Oximetry questions

[yankees123]

  I have a few  questions if someone can answer.  What do the numbers in Oscar that are listed as Pulse changes and spo2 drop actually mean? Also what does the number in statistics section listed as pulse change index mean?  Also is there a wiki that goes over oximetry in detail?
Thanks

[ApneaQuestions]

Sorry I can't answer your question but I am thinking about maybe buying a compatible oximeter

Is there any chance you can upload a screenshot of your oximeter data so that I can see what I'd be getting if I did?

If you don't get any good answers I might be able to reverse-engineer what you are seeing.

[spacewrench]

There's settings in the Oximetry tab of Preferences for when OSCAR flags pulse changes and SPO2 drops.  I believe the events that are listed are created by OSCAR by looking through the oximeter data.  For the oximeter data formats I know about, there are no flags marked in the original data.

The attached screenshot shows part of my display, with pulse, SPO2 and movement from my pulse oximeter.

   

[PhoebeAnn]

A little oximetry trivia, re where to put the sensor: I had read somewhere that you should use "the index finger on the non-dominant hand." But the 50F "manual" shows it on the middle finger of the left hand. I asked Mr Google, and found a couple of authoritative articles:

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4627972/
A very scholarly article, rich in statistical magic: "In conclusion, SpO2 measurement from the fingers of the both hands with the pulse oximetry, the right middle finger and right thumb have statistically significant higher value when compared with left middle finger in right-hand dominant volunteers. We assume that right middle finger and right thumb have the most accurate value that reflects the arterial oxygen saturation."

For a slightly less academic treatment, a poster from (apparently) the Physical Therapy folks at Eastern Washinton University, Spokane, Washington; Google buried the URL during its search, but if you search for "Does finger used for pulse oximetry measurements make a difference?" (The title of the poster) you get a nice easy-to-read description of an experiment which showed: "Results: No significant difference was found for SpO2 or HR measurements among the 5 digits for any of the pulse oximeters. The thumb and pinky had greater error rates than the index, middle, and ring fingers. The results of this study suggest that pulse oximetry measurements should be taken at the index, middle, or ring fingers and that measurement taken at these middle digits are equivalent."

I use the middle finger on my left (non-dominant) hand, mostly because it's convenient.