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Wulfman... wrote: There is no "intentional" or "unintentional" leakage reported in the Encore programs.
The Encore programs report TOTAL leak........Average and Large.

Yes there is. It's a preference toggle. See the screenshot below.

Thanks for the correction Brian.

Now I know there are other reasons why I'm not going to upgrade from the versions I'm currently using.


Den

Sorry I meant Doug... please post the graphs/data in question.

Knowing there is a setting for leaks (intentional vs unintentional) but there is NO setting for the mask (the variable)- I wonder if this is a flat rate conversion done in the software?

Doug, I'm assuming that you found your problem. Was it this leak setting?

GumbyCT wrote:Knowing there is a setting for leaks (intentional vs unintentional) but there is NO setting for the mask (the variable)- I wonder if this is a flat rate conversion done in the software?

I was wondering this also.

To get a better sense of it I would have to use straight cpap mode because with the variation in APAP there for sure seems to be a variable with the base line. I have seen from 25 to 30 difference when I toggled between Unintentional leak and Total leak. A variable then would be my pressure fluctuations. Also wondering if the baseline happens to be different for different masks (even though we don't choose a mask type) for this I would also need another mask type and I don't have one. Wondering if the baseline or flat rate conversion is figured or started when we first turn on the machine and shouldn't have any leaks?

I will look back on some of my reports and see if I can find a few that the pressure doesn't ever rise except for the probes.
Then I can toggle back and forth to see if baseline is more constant. I can also try straight cpap to see what happens.
Maybe someone with different mask (as in full face since those masks typically have a larger vent rate) could compare.

I would have liked to have seen the 2 graphs that Doug saw with EP Total and Unintentional leak lines along with pressures. Just to make sure nothing else was a possible variable. It is also possible that even though his vent rate was say 45 (I don't remember) that the machine doesn't use that exact number as the base. He would need to toggle back and forth between a few nights and subtract the numbers to arrive at baseline. Maybe a generic baseline number is used. Maybe 25 or 30 is used. That could account for the difference in reporting.

Pugsy wrote:I would have liked to have seen the 2 graphs that Doug saw with EP Total and Unintentional leak lines along with pressures. Just to make sure nothing else was a possible variable.

Ha, I tried twice....good luck with that.

Now I have a sneakin suspicion they were different sleep sessions compared in different software.

Okay, I experimented and tried to come up with a general "baseline" that Encore Pro uses when it figures leak rate.
Using Swift FX nasal pillows APAP mode I have 3 recent nights with very minimal pressure increases which were essentially the probes.
Minimum pressure set at 10 cm. At this pressure the paperwork with mask says unintentional leak/vent rate is 33 L/min.
Mask resistance setting at 0 just in case this makes any difference, though from what I have read, it shouldn't.

Baseline unintentional leak number seems to vary slightly but very close. Using Encore Pro and toggling between Total Leak and Unintentional Leak reports I get these numbers. Encore Viewer total leak report matched Total Leak in EncorePro

May 24 Avg pressure 10.1cm Unintentional Leak reported 1.3 L/min Total Leak reported 26.0 Difference is 24.7 L/min
May 25 Avg pressure 10.3cm Unintentional Leak reported 0.5 L/min Total Leak reported 25.0 Difference is 24.5 L/min
May 27 Avg Pressure 10.2cm Unintentional Leak reported 0.9 L/min Total Leak reported 27.0 Difference is 26.1 L/min

Difference being roughly the vent rate allowed.
Obviously these "baseline" unintentional leak/vent numbers are well below what the mask literature states.

Could someone else using a different mask and/or at different pressures do this same experiment to see what their baseline difference is? I am wondering if it is the same number or close like I got or if the number seems to be different for other users.

Straight CPAP has the least pressure variable but APAP with essentially no increases will also work.
It isn't rocket science and I am not worried about minute differences, just looking for general idea if this baseline varies from mask to mask or even pressure to pressure.

Pugsy wrote:Okay, I experimented and tried to come up with a general "baseline" that Encore Pro uses when it figures leak rate.
Using Swift FX nasal pillows APAP mode I have 3 recent nights with very minimal pressure increases which were essentially the probes.
Minimum pressure set at 10 cm. At this pressure the paperwork with mask says unintentional leak/vent rate is 33 L/min.
Mask resistance setting at 0 just in case this makes any difference, though from what I have read, it shouldn't.

Baseline unintentional leak number seems to vary slightly but very close. Using Encore Pro and toggling between Total Leak and Unintentional Leak reports I get these numbers. Encore Viewer total leak report matched Total Leak in EncorePro

May 24 Avg pressure 10.1cm Unintentional Leak reported 1.3 L/min Total Leak reported 26.0 Difference is 24.7 L/min
May 25 Avg pressure 10.3cm Unintentional Leak reported 0.5 L/min Total Leak reported 25.0 Difference is 24.5 L/min
May 27 Avg Pressure 10.2cm Unintentional Leak reported 0.9 L/min Total Leak reported 27.0 Difference is 26.1 L/min

Difference being roughly the vent rate allowed.
Obviously these "baseline" unintentional leak/vent numbers are well below what the mask literature states.

