Leak/Mask Fit Issues

[jkrm]

I have been on CPAP for almost 20 years, doing pretty well most of that time. I think I was one of the first users of the ResMed P10 nasal pillow mask, and for years thought it the perfect mask. In Spring of 2020, I got a new ResMed AirSense 10 AutoSet, and started using the myAir app. Most nights my score was in the high 90s, knocked down only by my getting up 4 or 5 times a night to use the bathroom. My mask seal rating was almost always 20 (out of 20), occasionally dropping to 17. 

But lately I have been having some problems. The P10 started irritating the inside of my left nostril, sometimes causing a lot of pain. I used Lansinoh cream to alleviate that, but also saw my mask seal ratings drop to 12 or 13 most nights and my wife started complaining about hearing noises that I think were probably leaks, starting at about 4 or 4:30 in the morning. The mask seemed like it just didn't want to seal properly and from that point on in the night I seemed to be struggling with it. I tried switching to the ResMed N30 and that helped somewhat, with the mask seal rating now about 15 on average. Also, my average AHI dropped from about 3 with the P10 to about 2 with the N30. All seemed pretty good, except that most nights, at about 4 AM, the leaks would start and the constant sleep interruptions to deal with them would mess up my sleep for the rest of the night, leaving me feeling tired in the morning.

My doctor suggested trying the Fisher-Paykel Evora nasal mask, which is similar to the N30 but has a more robust headgear. I've used the Evora 7 times now, with the average seal going to 17 and the average AHI dropping to 1.3 (!), but I am having the same issue at about 4 or 4:30 AM.

Last night I put an SD card into my machine and I tried OSCAR for the first time. I am going to try to attach a screenshot. You can see three big leak incidents, corresponding to rises in pressure, and then massive numbers of leaks starting at about 4:20 AM (and a big increase in pressure at the same time). This was with the N30.

So, sorry about the long build up, but this finally leads to my question: what could be causing the leak rate to so suddenly increase at about 4:30 AM? From what I can tell, both from my almost-nightly struggles and my wife's complaints, this seems to be happening almost every night. And it happens with all three masks: the P10, the N30, and the Evora.

One other question: my max pressure is set to 14. Since this is an APAP, I am not sure why the max pressure would be relevant, but I read somewhere that even with an APAP a too-high pressure can cause mask leaks. Should I try changing that setting?

Thanks!

[OpalRose]

Looking at the leak rate graph, I see mouth breathing (flat tops) and mask movement (spikey areas).  

Read through the Mask Primer

You may be able to get some hints and ideas on size and fit. If you're not able to control the leaks, you may need to move on to a full face mask. But try a few other things first.

It seems that you have sleep disruptions a good part of the night, even when there are no leaks or apnea events.

The flow limitations are higher than should be. This can and does cause the pressure to rise, especially when leaks are also involved. Work on the leaks, but if you want less sleep disruptions, the flow limitation needs to be lower.

The way to lower FL is to use EPR. EPR isn't working for you as your pressure is set to low.
To stop the up and downs we see on the pressure graph, please consider these changes:

Minimum pressure 7cm, Maximum pressure at 12cm. Set EPR to 2.

I think you will find this comfortable with any of the masks you are trying and should lower flow limitation, hypopnea, and reras.

[jkrm]

Thanks! I am going to try the changes in settings on my machine that you suggested. Probably try a cervical collar, too. I'd never heard of that but the explanation on the mask fit page makes sense, and I think I do tend to tuck my chin when I sleep.  I tried a full face mask once but it was a disaster, as was every "traditional" nasal mask I tried (the ones that cover the entire nose). I think I have too bony a face because they just don't seal.

[jkrm]

The changes you suggested (min set at 7, max at 12, EPR at 2) seem to have helped a lot. Last night, using the Evora, I got my mask seal rating back up to 17 and my AHI down to 0.4, much lower than it has been averaging. I only woke up 3 times (once due to a leg cramp) and my wife said that there was a lot less noise. I noticed that I had the Evora headgear adjusted so that it sat too low on my head and irritated my ears, which might have caused shuffling about leading to leakage. But this was only one night, so it's not a trend. I'll keep these settings for the next few days and see how it goes. Thanks for the suggestions!

[OpalRose]

You are welcome. I hope this continues to work for you. If you have any concerns, feel free to post another chart.