Mouth leak or mask leak.

[David Clark]

I don't visit all that often anymore...things are pretty much under control and at a level I can live with. I have seen people ask how to tell the difference in mouth leaks and mask leaks using OSCAR so I thought I would post this from last night so the group experts could distinguish which they are. Maybe it will help others looking for answers. 
It is kind of weird that I rarely have any leaks anymore. I'm using a Dreamwear FFM.

[multicast]

You can't have a mouth leak using an FFM per definitionem ... Either your mask has the wrong size or it's poorly adjusted.

Mike

[DaveL]

Thanks for posting. I hope to learn from future answers here

In the text you say you are using a Dreamwear FFM

On the left you say you are using an F&P Evora Full. I have that mask as well. Do you still use it? Or have you discarded it?

Reacting to your comment....I don't think that you have leakage under control. You have decent AHI; do you wake up rested and comfortable?

DaveL

[clownbell]

Yikes - with such a large percentage of time in Large Leak territory, gotta get a handle on it.

[manich]

When using a nasal mask, is the mask leak data, on ResMed's myAir app, including mouth leaks?

[cathyf]

When using a nasal mask, is the mask leak data, on ResMed's myAir app, including mouth leaks?

My experience is that if you use a nasal mask and you inhale through your mouth (bypassing the cpap-airway system) and exhale out your nose (into the nasal mask) then a ResMed machine completely loses its mind.

It reports the flow rate curve that it sees -- which is regular breathing with the same number of breaths per minute, with clear obvious peaks and valleys. At the same rate as before, just not as much air going through the nose. When the inspiratory peaks don't make it to 4 the the machine stops seeing these as the breaths that they clearly are and it logs the respiration rate as zero.

Here's a 3-minute slice:

I zoomed in very closely on the flow rate (+8 to -8) and put the respiration rate right under. When the inspiratory peaks don't make it to 4 (actually like 4.1) then the respiratory rate gets reported as zero, even though it's obviously the same 9-1/2 or so as before.

After 1-1/2 continuous minutes where the inspiratory flow rate doesn't make it above 4, the machine turns itself off. See this 12-minute view, which has some overlap with the other view:

All of the recording just stops for 8-1/2 minutes. Apparently the machine just turns itself off, and doesn't come back on until the arousal (which it scores as a RERA.) The machine shuts off running a pressure of 12.96 and comes back at the RERA with the pressure setting at the exact same 12.96 -- totally different behavior than a shut off, where it comes back on at the minimum (I run my machine at 7-20.)

Note that at no time during this period is the leak recorded as being even close to red line.

As far as MyAir is concerned, nothing happened. The machine recorded itself becoming completely confused because the algorithm doesn't recognize the sensor readings as "breathing". The machine's response to thinking that I wasn't breathing was to turn itself off for 8-1/2 minutes -- freaking EIGHT AND A HALF FREAKING MINUTES!!!!! This is a machine whose ONE JOB is treating sleep apnea, and it is programmed to turn itself off when it can't figure out if I'm breathing. I was sleeping with a pulse oximeter, and oxygen was fine, so obviously I was breathing through my mouth and getting plenty of air. But the machine recorded itself not knowing what was going on.

This is a machine which phones the ResMed servers every day and reports what happened. It recorded itself in a state of complete confusion, but it reported that everything was fine, no reason to be concerned.

I've seen enough of ResMed machines with nasal masks. They don't work if you breathe through your mouth.

[pholynyk]

The MyAir data on leakage is based on the total unintentional leakage.

The machine, and therefore MyAir, has no way to determine the cause of the leaks.

We humans make our guess based on looking at the leakage graph - which, for ResMed machines, is the unintentional leakage.