h, Frozen: 7d
- Hemolysis max
- 500
- Lipemia max
- 1000
- Icterus max
- 500
- TAT
- 4–24 hours
- Order
- routine
Why This Test Is Done
Your doctor may order this test if you have symptoms like shortness of breath, fatigue, or if they suspect conditions like lung disease, heart problems, or exposure to low oxygen environments. It’s also used during surgeries, anesthesia, or in intensive care settings to monitor oxygen levels continuously.
How the Test Works
A small probe is inserted into an artery (usually in your wrist or groin) to measure oxygen saturation directly. This method provides real-time results and is highly accurate for assessing arterial blood oxygen levels.
What to Expect Before the Test
You may need to fast for a short period before the test, depending on your doctor’s instructions. You’ll likely be asked to lie still while the probe is inserted, and you may feel a slight pinch or pressure during the procedure.
What to Expect During the Test
The test itself is quick and usually painless. You might feel a brief sting as the needle is inserted, but the probe itself doesn’t cause discomfort. Once inserted, the probe stays in place for a short time to collect data.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Low oxygen saturation can indicate serious conditions like chronic obstructive pulmonary disease (COPD), pneumonia, heart failure, or even severe anemia. High saturation may sometimes suggest conditions like polycythemia (too many red blood cells) or certain medications. Continuous monitoring helps doctors adjust treatments like oxygen therapy or manage underlying health issues.
Short name
O₂ Saturation (Microelectrode)
Frequently asked questions
Is this test painful?
How long does it take to get results?
Can I eat or drink before this test?
Sources
- 1
- 2Lab Tests OnlineSource
- 3
Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.
This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.
Medically reviewed by WellAlly Editorial Team Last reviewed August 16, 2026. · Read our editorial policy