tan wrote:So the cloth is not a pressure equalizer but a valve since there is no external pressure, which may work for the author as it does for you. I have tried different methods of tape covering with P10
Yes, I am the "author". I came up with this to help a friend who "had" to tape because of mouth leaks, but "had" to quit due to skin irritation. To see if it would work, I tried it on myself first. It worked so well, I have continued to use it.
For years I have worn a FFM because of mouth leaks. About a year ago, I had to switch to a Nasal Mask due to a nerve problem caused by the headgear of a FFM. Anyway, over some months, my mouth leaks became more tolerable but still somewhat disturbing. In the past, I have used chin straps, tape, cervical collars, etc. to improve therapy, so I am familiar. Here's the bottom line: With this setup; A P10 and cloth mouth cover, my results are better than they have ever been with any other combination of mask and equipment. The nasal mask requires a lower pressure than a FFM to suppress obstructive events and my Flow limitations are nearly non existent. My best Flow Limitation reduction in the past came with using a soft cervical collar. I no longer use one and my FL are better.
Yes, the cloth works somewhat like a valve allowing air out easier than in and it muffles the sound and feel of air exiting so well that I can't actually tell when it is occurring. The blowfish effect doesn't happen with the cloth because pressurized air is allowed to naturally escape through the lips without sound or feel. That is not to say that these "leaks" don't register with SleepyHead, they do, but are rarely over 24 L/min and are not disturbing. My average (not median) leak has dropped from around 12L/m to 5L/m, the median is 0. I think the cloth works similarly here as in cloth mask liners which, I believe, make mask leaks tolerable but don't prevent them.
The hairbands I've been using won't prevent chin drop, but they are wide and stretchy enough to cover the mouth when full open. I think they do discourage chin drop in that there is a small (maybe a 1/2 inch wide) elastic band inside the headband at one edge such that when this internal band is down, it provides a slight upward lift to the lower lip tending to keep it closed. Overall, these bands exert very little pressure on the mouth and their effect results more from just being in place rather than providing any pressure to keep something closed.
Additionally, the cloth is not restrictive to mouth motion so one can swallow, exhale, move the tongue around, etc., much more naturally than with tape and therefore, it is less disturbing. Also, the cloth will allow an exhale through the mouth when it is a natural response to do so.
I consider these hairbands (headbands) to be one of the best devices for improving CPAP therapy that I've used over the past 10 years, or so, that I've been fooling with this stuff and I've tried a bunch.
