2 masks--2 different sets of data

M'ohms wrote:

Morbius wrote:OK, busy watching for the Revealing of the Easel, but Flushier = More CO2 Washout and explain the difference in breathing pattern.

This is where my eyes glaze over. I have read about this any number of times, but I don't understand it. Can you explain this principle to this thick-skulled ninny?

as I understand it, the co2 in your blood is what drives the breathing cycle, if your co2 is low, then you don't have the drive to breath, so you may not initiate a breath on your own, and the asv says "NO! you need to breath!" and that reduces your patient initiated breaths on the report.

looking forward to any corrections about any misunderstandings I have on this point.

With Fitlife you ADD more dead space. With Quattro, not only is mechanical dead space flushed, but if you have your mouth open, much of the anatomical dead space is flushed as well (oral > nasal > vent).

Thanks PR and Morbius for the explanation. OK, so let me see if I got it...

With the FitLife, I have a larger dead space and relatively smaller vent, and this translates into my brain saying,"You've got CO2 in your body--breathe so that it can be expelled". So I breathe on my own, which is deeper and more regular, and this translates into higher Tidal Volume and higher Patient Triggered Breaths.

With the QFX, I have a smaller dead space and relatively larger vent, which evacuates more CO2. My brain says, "You don't need to breathe because there is no CO2 to get rid of". And like PR said, my ASV says "You haven't breathed in a while so breathe now!" . This translates into more machine triggered breaths (lower PTBs), which my brain still isn't convinced is necessary so I don't breathe deeply or as frequently. This results in lower TV and lower PTBs.

Does this sound about right?

M'ohms wrote:Thanks PR and Morbius for the explanation. OK, so let me see if I got it...

With the FitLife, I have a larger dead space and relatively smaller vent, and this translates into my brain saying,"You've got CO2 in your body--breathe so that it can be expelled". So I breathe on my own, which is deeper and more regular, and this translates into higher Tidal Volume and higher Patient Triggered Breaths.

With the QFX, I have a smaller dead space and relatively larger vent, which evacuates more CO2. My brain says, "You don't need to breathe because there is no CO2 to get rid of". And like PR said, my ASV says "You haven't breathed in a while so breathe now!" . This translates into more machine triggered breaths (lower PTBs), which my brain still isn't convinced is necessary so I don't breathe deeply or as frequently. This results in lower TV and lower PTBs.

Does this sound about right?

as I understand it, you're pretty much dead on....

machine triggered breaths are also going to give you a lower tidal volume and minute vent, because while they do ventilate you, they don't do it as well as normal breathing, .. with the resmed asv, I think they target 90% of whatever your current ventilation rate is... so your tv and mv will drop when the machine is doing the work.... so, that fits in with what you said too

Once again, PR, you have helped me! Thanks for your imput!

Also it's the LOCATION of the vent on Quattro. It purges the mask air, and if your mouth is open, it purges the oro-nasopharyx, so the deadspace is even lower than what it would be without the mask.

M'ohms wrote:Once again, PR, you have helped me! Thanks for your imput!

hopefully I'm at least in the ballpark, I would have expected a slap upside the head from Morbius if I weren't

Morbius wrote:Also it's the LOCATION of the vent on Quattro. It purges the mask air, and if your mouth is open, it purges the oro-nasopharyx, so the deadspace is even lower than what it would be without the mask.

Thanks, Morbius. What you said makes sense to me. In your opinion, am I better off using the FitLife since the TV and PTBs are more favorable than with the QFX, or does it matter?

Theoretically, the Quattro design could generate/worsen central apnea chains, CSR, and PB. If that is not occurring, then I do not believe there is an issue.

I'm not having problems like that, so I will continue to make the QFX my go-to mask. Thanks again for your time and expertise!