Air building up in your mouth: where does it go if you tape your mouth shut?

[Albigensian]

Hi.

I'm working on how to fine-tune my setup.  I am puzzling over the air that sneaks into my mouth, gets trapped there, and struggles to get out through my (closed) lips.

Here are my two questions:

(1)  In Oscar, does the measurement of leaks measure air lost through the mouth?   I have been assuming that the leak data relates to mask leaks.   The OSCAR guide starts off talking about mask leaks and mostly sticks to discussing masks, so I jumped to the conclusion that the leak data is (somehow) only about how well the mask/pillow/whatever is doing.    Does the leak date include all leaks, including air that leaks out through the mouth?   If I understand the logic of leak measurement, I believe that it does.  I didn't think about this until recently, though, so I am not sure.    Experts, do you know?

(2) Tape is often advised as a way of dealing with mouth breathing.   If I tape my mouth shut, does that do anything to reduce leakage from air forced into my mouth and eventually finding a way to escape through my 3M Micropore tape?    Or does my tape just slow the escaping air down to a dribble so that some or most of it gets pushed back into the channel from nose to lungs? 

The Micropore tape was recommended by a couple of more experienced users on this board.   It is not as impermeable as duct tape, so air bubbles through the tape and also dribbles out the side of the taped mouth close to the line of the lips.    If this is happening, is it making it harder for my machine to do what it needs to do to lessen my events?   

I could look for an impermeable tape or put on layers of the permeable-but-easy-to-remove tape but I don't know if it would be a good thing to entirely lock my mouth shut.   Where would the air go after it has built up in my mouth?   Would it be forced back into the channel between nose and lungs?   Would my head blow up?     In my experience, it rolls around in my mouth looking for an exit and that, of course, wakes me up.    I have a feeling that even the slow dissipation of the accumulated air through the permeable tape damages the quality of my sleep but I am not sure what to do.

I have been taping my mouth to prevent air from escaping through it more than to keep me from opening my mouth to inhale or exhale through it.  I don't tend to do much or any actual mouth breathing.   I just leak air if it gets forced into my mouth because ..... well, I'm not exactly sure of the "because."  I know it has something to do with more air than can be handled by the channels that go from the nose to the lungs, probably associated with something physically sagging and limiting the volume that can be handled, but I'm not sure what I can do about it.    Apparently, I am not very good at getting a lock at the back of my throat;  I work on pressing the tongue behind the teeth to keep the airways closed, but I tend to let go of that during sleep.   I wear a chin strap to prevent my jaw from sagging down but it isn't strong enough to lock my mouth shut.   

I am looking into full face masks, as that might be the way that I need to go, but I've read enough to know that it's a real challenge to get a good fit -- and my local DME is no help, as they've not got much available to even look at.    So, I'm trying to see if I can cut down the leaks even with nasal pillos.

NOTE:  I do have another thread open about my sleep issues (Brain fog, lack of energy -- why did dropping my EPR make such a difference) and will be posting to it in a week or so, once this period of experimentation with setting is over, but this question seemed like it was sufficiently different from that thread to justify a new thread.    Let me know if I'm wrong about that.B[b]auch a difference?[/b]

I need to sleep on my back because of pain issues, even though my limited experiments seem to show that this problem is less acute when I sleep on my side.

I enclose two recent nights of data   Taped the same way both nights.    The settings are the same except for EPR.   

One was a pretty good night of sleep:   AHI 1.98, EPR 3 and I don't remember many episodes of air being forced into my mouth:  95% leak rate is 8.4 and flow limits are .08.  My notes on that night say that the nasal pillow was hissing more than usual, so I was attributing the leaks to that.  

The other was a truly horrible night of sleep.  It has AHI 4.04,  EPR 2, and I remember many episodes of air being pushed into and building up in my mouth:   95% leak rate is 16.8 and flow limits are .15.   I was constantly adjusting the nasal pillow and it never seemed to fit right.  (Different nasal pillows, with about the same weeks of use, on these two nights.)   So, it is possible that the leaks on the 4.04 night were all leaks involving the fit of the nasal pillows but I am wondering if those big numbers also have to do with the frequent hissing of air as it slowly dribbled out of my mouth and through my somewhat-permeable tape.  

