Experiment: FFM + Mouth Tape

[brain_cloud]

The data seems to show that the Mirage Activa nosebag is giving you better results; why go to full face mask and try to improve things?

Dude, it's for SCIENCE! I can't put my own selfish therapy needs above SCIENCE. The ghost of Carl Sagan would rattle his chains at me. Mankind is my business.

[SleepingUgly]

SU, I'm sure that is how this will play out. Yes, I have a solution. But I'd also like closure on this FFM+tape=NM+tape issue. .

OK, then you need more data points than just those three. Keep wearing the FFM and taping. But do you have another FFM besides that one that you could do it with after several more nights with the Quattro?

[brain_cloud]

SU, I'm sure that is how this will play out. Yes, I have a solution. But I'd also like closure on this FFM+tape=NM+tape issue. .

OK, then you need more data points than just those three. Keep wearing the FFM and taping. But do you have another FFM besides that one that you could do it with after several more nights with the Quattro?

Nope, the Quattro is going to have to be the exemplar of Full-Face-Maskiness and stand in for all his (its?) kind.

Poor SU, up so late. I must to-bed mine ownself.

[DreamStalker]

Leak info is as follows: Leak is negligible when using the Quattro, with and without tape. Leak with the Activa happens, but not on a scale to cast the data into doubt. Leak is not a factor here.

Obviously, you are not supposed to need tape or any other artifice to ensure mouth closing when using a FFM. In theory, theory and practice agree; in practice, they don't.

I think your assumption about the leak significance is misunderstood ... especially if you are doing this science project in APAP mode.

The pressure and flow sensors used to both score events and input into the auto algorithm are quite sensitive to leak characteristics. The volume of the of the interface relative to the volume of your own respiratory system affects the transient response of both flow and pressure back to the machine's sensors as does the leak flow rate(s). Each mask has a somewhat unique CO2 vent flow rate and variability of this flow exists even under ideal conditions for the same model mask and more so between different mask types.

For example, when the Hybrid first came out, the initial version had a very high CO2 vent flow rate. Many who first trialed this mask were having issues with great increases in the event scoring despite maintaining a good mask seal. It turned out that most of the problems were associated with people using APAP mode. The manufacturer had to revise the mask and lower the CO2 vent flow rate in order for it to work properly with APAP machines.

If you want to reduce the effects of leaks on your science project, I would recommend that you do your experiment under normal continuous CPAP mode as opposed to APAP mode (assuming that you are conducting your project in APAP mode). Either that or plot the leak variability (as max - min or standard deviation ... not just average or max).

Just saying.

[Jaylee]

Poor SU, up so late. I must to-bed mine ownself.

Do you see this, UggyPooh? He only talks like this because he knows it makes me crazy.

[SleepingUgly]

Poor SU, up so late. I must to-bed mine ownself.

Do you see this, UggyPooh? He only talks like this because he knows it makes me crazy.

You like this combination of Shakespeare + Yoda, huh?

[brain_cloud]

I was on the point of advising that cpaptoronto guy that to pitch woo in Jaylee's direction, he ought to try love poetry.

Not that the story about the time he almost died, etc., etc., isn't compelling.

[brain_cloud]

Leak info is as follows: Leak is negligible when using the Quattro, with and without tape. Leak with the Activa happens, but not on a scale to cast the data into doubt. Leak is not a factor here.

Obviously, you are not supposed to need tape or any other artifice to ensure mouth closing when using a FFM. In theory, theory and practice agree; in practice, they don't.

I think your assumption about the leak significance is misunderstood ... especially if you are doing this science project in APAP mode.

The pressure and flow sensors used to both score events and input into the auto algorithm are quite sensitive to leak characteristics. The volume of the of the interface relative to the volume of your own respiratory system affects the transient response of both flow and pressure back to the machine's sensors as does the leak flow rate(s). Each mask has a somewhat unique CO2 vent flow rate and variability of this flow exists even under ideal conditions for the same model mask and more so between different mask types.

For example, when the Hybrid first came out, the initial version had a very high CO2 vent flow rate. Many who first trialed this mask were having issues with great increases in the event scoring despite maintaining a good mask seal. It turned out that most of the problems were associated with people using APAP mode. The manufacturer had to revise the mask and lower the CO2 vent flow rate in order for it to work properly with APAP machines.

