Mask Leaks at Higher pressures

Do masks have a rated pressure over which their performance is compromised?

During my titration study my readigns were Median 10.2; 95th Percentile 12.4 and Maximum 14.0 (using a Resmed Autoset II). After that during the trials I liked the Remstar Auto and therefore I purchased the new PR Series Remstar Auto. Now after 10 days of use my 90% Pressure shows 15.6 and I have complains of leaks from the mask(s). I have seen the pressure hits 19 - 20 when I have woken on several occasions to adjust the mask. There are a couple of questions which come to mind -

1. Does the seal of the mask deteriorate at the high pressures and what can be done to minimize the leaks. (I use a Ultra Mirage FF mask alongwith the one listed on my profile)

2. Does a Remstar operate differently from a Resmed - there is a 25% difference in the 90/95% pressure and 35+% in the maximum. (or alternatively my titration was not correct, I remember I didn't sleep well, it being my first time on a cpap)

I've seen a lot of post from very knowledgeable cpapers on this forum whose advise have been accurate and helpful and I am glad they are there and willing to help.

1. Yes, masks tend to leak more at higher pressures. It's a matter of physics. You need the mask tighter at higher pressures. Generally, you can also get away with less precise adjustment at lower pressures. You have to tweak more as the pressure goes up; AND there is less room for error between "tight enough" and "too tight". Too tight can cause leaks as well.

2. I can't explain the pressure difference. A 3cm difference suggests to me, also, that your titration wasn't a good sample. I would accept the results of 10 nights over ONE disturbed night (realistically, probably only a couple of hours...) every time.

Once you get your leaks under control and and some consistent numbers, you might want to try your machine in CPAP mode at your 90% pressure*. Several of us have found we get lower AHI doing that because the machine doesn't spend part of every night at the wrong pressure while searching for the right one.

*or APAP with both min and max set to your 90%. More data is reported in APAP...

What pressure range is your machine set to?

Without software (which isn't available), you don't have any idea what that PR Auto is doing while you're sleeping. Running an Auto CPAP in a range of pressures without software is a recipe for frustration. You either need to narrow your pressure range around your displayed numbers or switch to CPAP mode and tweak the pressure up or down according to the displayed results.
Unless, of course, you actually LIKE to be frustrated and confused about how your therapy is working.......


Den

Straying just a little in response, I have to say it's so hard to trust the results of the sleep study in terms of the "perfect" settings.

You're in a strange bed, covered with glue and wires, microphones near and far, and the beady eye of a camera watching every twitch. How can anybody pretend to sleep normally under those circumstances? Even at the height of my OSA, falling asleep at stop lights, I was only able to sleep for an hour and 40 minutes during my study.

I understand things are learned, but I don't think a perfect cpap setting is one of them. As hard as it might be for a new cpap user to get the mask leaks handled and create good data, my feeling is that a week or two of a reasonably wide auto range - while in your own bed - is needed to really see what the effective settings are.

I believe it's a process.

Wulfman wrote:What pressure range is your machine set to?

Without software (which isn't available), you don't have any idea what that PR Auto is doing while you're sleeping. Running an Auto CPAP in a range of pressures without software is a recipe for frustration. You either need to narrow your pressure range around your displayed numbers or switch to CPAP mode and tweak the pressure up or down according to the displayed results.
Unless, of course, you actually LIKE to be frustrated and confused about how your therapy is working.......


Den

Wulfman

Thanks, the APAP was set for a range of 8 to 20. Last night I just switched over to CPAP mode with the pressure set to 14. The results AHI was marginally better from 9.7 to 8.8 - I suppose will have to continue tweaking it over the next few days. However still had the frustrating problem of mask leaks (farts) waking me up.

Sham

shambharwani wrote:

Wulfman wrote:What pressure range is your machine set to?

Without software (which isn't available), you don't have any idea what that PR Auto is doing while you're sleeping. Running an Auto CPAP in a range of pressures without software is a recipe for frustration. You either need to narrow your pressure range around your displayed numbers or switch to CPAP mode and tweak the pressure up or down according to the displayed results.
Unless, of course, you actually LIKE to be frustrated and confused about how your therapy is working.......


Den

Wulfman

Thanks, the APAP was set for a range of 8 to 20. Last night I just switched over to CPAP mode with the pressure set to 14. The results AHI was marginally better from 9.7 to 8.8 - I suppose will have to continue tweaking it over the next few days. However still had the frustrating problem of mask leaks (farts) waking me up.

Sham

Good. At least with a constant setting, you can compare apples to apples. It's easier to try to narrow down whether the problem is leaks or the mask or pressure or just "what" you need to address. And, you'll probably sleep better without the pressure jumping all over the place.

Hang in there, you'll get it figured out. (maybe a different mask?)

Den