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pO2

Blood gases · also printed as PO2, PaO2, pO2 (arterial), Oxygen partial pressure, O2 (blood gas)

Typical UK adult range11 to 13 kPa

Ranges vary between laboratories; the range printed on the report takes precedence.

What this test measures

pO2 is the pressure of oxygen dissolved in the blood. On an arterial sample it shows how well the lungs are getting oxygen in.

Why doctors request it

Part of an arterial blood gas in breathing difficulty and when oxygen is being adjusted.

What commonly pushes it up

Breathing supplemental oxygen

What commonly pushes it down

Lung disease of any kind
Being at altitude
A venous sample, which is much lower and is not comparable
Poor circulation

Everyday reasons for a value outside the range

Venous pO2 is normally low and means something different
Values fall gently with age

About the sample

Interpreted with the oxygen being breathed at the time.

Written by a UK consultant physician. Typical UK adult reference ranges; your laboratory's own printed range takes precedence.

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This is an educational summary of results you uploaded. It is not medical advice, a diagnosis or a treatment plan, and it does not replace the doctor who requested the test. If you are worried, or a result is marked outside range, discuss it with your doctor. Written and reviewed by a UK consultant physician. Reference ranges vary between laboratories.