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OSCAR Oximeter Statistics? - RadarRalfs - 04-15-2021

I was curious about blood oxygen levels so purchased an O2Ring which produces data that can be imported into OSCAR.  It seems to work well and comes with its own software (O2-Insight-Pro) which produces a summary report for each day.  OSCAR and O2-Insight-Pro seem to disagree on the Oxygen Desaturation Index (ODI), and also on the number of Drop Events.  Please see the images below which contain numbers for my most recent session.  OSCAR states a SpO2 Drop Index of 19.02 and counts 156 SpO2 Drop Events.  The Insight Pro software states a 3% ODI of 2.6 and a 4% ODI of 1.1 with a total of 30 (21+9) drops.

I was hoping that someone could explain this and would also like to know more about what is considered normal (or not).


PS: In an earlier post it was recommended to "attach the OSCAR screenshots via the forum New Attachment: Choose File. This way we view your data without need to download."  I had a quick look but couldn't find how to do this so am continuing to use the attachment function at the bottom of the "Post a new Thread" panel.


RE: OSCAR Oximeter Statistics? - Crimson Nape - 04-15-2021

I have the SleepU and use the same software as you.   I've never found a definition of what the 3% and 4% is calculated from, the overall average or the immediate preceding value?  How long a time period is it using before it classifies it as a drop?    OSCAR lists its parameters in the Preferences/Oximetry tab as a drop 3% for 8 seconds or more.  Since Viatom/Wellue devices record a data point every 4 seconds, that would be 2 consecutive points of data that dropped 3% below its predecessor.  

I don't bother with either one to be honest because a drop can be caused by bumping the sensor while moving or rolling over.  I look at the overall trend for any particular recorded session.    But, that's just me. . .


RE: OSCAR Oximeter Statistics? - RadarRalfs - 04-16-2021

Thanks - I hadn't noticed the OSCAR Oximetry Preferences.  The O2-Insight-Pro software just divides the number of drops by the number of hours to get the ODI but the definition of what is a "drop" is a bit unclear.  I suppose it might be just a continuous downward movement before it starts to go up again but you would think time would be a factor.

This article has some information: https://www.verywellhealth.com/oxygen-desaturation-index-3015362

"The degree of change from baseline can be measured in two different ways. The criteria used to determine the index may vary depending on the scoring rules used. According to guidelines from the American Academy of Sleep Medicine, any respiratory event during sleep with a 3% drop in blood oxygen levels is counted towards the total.
For example, a change from 95% to 92% would be an event that is counted toward the index's total.
However, Medicare and some other insurances still rely on older scoring rules and require a 4% change for an event to be counted toward the index."

My averages seem fine and the overall O2-Insight-Pro score is good (averaging 9.8/10).  However the vibratory alert is set at 88% and it does go off every week or so - very brief intervals though.  Just wondering what health implications that might have.

Dave H