[CPAP] New to full-face mask, getting a pressure bounce on exhalation

[glomph]

Background - have used ResMed machines for about a decade, current one is an almost-new AirSense 10.

Have always used nasal pillows, but constrictions of nasal passages have made this a poor experience of late.

Just got an AirTouch F20 mask- the fit is fine,  no problem there.    Set Mask Type to Full Face on the machine.

I had to reduce the Minimum pressure substantially,  with my previous setting of 12, the thing just about blew off my face.

Now down to the 8 range,  and that seems about right.  Probably.    Using the standard heated hose.

BUT---

On exhalations,  about ⅔ of the way out,  there's a small bounce in mask-to-face pressure, which is pretty annoying.

Have tried EPR off,  and on at different levels.   Makes little difference.  (with nasal pillows i used EPR on/level 1)

Any way to eliminate this perceived pressure bounce?  It's not great for sleep.

(off-topic) the mask woooosh is MUCH louder than that of the nasal pillows.

-----
Thanks for reading, and for any insights - I did search the forum first!

Happy Holiday Season,
Dr Glomph

[SarcasticDave94]

Members would need to see the OSCAR charts to help figure out the pattern.

On the mask, unfortunately, if you are forced to lower therapy pressures to accommodate a mask, then the mask isn't compatible for you. You'll likely need to choose something else.

While on ASV in 2017-19, I tried to get the ResMed F20 mask to work. Tried for almost a year with both silicone and memory foam. I should have moved on within 3 months to avoid extra frustration. If this mask is a hindrance to therapy, swap in a different one that doesn't require restricted therapy settings.

[glomph]

Thanks for the reply, much appreciated - I'll get some OSCAR data out of this after a few nights.

About the pressure setting:  I have long been having tremendous trouble, not with mucus congestion, but with very constricted turbinates (lining of upper nasal passage) as well as a deviated septum.    I think the main reason the pressure setting is so different is that there is a huge pressure-drop across my nasal passage constriction.

As a backup I have a new P30i,  my long-standing mask default.

A bit surprising, maybe: The vents (the "gable window frames" just downstream of the rotating hose connector = see photo) on the F20 seem to be really, really large compared to the little array-of-pinholes on the various nasal pillow masks I've used.   Perhaps this is due to the much greater dead space relative that of the little nasal pillows.   The pinholes on the pillow masks tend to clog with ambient room dust (looks like black soot) after a short period of use.

The cervical collar suggestion makes a  lot of sense - I've ordered one - thanks for that.

[SarcasticDave94]

Yes, I've seen the black dots in the vent elbow myself.

There's a discussion on the Board somewhere. If I find it, I'll post the link.

I think it was within the new at the time Quiet Air elbow chat. I removed the white packing when the dots appeared. No more quiet elbow but no more dots as well.

Here's the one I was thinking of. Use search for others.

https://www.apneaboard.com/forums/Thread...+Air+elbow

[glomph]

With care I've been able to fish out those little filter pads and wash/return them to their original locations.

[SeePak]

glomph

"I had to reduce the Minimum pressure substantially,  with my previous setting of 12, the thing just about blew off my face."....

Your bio says you use a pressure range of 10 to 20 cm

Even though you set the minimum pressure lower, the machine will go to much higher pressures than that thru the night?!
So the mask will or should still "blow off your face" if it was a pressure problem that caused it.

Does it?

[glomph]

I've resolved most of the problems, other than just getting used to a full-face mask after a decade of nasal pillow use.  That will take some time, or maybe I'll eventually return to the pillows.  Definitely more inconvenient to put on, etc.

Not sure what that "blow off the face" event was during my out-of-the-box trial.   That was quite odd.   My guess is that it was a really horrible leaky fit, and the machine was blasting air into it.    Has not recurred.

APAP Min/Max and EPR setting are back in the general vicinity of where they were with the pillow masks.  (10-15-3).   Will be doing some titration over the next few nights, checking out the OSCAR graphs.   First night had really poor sleep for reasons unrelated to CPAP.

The 'bounce' was due to WAY unnatural breathing (deep rapid forced exhalation) not typical of relaxed sleeping, which I think was overdriving those flapper gates covering the vents.    Does not occur in normal use.   Overall whooosh noise a bit above the nasal pillow level, but not horrible.