Flow Limitations Full Face Mask vs Pillows

[wickedsleepy]

Hi everyone,

I'm going in to see my doc, today, so hopefully he will be able to give me some answers.  One thing I have noticed pretty consistently is that I sleep better with nasal pillows and mouth tape (when I can tolerate it, i.e. don't have congestion, etc.) versus the full face mask.  I feel better, I feel more rested, I don't have all the dizziness and vertigo and exhaustion that I can have when using the full face mask.  One of the reasons, from my other threads in this forum, I'm pretty sure is the flow limitations that seem to be much more of a problem with the full face mask.  I am told (and agree) that I have positional apnea... I get the pressure spikes, more issues, and more events when I roll on my back.  My FFM leaks much more, etc.  However, I don't seem to have this issue when I use nasal pillows and mouth tape.  I can be on my back or side and still get better results.

Does anyone have any theories as to why I get higher flow limitations and more issues with FFM versus nasal pillows?  Check out the flow rate graphs.  Anyone else experience this?  I would LOVE to be able to just use the pillows or a nasal mask, but I'm not there yet.  Some nights having my mouth taped shut leaves me feeling confused and dizzy in the morning.

Flow rate with nasal pillows
   

Flow rate with full face mask (Evora)
   

[Gideon]

By any chance are you using a pulse oximeter? Both charts maybe showing a cardiogenic osscillation. I'd need to see if those bumps match your heart rate to be sure

[Sleeprider]

That is a pretty remarkable difference between the nasal -nd full-face mask. Notice the significant difference in 95% and maximum flow rate? That shows the machine is counting each of those waves as a separate breath, and they are actually just a weak inspiration resulting from flow limitation and lack of spontaneous effort. The settings are very different with a pressure of 8-20 EPR 1 for nasal and 9.0 to 15.4 EPR 1 for full face. I would have suggested higher pressure for the full face, but you have that in place We can't see if you have the correct interface selected in settings. Actual realized pressure is much higher with FFM.

For nasal therapy, I recommend increasing minimum pressure by 1-cm and increasing EPR to setting 3. This should cut the 95% flow limits of 0.09 at least in half. With results like I'm seeing for FFM, I'm inclined to recommend you not use that, however, changing EPR to 3 may still help resolve the very high flow limits (95% of 0.18) that cause this chaotic breathing pattern. Without a view of the full-night therapy, I can't see whether positional apnea is playing a role here, but would be indicated by clusters of obstruction or flow limitation, with periods of normal breathing. https://www.apneaboard.com/wiki/index.ph...onal_Apnea

[wickedsleepy]

Thanks, both of you.  I wish I did have a pulse oximiter of some kind that could store results.  I've thought about purchasing one, but I just don't have the $.  Maybe I can borrow my wife's apple watch, if she can keep it charged haha.

Side-note.  I did have the pressure ranges the same around that same time-frame of the nasal mask graph (last month).  Since end of January, I've been experimenting with lowering the max pressure with the FFM to see if I can manage some of these leaks better and thus not have the straps need to be so snug.  It's not necessarily helped. I'm still getting some large leaks here and there, but I did notice that lowering the top pressure a) hasn't increased my AHI and b) hasn't really made me feel any worse.  In fact, I've had better days and lower AHI scores with a max pressure of 15.4 than at 20, though still enough bad days to feel like garbage much of the time.  My AHI with FFM at 15.4 max have been similar to what I had last night, which was 0.9.  Back when I had the MAX at 20, the AHI with my Evora mask was typically 2.5 up to 3.  Still this same wavy flow pattern that mimics rapid respiration rate, though.  Essentially, lowing the max pressure has chopped off the massive spikes I was getting while also not noticeably negatively impacting my therapy.  Weird.  

Back to switching to nasal-only therapy, what other options are there aside from tape?  The issue I have with the tape is that it's hard to get off.  If I wake up not feeling like I'm getting enough air, it's not easy to remove.  Of course, I WANT it to stay on to stop the mouth leaks, but I would much rather either some other device or even to learn how to keep my tongue from falling and thus keeping that "valve" closed for my mouth while I sleep. Chin straps just don't cut it.  What about those things that suction to your tongue and keep your tongue in place?  Seems that would not keep the airway through the mouth closed, though.  Hmm...

[wickedsleepy]

Weird. Gideon, I did look up the cardiogenic oscillation effect that you mentioned, and the "Cardioballistic artifact," and it sure LOOKS like that by looking at some of the sample graphs. I'm not sure what that means, though. I read that the cause is debated. Is it bad? I also wonder if it has something to do with a) air coming in also through the mouth and/or b) tension of straps pulling my lower jaw back while wearing FFM.