Help with question about how leaks are calculated

Country4ever · Post by **Country4ever** » Thu Jul 10, 2008 6:17 pm

Hi all,
Question: I use the original Swift nasal pillow and have a ResMed Auto Vantage machine. Do the leaks through the mouth show up on the leak data in the morning, or is it just the leaks around the nasal pillow?
Thanks.

RiverDave · Post by **RiverDave** » Thu Jul 10, 2008 8:13 pm

I'm pretty sure it reports all air escaping minus the vent flow rate for the mask as leaks. I don't think it can differentiate between air escaping the mask or your mouth. Seems like there would have to be some kind of measurement taken at the mask to determine this, and since there is no sensor in the mask...

But, I've been wrong more than I've been right.

Babette · Post by **Babette** » Thu Jul 10, 2008 8:25 pm

RiverDave wrote: But, I've been wrong more than I've been right.

Does this mean you're not a NATIVE of Texas?

Better run before I "Dixie Chick" myself...

LOL,
Babs

RiverDave · Post by **RiverDave** » Thu Jul 10, 2008 8:32 pm

Babette wrote: Does this mean you're not a NATIVE of Texas?

Better run before I "Dixie Chick" myself...

LOL,
Babs

As the bumper sticker says

"I wasn't born in Texas, but I got here as fast as I could"

dsm · Post by **dsm** » Fri Jul 11, 2008 7:27 pm

[quote="Country4ever"]Hi all,
Question: I use the original Swift nasal pillow and have a ResMed Auto Vantage machine. Do the leaks through the mouth show up on the leak data in the morning, or is it just the leaks around the nasal pillow?
Thanks.

Country4ever · Post by **Country4ever** » Sat Jul 12, 2008 9:33 am

Thanks Dave and DSM.

echo · Post by **echo** » Sun Jul 13, 2008 6:24 am

So we still don't have a definintive answer....

are mouth leaks detected by our machines or not?
if not, why not?

bap40 · Post by **bap40** » Sun Jul 13, 2008 7:59 am

I have been under the impression that mouth leaks are just calculated the same as mask leaks and all totaled together.

echo · Post by **echo** » Sun Jul 13, 2008 5:36 pm

I've heard (on this forum) that mouth leaks can't be detected by the machine - but I forget who said it??

Snoredog, ozij, RG, ... anyone, anyone???

feeling_better · Post by **feeling_better** » Sun Jul 13, 2008 8:32 pm

I am pretty sure all machines first measure the total airflow out of the machine, and then some of the machines subtract the 'fixed intended leak' amount set into the machine or looked up for a known mask which is set into the machine. The air flowing out the mouth is same as any other unwanted leak for the total air flow measurement.

Here is a recent thread on how to measure for yourself the exact leak for your mask and machine combination. Those machine types which subtracts the leak and reports the true unwanted leak, would give a value close to 0 when using the method below. For the other type, such as Respironics M-series, it will give the a value close to the manufacturers published leak rate for the pressure setting during the experiment.

viewtopic.php?t=32896&highlight=

Machine	Mask

Additional Comments: Resmed HumidAir 11 for humidifier

Help with question about how leaks are calculated

Help with question about how leaks are calculated

Re: Help with question about how leaks are calculated