Acceptable leak rate?

novatom wrote: And use what as a reference then?

Use 80 to 90 L/min if you just have to have a reference to look at.. that isn't exact but it's a lot closer than 24 L/min is.
Your machine does the large leak calculations and makes that flag if needed...not something that SleepyHead does. SleepyHead is just reporting what the machine reports. Respironics Encore software will report the same Large Leak flags if they happen.
Turning off the red line won't do anything to the actual results.
The red line is nothing more than for visual reference...and if you need or want that reference...put it up where it is closer to being accurate than 24 L/min.

Pugsy wrote:

novatom wrote: And use what as a reference then?

Use 80 to 90 L/min if you just have to have a reference to look at.. that isn't exact but it's a lot closer than 24 L/min is.
Your machine does the large leak calculations and makes that flag if needed...not something that SleepyHead does. SleepyHead is just reporting what the machine reports. Respironics Encore software will report the same Large Leak flags if they happen.
Turning off the red line won't do anything to the actual results.
The red line is nothing more than for visual reference...and if you need or want that reference...put it up where it is closer to being accurate than 24 L/min.

Thanks, Pugsy. Are there any other parts of Sleepyhead that I should adjust the numbers for a PR machine?

novatom wrote: Thanks, Pugsy. Are there any other parts of Sleepyhead that I should adjust the numbers for a PR machine?

None that I can think of at the moment. That one little thing about the red line is really the only thing that is arbitrary like that.
I wish Sleepyhead didn't automatically default to have it automatically set at 24 which works great for ResMed users but not so great for Respironics, Devilbiss or the F & P Icons.
It doesn't hurt anything though..the actual large leak numbers and flags don't depend on the actual red line itself...they depend on the invisible red line that the machine uses.
It can cause confusion and panic in those other brand users as they think that they have some sort of massive leaks going on and they really don't...unless they understand their machines better and most newbies are doing good to turn the machine on and get SleepyHead up and running.

Thanks Pugsy. For what it's worth, for the vast majority of nights over the past 5 weeks, my leak rate has been well under 24 so I haven't been too concerned anyways. Now I realize it's only the large leaks that I need to know about.

novatom wrote:Thanks Pugsy. For what it's worth, for the vast majority of nights over the past 5 weeks, my leak rate has been well under 24 so I haven't been too concerned anyways. Now I realize it's only the large leaks that I need to know about.

the only way your leak rate can be well under 24 on a prs1 is to be sitting at 4-5cm of pressure.

are your pressures that low?

palerider wrote: the only way your leak rate can be well under 24 on a prs1 is to be sitting at 4-5cm of pressure.

PR I have seen 25 to 28 L/min total leak with my nasal pillows at my pressures on my PR S1 apap and bilevel and they always exceed 10 cm.
Often I have seen numbers reported that were 5 to 7 cm lower than the charts that show the unintentional vent rates at the pressure I used.
So seeing a total leak line below 24 L/min...I don't doubt it and it doesn't have to be just the 4 to 5 cm pressure.
In fact almost always my total leak numbers were below the listed graph pressures when I had 0 excess leak.

Pugsy wrote:

palerider wrote: the only way your leak rate can be well under 24 on a prs1 is to be sitting at 4-5cm of pressure.

PR I have seen 25 to 28 L/min total leak with my nasal pillows at my pressures on my PR S1 apap and bilevel and they always exceed 10 cm.
Often I have seen numbers reported that were 5 to 7 cm lower than the charts that show the unintentional vent rates at the pressure I used.
So seeing a total leak line below 24 L/min...I don't doubt it and it doesn't have to be just the 4 to 5 cm pressure.
In fact almost always my total leak numbers were below the listed graph pressures when I had 0 excess leak.

well, then... somethings wrong, somewhere

maybe it's that "vent rates may vary" that they put in the manuals

(which is another nail in the coffin of 'mask type is used in leak reporting' theory... if the masks vary that much in venting...)

palerider wrote:maybe it's that "vent rates may vary" that they put in the manuals

(which is another nail in the coffin of 'mask type is used in leak reporting' theory... if the masks vary that much in venting...)

Yep...they can vary and that's why I don't go into a panic with small variations in numbers and why I don't go into a panic if I see numbers slightly in large leak territory. It's not nearly as an exact science as people tend to think it is.

When I have some extra time I will go dig around in my old reports and find a good example to show. I remember the first time I really noticed the lower total leak (lower than vent rate) and I wondered what the hell was going on. Then I got to looking and saw it happened quite often. I think there is a lot more normal "vent rate may vary" than people realize.
RobySue told me she often saw that also..hers was almost always lower than the chart said.

palerider wrote:

novatom wrote:Thanks Pugsy. For what it's worth, for the vast majority of nights over the past 5 weeks, my leak rate has been well under 24 so I haven't been too concerned anyways. Now I realize it's only the large leaks that I need to know about.

the only way your leak rate can be well under 24 on a prs1 is to be sitting at 4-5cm of pressure.

are your pressures that low?

My pressure is set at 6 cm. I'll post some images from Sleepyhead to illustrate.

Found one really good example.. APAP PR S1 minimum of 10 and max of 20.
Swift FX nasal pillow mask which has approx intentional vent rate at 10 of 33 L/min.
So in theory total leak with no excess leak should show 33 L/min but my minimum total leak here is 24 L/min.
It's kinda hard to get good clean example what with the pressure probes and all but I think everyone can see that for the most part this leak line is pretty much at 24/25 L/min area and far below what it should be if going by the vent rate chart.
I have many nights of this but some have some other bigger real leaks and stuff that makes evaluation difficult. And I lost a bunch of SH data prior to Sept 2011 unless we use Encore and we can't see the graph detail as well with Encore. This wasn't a fluke...happened all the time and RobySue had it happen to her also all the time. The charts that come with the mask aren't carved in stone....there is a rather wide variance that is normal.

novatom wrote:

palerider wrote:

novatom wrote:Thanks Pugsy. For what it's worth, for the vast majority of nights over the past 5 weeks, my leak rate has been well under 24 so I haven't been too concerned anyways. Now I realize it's only the large leaks that I need to know about.

the only way your leak rate can be well under 24 on a prs1 is to be sitting at 4-5cm of pressure.

are your pressures that low?

My pressure is set at 6 cm. I'll post some images from Sleepyhead to illustrate.

well, then, 24 is plausable, especially with pugsy's comments about vent rates varying.... at any rate, you're apparently not having any leak problems, and that's the main thing

I'm pleased to report that my leaks are staying under 60, and the only time it gets close to that is when I have scratch an itch around my mouth. Also I don't wake up with a hideously dry mouth.