And, yes, I know:  the takeaway from this experiment with a lowered EPR shows that it is a bad, bad idea.  Lowering EPR created a spray of OA's and I am sure it contributed to the buildup of air in my mouth.  So, I will be going back to 3.  Even at 3, though, I do have a bit of air leak through the mouth.  So, I'd like to understand it a bit better.

I'd appreciate any answers/suggestions/insights/corrections or links to where I can learn more about this.  Thanks!

          

[staceyburke]

Your leaks are NOT high enough to cause problems. The bottom chart shows positional apnea. Positional apnea is caused when your chin drops to your Sternum and cuts off your airway. There is NO changes you can make on your machine to stop it. You can only stop it by staying out of that position. 

You said you sleep on your back and that makes it much easier for you to chin tuck. You can try a flatter pillow but you may need a collar to stay out of that position. I have a link in my signature to collars. In it they have examples of people with and the same people with the collar. 

I suggested you move to EPR 3 before and I still believe you will do better at 3. Your flow limits are still to high.

[Albigensian]

Thanks, SB, for looking at the leak data. Can you tell me what was the clue about a positional problem so that I can learn how to recognize it in my data?

Yes, I have been using 3 EPR and inching up my min pressure as you suggested. The 2 was a one night experiment. Does it make sense to you that dropping EPR would have led to a lot more mouth leaks? Or was last night's explosion of mouth leaks due to a positional problem that both upped my OA events and narrowed the channel between nose and lungs sufficiently to force air into my mouth?

I sleep with a small roll under my neck and a tiny bit of flat padding (not a pillow) under my head. Basically, I just make sure that I keep the natural curve of the cervical spine.

I do have a supportive collar. I think it was the one that you recommended in another person's thread. (I've been lurking for months.) I wore it for about two weeks and didn't see any difference in my outcomes but I will try it again and report back. Maybe it will make a difference now that I've got my min pressure and EPR adjusted.

I'm still trying to understand what the tape does for mouth leak. Is it doing its job if the air still seeps out because the tape is permeable?

Thanks again. I feel as if I'm making progress in figuring things out! It really is a thousand small things, isn't it? And no sleep doc or DME staffer has any interest in any of them. As long as the AHI is under 5, they keep assuring me that I'm doing just fine. Aaargh! I'm very grateful to the many folks who share their insights on this board.

[SevereApnea]

Hi Albigensian

Higher pressures cause more leaks.

On your night of EPR 2 you had a higher AHI and lots of clusters of OA.
Apart from the positional issue already discussed, what I see is this:

Because your EPR of 2 did not treat the FL as well, the machine was trying to take the pressure higher.
It couldn't, your max was set at 12. 
You were bouncing off the 12 cmH20 mark in the later parts of the night from 06:30 to 08:30 and staying there for longer than you would want to be. Your leaks were higher in that session.

Note your 95% EPAP on your EPR=3 night is only 8.28 and on your EPR=2 night is 9.98.

If you break down the data on your sessions I suspect that you will see a significant difference between FL, leaks and achieved pressures between Sleep Session #1 and #3.

I like to set my Max Pressure a bit higher than I generally need, that way when it does need to go that high it only stays there a short while and not for hours on end. That minimizes my Time at (higher) Pressure and the effects of that.

This is just another piece to what you correctly call a puzzle, a 1000 piece puzzle (we like the WASGIJ ones)

Hope it helps.

[DaveCar]

I am looking into full face masks, as that might be the way that I need to go, but I've read enough to know that it's a real challenge to get a good fit -- and my local DME is no help, as they've not got much available to even look at.    So, I'm trying to see if I can cut down the leaks even with nasal pillos.

I didnt even try pillows when I started because I knew I would drop my mouth open and I didnt want to start taping my mouth closed. My original Rx was for 18cm, so I knew even a chin strap wouldnt work well.. that I would motorboat my lips or such.
I started with a full-face but I really didnt like the pressure on the nose bridge, it closed off my nasal and forced me to mouth breathe. Then I found the F30.  Perfectly able to push up on the nose a bit sorta like pillows, plus I have the bottom edge pushing on my lower jaw which keeps my mouth closed fairly reliably.

[Albigensian]

Thanks.   That's another piece of my puzzle.  I went back over my records from the past month (w/ Min Pr 8.8 or 9 and max at 12 with EPR at 3) and found a couple of nights where I did hit 12.   So, I'll inch up my max pr to a bit more than 12 to avoid that in the future.

