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Oxygen desaturation index

Breathing tests · also printed as ODI, Oxygen desaturation index, ODI 3%, ODI 4%, ODI (/hr)

Typical UK adult rangebelow 5 /hr

Below 5 per hour is typical.

What this test measures

The ODI counts how many times per hour the blood oxygen dips by a set amount (usually 3 or 4 percent) during sleep, measured from a finger probe.

Why doctors request it

Often the main number from a home sleep test, and used alongside AHI.

What commonly pushes it up

Sleep apnoea
Lung disease with low overnight oxygen
Alcohol and sedatives

What commonly pushes it down

Effective treatment of sleep apnoea
Supplemental oxygen

Everyday reasons for a value outside the range

The 3 percent and 4 percent versions give different numbers
A probe that slips gives artefact

About the sample

Overnight recording.

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.