Could someone else using a different mask and/or at different pressures do this same experiment to see what their baseline difference is? I am wondering if it is the same number or close like I got or if the number seems to be different for other users.

Straight CPAP has the least pressure variable but APAP with essentially no increases will also work.
It isn't rocket science and I am not worried about minute differences, just looking for general idea if this baseline varies from mask to mask or even pressure to pressure.

I decided to stick with total leak but here is what I get for the past few nights

Avg pressure 10.7 with a Total Leak of 43.1 with an unintended leak of 15.4 a difference of 27.7
Avg pressure of 10.7 with a Total Leak of 38.1 with an unintended leak of 10.4 a difference of 27.7
Avg pressure of 11 with a Total Leak of 38.2 with an unintended leak of 10 a difference of 28.2
Avg pressure of 10.4 with a leak of 39.1 with an unintended leak of 11.7 a difference of 27.7

At a pressure of 10 my mask should have a leak of around 38, not 27.7. The baseline is clearly incorrect.

DougVK wrote:At a pressure of 10 my mask should have a leak of around 38, not 27.7. The baseline is clearly incorrect.

Those differences seem to coincide with mine and pretty much the pressure I use.
So that was with Doug's Full Face mask.
Anyone who uses a higher pressure could you also check to see what the difference is?

With no mask feature selection I am not surprised that the baseline is not spot on for any of us. I am wondering if higher pressure changes the baseline significantly or if this is a more or less fixed baseline no matter what pressure or mask.

Pugsy wrote:With no mask feature selection I am not surprised that the baseline is not spot on for any of us. I am wondering if higher pressure changes the baseline significantly or if this is a more or less fixed baseline no matter what pressure or mask.

Keep in mind these numbers will vary not only from mask to mask but machine to machine. Plus there is a +/- tolerance to consider which should be specified in the mask manual. I think this falls within that tolerance.

So a number of variables to consider. Remember this is not Rocket Science

GumbyCT wrote:

Pugsy wrote:With no mask feature selection I am not surprised that the baseline is not spot on for any of us. I am wondering if higher pressure changes the baseline significantly or if this is a more or less fixed baseline no matter what pressure or mask.

Keep in mind these numbers will vary not only from mask to mask but machine to machine. Plus there is a +/- tolerance to consider which should be specified in the mask manual. I think this falls within that tolerance.

So a number of variables to consider. Remember this is not Rocket Science

I am positive it doesn't vary from mask to mask as it has no idea what what is being used.

Also I don't think a difference of over 30% is within tolerance.

DougVK wrote:I am positive it doesn't vary from mask to mask as it has no idea what what is being used.

Each mask will in fact vary as will each machine, believe it or not.

GumbyCT wrote: Keep in mind these numbers will vary not only from mask to mask but machine to machine. Plus there is a +/- tolerance to consider which should be specified in the mask manual. I think this falls within that tolerance.

So a number of variables to consider. Remember this is not Rocket Science

I know this. I was asking more out of curiosity than anything else. Not trying to get anything absolute. Just scratching an itch that bugs me a little.

Pugsy wrote:

GumbyCT wrote: Keep in mind these numbers will vary not only from mask to mask but machine to machine. Plus there is a +/- tolerance to consider which should be specified in the mask manual. I think this falls within that tolerance.

So a number of variables to consider. Remember this is not Rocket Science

I know this. I was asking more out of curiosity than anything else. Not trying to get anything absolute. Just scratching an itch that bugs me a little.

I know you know - can you esplain to Doug? I think the numbers are close enuff and this was all human misinterpretations. And not comparing apples to apples.

Of course unless and until we see the graphs that Doug saw we will never know. The reason he doesn't want to show them raises the eyebrows. Hey, I gave it my best WAG.

DougVK wrote:I decided to stick with total leak but here is what I get for the past few nights

Avg pressure 10.7 with a Total Leak of 43.1 with an unintended leak of 15.4 a difference of 27.7
Avg pressure of 10.7 with a Total Leak of 38.1 with an unintended leak of 10.4 a difference of 27.7
Avg pressure of 11 with a Total Leak of 38.2 with an unintended leak of 10 a difference of 28.2
Avg pressure of 10.4 with a leak of 39.1 with an unintended leak of 11.7 a difference of 27.7

At a pressure of 10 my mask should have a leak of around 38, not 27.7. The baseline is clearly incorrect.

If you're going to look at "Total Leak" then ignore the "unintended leak" data.
Those numbers you listed for total leak at those average pressures are very close to what the mask Vent Flow Rate is supposed to be. I don't see a problem.


Den