Poor Coordination of CPAP and Oxygen Drop Data

[Lirich]

I am just starting my CPAP treatment and I assumed that there would be good coordination of data of Apnea events with oxygen saturation data drops recorded with a continuous finger pulse oxygen monitor.  That does not seem to be the case.  See attached Apnea event data recorded by my Resmed Airsense 10 and the results from my Wellue Continuous Ring Oxygen Monitor.   The Airsense recorded my only obstructive apnea for the night at 1:36 am.  My oxygen Ring showed my largest 4% drop to 90% saturation occurring a half hour later at 2:05 am.
Likewise, the hypopneas & clear airway apneas that occurred between 3:40 & 4:40 am were noted during a period of no SpO2 drops according to the oxygen monitor.  The Airsense 10 has given me an AHI of 9.14 when my oxygen ring monitor has recorded only 2 SpO2 drops of 3% for the entire night.   And then it measured an AHI of 1.96 when my oxygen monitor recorded 15 drops of 3% & 6 drops of 4%.  This does not make sense.  Can anyone share an explanation of why the oxygen drop results do not correlate with the apnea data?

Before I started by CPAP therapy, the Oxygen monitor was helpful in demonstrating that I get a much higher number of oxygen drops & drops below 90% saturation when sleeping on my back than on my side.   I thought it would be helpful in monitoring the effectiveness of my CPAP therapy as well.  Not so sure at this point.  Thanks for any insights. 

[attachment=29817]

[gregoryalter]

I have same devices as you, O2Ring and Airsense, and started my own thread before I found yours, so I am quite interested to see what we hear from experienced folks, here.  I run O2 Cleanup from the Data dropdown; have you done so and what is the effect?  Most so called events are eliminated once you get rid of movement artifact, it seems.  My desat occurs only as I fall asleep, which I am very curious about: 5 to 10 pts.

[Lirich]

Thanks for your post.  I read your thread and the replies you received.   Seems like others also see no SsO2 desaturation during apnea events.  Does not seem logical to me but perhaps someone will share some more insight on the reasons for this to better explain it.
 
Regarding your question about the saturation drop as you fall asleep, see the link below to the soft cervical collar wiki.  I noticed on some of my Oscar data that I had clusters of apneas at various times and the wiki on "soft cervical collars" relates these to a positional issue known as "chin tuck".   I think that this is why I have more apneas & oxygen denaturizations when I sleep on my back.  I decided to get one and try it out and see if it helps eliminate the clusters.    You may want to review this wiki and see if it applies to your situation.  I tried to post a link to it but the forum would not let me do so.  Apparently I do not have permission to add links yet.
I'm also a newbie and found that the wiki's on Optimizing CPAP Therapy and Soft Cervical Collars had a lot of useful information for new members.  Worth checking out.

[gregoryalter]

Thanks. Got a private msg link to cervical collar article. I am going to play with sleep position using a curved mem foam pillow that lifts chin up and back. If that works during first part of sleep, I may get a collar.

[OpalRose]

Here's the link for anyone that wants to read it.

http://www.apneaboard.com/wiki/index.php...cal_Collar