Central apneas and tips to improve CPAP therapy

[jcp519]

Hi all!

I got my cpap (ResMed AirSense 11) around 4 months ago and it has helped my sleep quite a lot since I started using it. I feel much better than I did before starting, but I still do sometimes suffer from daytime sleepiness and would like some help with trying to improve my sleep more.

I was diagnosed with moderate sleep apnea with an AHI around 15-17. Since I started my AHI is consistently around 3-6 so I definitely feel like there is room for me to improve. I recently figured out how to get into the clinical menu of my cpap and noticed that most of my events are CA, with some hypopneas mixed in. I started changing some settings here and there, like turning off EPR since it was uncomfortable for me. My original pressure range was 4-20 which I read is far too wide. Based on some other posts on the forum I changed it to 6-9 as it seemed my pressures on OSCAR seemed to hover around there even when the range was set to 4-20.

I'm looking for some more advice on how I could tweak the settings to improve my sleep more and some advice on how to reduce the CA events that I'm still getting. I've attached a couple screenshots of what I would consider my average nights.

Thanks!

       

[Deborah K.]

It's great that you learned how to change your settings yourself.  Good for you!

I suggest you raise your low-pressure setting to 7 and your high-pressure setting to 13.  You are bumping up against the 9 way too much.  Did your sleep study show a lot of CAs?  That will help us figure out how to help you.  Posting a redacted copy of your sleep study would be helpful.

[jcp519]

It's great that you learned how to change your settings yourself.  Good for you!

I suggest you raise your low-pressure setting to 7 and your high-pressure setting to 13.  You are bumping up against the 9 way too much.  Did your sleep study show a lot of CAs?  That will help us figure out how to help you.  Posting a redacted copy of your sleep study would be helpful.

Thanks for the response. I'll try those pressure settings out. My sleep study was an at-home study so it actually doesn't show CAs... only OAs. I'll try to find the copy of it anyways and post it.

[jcp519]

Here's the redacted sleep study.



           

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Here's the redacted sleep study.

And the last attachment because I can only do 3 per post

   

[Sleeprider]

You have moderately high flow limitations and this is what is causing your pressure to bounce around. I'm pretty sure what is being flagged as CA is actually obstructed, flow-limited breathing. We could look closer, but the more constructive approach is going to be to revise some settings and fix the problems. You are currently at 6.0 to 9.0 pressure, and your median pressure is 8.2. You need to increase minimum pressure to 8.0, maximum pressure to 11.0 and turn on EPR full-time at setting 3. This will result in a bilevel pressure range of 8.0/5.0 to 11.0/8.0 (inhale exhale). This maintains your exhale pressure range or slightly lowers it, but gives you pressure support on inspiration. You will be surprised.

[jcp519]

I did the pressure changes that Deborah suggested a few days ago from 7-13 cmH2O. I'll post a screenshot of one of the nights with that which was 2/13. I can also try the bilevel pressure settings to see if that helps the flow limitations.

I also wanted to mention that I tried a cervical collar and mouth taping for the first time to help resolve the leaks and to see if its positional at all. I've posted the screenshots from 2/14 with the mouth taping/cervical collar.

I feel significantly more awake today and my AHI/CA events seemed to have went down. This makes me wonder if you're correct by saying the machine is flagging the events as CA's when they are actually somewhat positional OA events. I wonder if I tend to tuck my chin while asleep, but the machine flags them as CA events.

I still have some flow limitations though, so I'll adjust the EPR to help out with those.

I've attached a zoomed photo of one of the "CA" events to see if that is helpful.

[Sleeprider]

I would have probably picked out one of the double CA events at 02:00 or 02:15, but the event at 03:29:20 arises out of flow limitation going back to 03:26:30 and ending in an arousal with recovery breathing at 03:20:30.  The last breath in that recovery series has no expiration and the breathing pause is flagged as CA. Normal respiration resumes with clear flow limitation onset within a minute.  I wasn't there, but if I had to guess, you probably shifted position with a breath-hold after the arousal.

[jcp519]

Here's those double events. For now I'll take your advice and try those settings changes.


Thank you for your help by the way, much appreciated!

       

[Sleeprider]

The first one before 2:00 starts as flow limits which result in recovery breathing (hyperventilation) which triggers some "loop-gain" periodic breathing. So this one looks central from obstructive origins. The second on is pure obstructive where increasing flow limits lead to an apnea with very little flow, followed by recovery hyperventilation and a second apnea that may be central from CO2 loss. Resolving the flow limits that trigger these events and preceding hyperventilation would likely prevent them from occurring. In addition, if they were actually central, a higher trigger sensitivity could be used to stimulate a breath. Without higher pressure support to resolve flow limits, or trigger/cycle sensitivity controls to stimulate breaths during actual central events, we're much more limited in how we can address this.

[jcp519]

I appreciate you helping me to understand what going here. Again, I'll try out the settings you suggested and report back to see what happens. 

I do have an appointment with a sleep doctor in around a month, so I'll definitely discuss it with them. My old sleep doctor was useless other than getting me a machine, so hopefully the new one will be more helpful with resolving issues.