Here's last night:   Min Pr 9, max Pr 12, EPR 3.  Taped, with cervical collar.  Not a bad night, but I did have a weird clump of AO's as I was falling asleep.   Maybe I was adjusting to the cervical collar, as I am returning to it after being told that some of my issue (on the high AHI/lousy sleep night I posted at the start of the threat) was positional.   (BTW, I still don't know how to recognize positional apnea:   do you know?  Is it just a tight cluster of events?  Is there any other clue?)

The leak rate seems a bit high, but I might be misled by the change in the y axis.   I have no idea why but shifts in its metric from night to night -- so, last night, the y axis was 0 to 23 and the night before it was 0 to 85).    I don't think I had a lot of buildup in my mouth last night but I did have some.   I think some of the problem was the nasal pillow.   When my min pr was low (due to a dumb DME starting me out at min 5 max 15 epr 3, I had much lower leak rates.    Advice on the board has gotten me better sleep by upping my min pressure (from 7 to 8 to 8.4 to 8.8 and finally 9) while keeping EPR at 3.   But the data show that my leak rate keeps going up.    Maybe the higher pressure loosens the nasal pillow's seal?  Maybe the higher pressure increases the chances of air being forced into my mouth and slowly hissing out through my closed (now, taped) mouth?  (The tape is permeable, so a slow hiss can release the pressure in the mouth.)  I dunno.   I'm still looking into a full face mask but know that isn't a magical solution.

   

[Albigensian]

Davecar,  I'm looking at the F30 pretty seriously.   Thanks for sharing your experience.

[Gideon]

The numbers in the above chart are very good so you have no need to add a correction..
Between 0115 and 0130 you have a cluster of obstructive events. These being so close to the start of the night may not be valid but it is that type of cluster that indicates positional apnea.
This one is small enough to ignore no matter when it occurs.

[mesenteria]

Your machine is a dynamic instrument that operates to keep pressures at presets.  If there are leaks of any kind, it will compensate, but only up to a maximum.  When there are leaks, it will up flow to maintain pressure.

Whether your mouth is closed or open, in a mask or not, it becomes part of the adaptive volume for the machine.  The machine's fan will reach a speed where it can maintain that dynamic equilibrium between flow and pressure.  If you are using a nasal mask or a nasal pillow, but don't tape, and your mouth opens at times, the machine must compensate by increasing flow.  If you tape, with almost no appreciable leakage, the machine will only provide the volume of air needed to reach and to maintain its presets.

You asked about where the air goes if your mouth is taped, but the volume at least partially enters your mouth.  It does where all the air entering your airway system goes....in and out.  If you tape, but open your oral cavity by relaxing your pharynges and your tongue, air will swirl around in your mouth and be expelled back up through your nose, just as your exhalation exhaust must do.  All air that you intake, that doesn't leak out from an unwanted exit, must, de facto, exit back the way it came.  That means what you find expanding your cheeks must also find its way out, but in vortices and flow in rhythm.

Unfortunately, many of us swallow some of the air, but now it has two apertures from which to exit.  Either one is impolite in some circles.

[CorruptAlligator]

Interesting topic, I recently noticed that I have minor amount of air that somehow gets into the mouth, and didn't notice this before.

It's not a huge leak where one opens mouth and burst of air shoots out. It's quite minor that a small burst of air gets inside the mouth if I have my mouth closed, but also leaks every so slight with my mouth slightly open. When I look on OSCAR, it's a minor amount of leakage to even detect by the machine.

The issue is, it causes awareness and thus, arousal. Since this can happen with lips closed, tape would trap the air still in the mouth.

I will experiment with tape and see if it prevents from larger leaks. Another annoyance of using CPAP machine. So many things that comes with CPAP usage that I can't wait to stop using it. I'm trying to lose enough weight and see if I can stop it's usage.

My issue of 'chin-tuck' seems to be attributed to full-face mask usage. In actuality, it's feel more constrictive in breathing with a collar, although the OSCAR chart shows good numbers. By using nasal mask, I don't need to wear a collar. I'm not too sure if it's 'chin-tuck,' in my case. In my case, it's likely jaw being pulled downward from the bottom straps on the full face mask. It's also a possibility that the FFM strap system is causing my head to tilt downward as well. It has something to do with the bottom portion mask (which nasal mask excludes) or the bottom straps.