Acceptable leak level?

EncorePro and SH refer to 1) Minutes in large leak, 2) Percent of night in large leak, and 3) Average leak. Which, if any of these, is the best number to look at? Given my pressure level (5-8), machine, and mask (full-face), does anyone know how much of a leak would interfere with my therapy? Is there a general number that's good to stay below? It seems that my leaks have increased, even though my AHI has gone down and I'm sleeping longer. I'm still tired, so I want to rule out or address leaks adversely affecting my therapy.

SleepyHead reports Total Leak which includes the vent rate along with any excess leak as L/min.
Encore Viewer 2.0 reports Total Leak same as SleepyHead.
Encore Pro lets you choose if you want Excess Leak only or Total Leak.

Respironics never gives us a set fixed number where they call it a Large Leak (Total Leak) but from past experience it seems to be somewhere between 80 and 90 L/min. Generally I just prefer to look at the leak line itself and if it is below 70 L/min I know I am good with just a bit of wiggle room above.

[url]http://www.resmed.com/us/assets/documen ... ng.pdf[url]
At 6 cm pressure the vent rate for your mask is 28 L/min. At 8 cm pressure the vent rate is 32 L/min.

I only use the dailies in EP, I prefer the leak to be under 38 LPM but consider under 40 LPM to be OK for some nights. The manufacturers allow more , bui I'm in charge not them, I can see a difference in how I'm doing. I set at 15 CM, so some masks can't hack it for me, do to too high a vent leak rate, I wouldn't even have some in the drawer. Jim

I don't allow large leaks period.

Pugsy wrote:SleepyHead reports Total Leak which includes the vent rate along with any excess leak as L/min.
Encore Viewer 2.0 reports Total Leak same as SleepyHead.
Encore Pro lets you choose if you want Excess Leak only or Total Leak.

. . . "


- and, would you also say that,

ResScan reports Excess Leak only? I would think you'd define Excess Leak (in both ResScan and Encore Pro) as mask leakage excluding Vent Rate.

Included in Excess Leak would be any leakage through tiny holes or tears in old, over-used air tubes as well as any leakage through mouth-breathing during REM sleep relaxation, AND mouth-breathing at any other time as well if using pillows or nasal masks.

Sound right?

Thanks, --Papit

Papit wrote:Sound right?

Sounds right to me.

What is a horrible leak for ResMed users is a nothing leak for me on a Respironics machine reporting total leak.

Most of the time I just look at the leak line and most of the time it is fairly stable with an occasional short lived blip upwards and very rarely comes anywhere near large leak territory. I don't dwell so much on a number I just eyeball the line and go on my way.

ResMed magic line is around 24 L/min. My magic line using total leak reporting is somewhere between 80 and 90 L/min and if I never get above 45 L/min (my mask vent rate is around 35 L/min) then it doesn't really matter what the "numbers" are. At least that is how I look at it.

Hi, Pugsy.

I'm sorry; I'm not quite grasping what you are saying.

What does "vent rate" mean?

When you refer to the "line," are you looking in Encore under Daily Details, Unintentional Leak (LPM)? Last night, mine stayed below 20 for most of the night, occasionally going up to the 30s and never quite reaching 40. Is that good for 5-8 cm pressure? Is that the "vent rate"?

Are the Minutes, Average, and Percentage large-leak figures not accurate/reliable?

Pugsy wrote:Encore Pro lets you choose if you want Excess Leak only or Total Leak.

Which is better to look at? How do you make that choice in Encore?

napstress wrote: What does "vent rate" mean?

Intentional vent or leak rate per the mask specifications at specified pressure.

Encore Pro defaults to report only excess (unintentional leak) and it is stated on the report. You you have to look at what the leak is reporting. Unless you have changed it to Total Leak..what you are seeing in Encore Pro is Excess (unwanted leak) and not your vent rate.

SleepyHead is reporting Total leak which includes the vent rate plus unwanted leak. So you can't automatically compare SleepyHead report to Encore Pro report unless you make sure that you are reporting the same values.

napstress wrote:Unintentional Leak (LPM)? Last night, mine stayed below 20 for most of the night, occasionally going up to the 30s and never quite reaching 40. Is that good for 5-8 cm pressure?

Below 20 L/min for most of the night would be acceptable unintentional leak.
It is L/minute...liters per minute.
Spikes up to 40 would still be at the upper limits of what is acceptable at your pressures.
Yes..when I refer to the "line"...I am referring to the leak line showing on the graphs.

napstress wrote:Are the Minutes, Average, and Percentage large-leak figures not accurate/reliable?

Sure they are accurate and reliable but they are just numbers and average numbers which can be misleading sometimes. The leak line...can't mislead you at all.

napstress wrote:Which is better to look at? How do you make that choice in Encore?