If you want to reduce the effects of leaks on your science project, I would recommend that you do your experiment under normal continuous CPAP mode as opposed to APAP mode (assuming that you are conducting your project in APAP mode). Either that or plot the leak variability (as max - min or standard deviation ... not just average or max).

Just saying.

Almost all of the data above was collected while using my S9 in CPAP mode at 19. A few of the days, it was in APAP mode with tight window (18.4-20.0).

Leak with the Quattro is essentially nonexistent. That is one the main reasons I would prefer it that the Quattro+tape (or perhaps a mouthpiece) be equivalent to the Activa. I get a fantabulous seal with the Quattro.

I recently got a Swift FX (nasal pillows system) and a hybrid mask as well. So I'll be checking those out as well.

[Jaylee]

Poor SU, up so late. I must to-bed mine ownself.

Do you see this, UggyPooh? He only talks like this because he knows it makes me crazy.

You like this combination of Shakespeare + Yoda, huh?

Hey, I never said I wasn't weird, Uggy. You know that better than anyone else here.

[jdm2857]

I too am at a loss for an explanation, but the data is consistent and overwhelming.
Data refusing to fit our expectations does not disqualify its validity;
it may disqualify the universal applicability of our hypotheses.

Velbor

No argument with that statement. The theories must fit the data, and not vice versa.

And I, too, am confounded.

Maybe a research project using the real-time x-ray device mentioned elsewhere would be appropriate.

[brain_cloud]

I too am at a loss for an explanation, but the data is consistent and overwhelming.
Data refusing to fit our expectations does not disqualify its validity;
it may disqualify the universal applicability of our hypotheses.

Velbor

No argument with that statement. The theories must fit the data, and not vice versa.

And I, too, am confounded.

Maybe a research project using the real-time x-ray device mentioned elsewhere would be appropriate.

OK, I'll start searching craigslist for a used x-ray machine; you start screening test subjects. No hippees.

Besides SU's open-mouth hypothesis, another possible explanation is that with a FFM like the Quattro, the bottom portion of the mask together with the bottom strap of the headgear, are pushing the lower jaw in the worst possible direction.

[SleepingUgly]

another possible explanation is that with a FFM like the Quattro, the bottom portion of the mask together with the bottom strap of the headgear, are pushing the lower jaw in the worst possible direction.

That's why I asked if you have another FFM. We need to distinguish between FULL FACE MASK effects and QUATTRO effects (on YOU). Unless you could get someone else to do your experiment elsewhere, so far this study only generalizes to you.

[Velbor]

....The pressure and flow sensors used to both score events and input into the auto algorithm are quite sensitive to leak characteristics. The volume of the of the interface relative to the volume of your own respiratory system affects the transient response of both flow and pressure back to the machine's sensors as does the leak flow rate(s). ....

While leak is commonly blamed for much that we don't like or that we can't explain, what little information the manufacturers do provide does not support the "quite sensitive" characterization. See:

viewtopic.php?f=1&t=41964
Leak: What the Manufacturers Say

Further to the issue, while our typical respiratory airflow of 5 lpm (est. 500cc / breath x 10 breaths/min) is indeed small compared to typical mask venting flow of 35 lpm (e.g. 31 - 37 lpm @ 10cm for ResMed masks per
http://www.resmed.com/us/assets/documen ... sa_eng.pdf ), venting rates of 48 lpm or more are expected with some masks (at higher pressures), and typical "acceptable" leak rates of 24 lpm or less ADDED TO the venting are well within machine capabilities and thus can contribute 1/3 of the total airflow our machines are designed to handle routinely. Again, this does not suggest "sensitivity" of sensors to leak.

I would caution that we be very careful what nasties we attribute to leak. Velbor

[brain_cloud]

another possible explanation is that with a FFM like the Quattro, the bottom portion of the mask together with the bottom strap of the headgear, are pushing the lower jaw in the worst possible direction.

That's why I asked if you have another FFM. We need to distinguish between FULL FACE MASK effects and QUATTRO effects (on YOU). Unless you could get someone else to do your experiment elsewhere, so far this study only generalizes to you.

In that case, you may address me as Generalissimo Cloudy. I am the very model of a a modern CPAP general.

[Jaylee]

Cloudy, do you have, like, eight children? You strike me as the kind of man who would have eight children.