What is the difference between large leak and leak rate?

[ILoveFlowers]

Looking at Oscar, there is a graph for 'leak rate' and then there is a listing on the left side for 'large leak'. Can someone explain the meaning of these two? Thank you!

[ChicagoGranny]

Looking at Oscar, there is a graph for 'leak rate' and then there is a listing on the left side for 'large leak'. Can someone explain the meaning of these two? Thank you!

Large leak is larger than leak. You're welcome.

Look at your leak line on the graph. There will be a straight red line. Any leak above the line is considered ... wait for it ... large leak. Any leak below the line is considered within the normal leak range for which the machine can compensate.

With my machine and mask, the red leak line is at 28 liters per minute. In my experience, my machine will compensate for leak up to 35 to 38 lpm.

You are smart to be questioning this and observing it. If your leak is too high, it's a good idea to readjust your mask.

[Pugsy]

All machines will leak...either intentional (vent rate) leak or excess leak (above vent rate) or combination of both.

They may or may not report the leak a bit differently. ResMed reports excess leak only (compared to Respironics and some others that report both vent rate leak and any excess leak).

You have a ResMed machine. It reports excess leak only. Now it can compensate quite nicely for some excess leak but ResMed says that the 24 L/min leak line is its line in the sand where any leak above 24 L/min is considered a "large leak" and it alerts to potential large leak big enough to negatively impact the therapy itself. 5 minutes in large leak is a lot different than 50 minutes of large leak.
Now IMHO that 24 L/min line is ultra conservative. I haven't seen any real impact from a "large leak" until I hit 30 to 35 L/min leak.
Above that an all bets are off and if we notice large leaks the machine could have trouble sensing and responding and recording.

Me personally......as long as the leaks aren't waking me up and I am not spending much time over 30/35 L/min I don't worry about the leaks. That 5 minute large leak vs 50 minute large leak. So it is important just how deep into large leak territory that you go and how long you stay there.

[ChicagoGranny]

ResMed says that the 24 L/min leak line is its line in the sand where any leak above 24 L/min is considered a "large leak"

Since you said that, I looked again, more closely this time. My red line is probably at 24 instead of the 28 in my previous post.

[Pugsy]

ResMed says that the 24 L/min leak line is its line in the sand where any leak above 24 L/min is considered a "large leak"

Since you said that, I looked again, more closely this time. My red line is probably at 24 instead of the 28 in my previous post.

OSCAR defaults to using the ResMed 24 L/min large leak red line but it plays hell with reports from other brands when computing percent of time in large leak as well as graying out the leak bars to highlight large leak. Remember Respironics users all in a panic because OSCAR said that their leaks were MASSIVE??? When in reality that 45 L/min leak line is/was actually either no leak to speak of or any leak line movement went along with any pressure changes. Then a ResMed user comes along and tells the Respironics user that their leaks are massive (and they aren't) and scare the bejesus out of someone and cause them to work hard to fix a leak problem that they don't have.

At any rate that 24 L/min line is just a default and it can be changed if someone wishes. I quite often just set it to 30 L/min and then worry about time in large leak.

I don't even blink an eyelash until the leak line goes over 30 L/min and stays up there for half an hour or more (assuming I am sleeping through the leaks).