Having difficulty exhaling into full face mask

[2Tim215]

I hope Esoteric comes back so we can help, are you out here Esoteric? More information will probably help you sleep better tonight. Hope to hear from you soon, don't ever give up on your therapy!

[Shastzi]

For a while I was using a Respironics Spectrum mask which is similar. It did not work well at all with low pressures. The feeling of rebreathing stale air was opressive. At higher pressures it began to ventilate better though. I am thinking the design may have a problem with dead space in the mask. ie: not enough air turnover occurs at lower pressures.
***
Also be advised that the RemStar Plus is a dumb machine only a bit smarter than a hair dryer.
When you select a pressure of 4cm on the front panel, you are just setting a motor speed control and not a real pressure setting. If you measure the actual pressure in the tube while wearing the mask it can vary a good bit depending on how large the exhaust vents are on the mask.
Unless you set the pressure with a manometer connected you never know what you are really getting from the machine.

[archangle]

Also be advised that the RemStar Plus is a dumb machine only a bit smarter than a hair dryer.
When you select a pressure of 4cm on the front panel, you are just setting a motor speed control and not a real pressure setting. If you measure the actual pressure in the tube while wearing the mask it can vary a good bit depending on how large the exhaust vents are on the mask.

I don't believe that's correct. I think even the dumbest CPAP machines have some sort of pressure sensing to maintain a fairly constant pressure as long as you don't have excessive leaks besides the exhaust vent.

[Shastzi]

I don't believe that's correct. I think even the dumbest CPAP machines have some sort of pressure sensing to maintain a fairly constant pressure as long as you don't have excessive leaks besides the exhaust vent.
[/quote]

I'm afraid so, in the case of the REMstar Plus.
I took the pressure measurements myself on the REMstar Plus with a digital manometer and it really can be way off, such that I have to bump the setting up or down depending on which mask and hose gets used with it. Some of the newer (and more expensive) machines however do have a pressure feedback loop built in to do this, specially the 'Auto' machines.
So..what you see ain't always what you get...
So I can only conclude that the REMstar Plus does have a really fancy motorspeed control but thats about it.
I'm working on some pressure differential / rate of leak calculations today just to see how *bad* it can get with different masks in my collection.

I have a camera too & can post pictures.
Cheers!

[SuperSleeper]

So I can only conclude that the REMstar Plus does have a really fancy motorspeed control but thats about it.

Hi Shastzi,

If a manometer shows a slightly different pressure than that which your REMstar Plus is set at, it does not necessary mean that the only thing regulating the REMstar's pressure is simply a "fancy motor speed control". It could mean that that the actual pressure-sensing device is malfunctioning, or there is a small internal hose leak affecting delivered pressure, or that it was not set properly at the factory.

I would also ask what model of REMstar Plus you're using? If it's an older pre-2007 version, or even an "M Series"... well, 5 years is the useful life of most CPAP machines and I would not expect to have a flawlessly operating CPAP machine after that 5 year period.

Here's the various models of REMstar Plus machines:

[zonk]

PRS1 plus is exactly the same machine as PRS1 Pro minus efficacy data, system one resistance and the altitude compensation is manual

http://www.healthcare.philips.com/asset....-guide.pdf

[archangle]

PRS1 plus is exactly the same machine as PRS1 Pro minus efficacy data, system one resistance and the altitude compensation is manual

http://www.healthcare.philips.com/asset....-guide.pdf

The Pro also shows leaks, which the Plus doesn't.

The PRS1 Pro has an airflow sensor and a pressure sensor. The Plus only has an airflow sensor.

At one time, there were only two different PRS1 hardware designs. DS150 and Plus were one set of hardware. Pro, Auto, and all the BiPAPs were all the same hardware design with different software and labeling.

Now there is 50 series and 60 series. My "inside information" is a few years old, so it's possible that some of the newer machines have a different hardware design, but I'd bet that there are really only two different hardware designs for all the 60 series as well.

[zonk]

archangle ... are you one of those in this picture

[idahocouchpotato]

I had difficulty exhaling with my Mirage Quattro mask at 16 cm for the first two weeks. I guess the muscles I use to breathe were just out of shape because by week number 3 I had no trouble exhaling anymore. Maybe the OP should just stick it out for a few more nights after verifying that his equipment isn't faulty or improperly set up. It's amazing what our bodies can adjust to with enough time and patience.

[Shastzi]

Thanks SuperSleeper!
I have the pre-2007 model that I picked up about '02' and it has been carefully stored most of that time.
I was running at 12.5 cm (measured) H2O and still showing a few annoying desats. So I set the front panel last night to 12cm and the manometer was showing 13.9-14.0cm.
(note: for this mask the machine delivers more than you bargained for! So I dont think there are any internal leaks. If I put a different mask on it with larger calibrated leak factor the pressure drops..A LOT.
So I dont think this particular machine has any real pressure feedback loop directing an auto servo motor speed control. It
is after all "a brick" )
Cleaned up the mask and got a good seal and decent sleep. (If only the cats wake my up, I call it good.)
Morning oximeter report show no drops below 91% O2.
No sinus issues, got a bit of dry mouth and eye irritation but no big deals.
This is good.
=^.^=