Encore Pro leak reporting to unintentional or Total leak is a matter of personal preference. There really isn't a "better" way to look at it. I like the Unintentional leak myself but others like the other way.
The other way will look like SleepyHead leak numbers. It is up to you which you prefer.
To change it you have to go to the company settings and edit the preference tab where leak reporting choice is given.

Thanks for clarifying, Pugsy.

Pugsy wrote:To change it you have to go to the company settings and edit the preference tab where leak reporting choice is given.

OK, I looked and see that it is still set to report Unintentional Leak, and that's the way I want it. So "Unintentional" and "excess" are synonyms but on the report it is called Unintentional Leak, right? Just want to make sure I'm looking at the right thing.

Pugsy wrote:Sure they are accurate and reliable but they are just numbers and average numbers

I see what you mean. The line gives me more information.

Pugsy wrote:Below 20 L/min for most of the night would be acceptable unintentional leak.
It is L/minute...liters per minute.
Spikes up to 40 would still be at the upper limits of what is acceptable at your pressures.

OK, great!

Pugsy wrote:At 6 cm pressure the vent rate for your mask is 28 L/min. At 8 cm pressure the vent rate is 32 L/min.

If this is the leak rate per mask specifications, then I'd basically want my Unintentional Leak rate to be equal to or lower than these numbers, right? Or at least not straying too far above them for too long, right?

napstress wrote:So "Unintentional" and "excess" are synonyms but on the report it is called Unintentional Leak, right? Just want to make sure I'm looking at the right thing.

Correct. You can use either term because the end result is same meaning.

napstress wrote:If this is the leak rate per mask specifications, then I'd basically want my Unintentional Leak rate to be equal to or lower than these numbers, right? Or at least not straying too far above them for too long, right?

Correct.

When using "unintentional leak" in Encore Pro...give yourself a mental "don't go there" leak number of 60 L/min. That would be very close to large leak territory if you were using Total Leak reporting of 90 L/min as large leak.

Just don't confuse SleepyHead leak number because it is Total Leak and not excess leak. Mark is working on making some adjustments so we can change SleepyHead to report Excess leak but for now it is less than perfect...some people seem to see 2 lines on their reports in SH (one for total leak and one for Excess leak) but not everyone sees 2 lines. We don't know why.
When looking at SleepyHead leak line where you don't want to go.. 90 L/min is large leak territory..if you rarely hit 40 L/min...you are well below large leak territory.

Pugsy wrote:When using "unintentional leak" in Encore Pro...give yourself a mental "don't go there" leak number of 60 L/min.

OK, this is helpful, and it sounds like I'm doing quite well leaks-wise.

Pugsy wrote:some people seem to see 2 lines on their reports in SH (one for total leak and one for Excess leak) but not everyone sees 2 lines. We don't know why.

In SH v0.8.6, I see one line in the Daily tab and 2 lines in the Overview tab. The 2 lines are labeled "Leaks Avg" and "Leaks 90%," but I'm not sure what that means.

napstress wrote:In SH v0.8.6, I see one line in the Daily tab and 2 lines in the Overview tab. The 2 lines are labeled "Leaks Avg" and "Leaks 90%," but I'm not sure what that means.

When you have time..go get the latest Beta version of SleepyHead.
Some neat new stuff in it. You can leave your existing SleepyHead version in place and there is no conflict.
New Beta version actually has a regular installer...so you install it like any other program.
If you use Vista or Windows 7...when at the downloaded folder...right click mouse and choose "run as administrator" command line. This makes getting updates easier.
My Overview in the Beta version is showing messed up leak lines so I don't bother with it anyway.
But the daily detailed shows me a single line but others report 2 lines.

In the Beta version you can choose how you want the averages to be figure...mean...weighted..or average whatever.
90% numbers of anything just means that for 90% of the time you were at or below whatever that number is.

Pugsy wrote:When you have time..go get the latest Beta version of SleepyHead.

Went ahead and got it. Thanks for the encouragement. I'd been procrastinating on it.

Pugsy wrote:If you use Vista or Windows 7...when at the downloaded folder...right click mouse and choose "run as administrator" command line. This makes getting updates easier.

Never saw that opportunity. Tried it at various points but never hit it right. Is it too late?

I looked around the help area, but did not find the answers to these questions: (Here's how I show my gratitude: with an avalanche of questions)
1) How does SH calculate RDI? I chose to see it, since it's my RDI that was high on my sleep study, not my OAs and Hs. But I'm wondering if I'm comparing apples to oranges.

2) What do Session Time, Sessions, Resp Rate, Tidal Volume, Minute Vent, Insp Time, Exp Time mean? If Session Time is what I'm guessing it is, that could be really important information for me.

3) It looks like this version of SH still includes times that the machine is on but mask is off as part of its calculations. I usually run the machine before going to bed to warm up the water a bit, and also had been leaving the machine on while awake in the middle of the night. EncorePro only includes masked-up time, so is more accurate in that regard.

Everything else is pretty self-explanatory. Love the best and worst changes to prescription settings, non-compliance in red, and the pie charts.