Sleepy Head Leak Rate Question

(Don't Answer xxyzx, you are on ignore)

Does anyone know how Sleepyhead Leak Rate is arrived at? Is their a calculation done.
Reason I ask is I was looking at someone's leak rate and the the S/H graph showed a rate that was less than what the manufacturer shows as the vent rate for the mask at a given pressure.. Curious how this can happen?

Sleephead can only read the data your machine gives it, all machines aren't created equal.

The two main brands of machines measure leak rate totally differently, one shows mask vent+leak (for people that can do basic math), the other measures just the leak not including not the mask vent, (for those that can't do basic math, and have to guess that the machine they have is set for their mask). Jim

I prefer to do my own math. A paper comes with the mask has a chart of pressure at vent leak numbers.

I think Resmed units measure just other leaks not including vent leaks. (only if you use their masks and are set correctly. I consider this a POOR method.

Remstar or Phillips, combine leaks for a total so they are higher, you just have to check the specs of your mask at your pressure, anything over that pressure is a unwanted leak. Jim (Preferred) by me.

As noted above, Resmed subtracts a mask type typical leak rate from the total leak rate, and that's what is reported. Other machines do things differently.

Incorrect as usual, Leak rate is the output of your XPAP that vented thru the mask plus any leaks! Resmed just thinks you are to Dumb to compute the extra leak on your own, so they guess your mask leak rate, which many users have set incorrectly. So the result is wrong. BAD RESMED!!! Jim

I was agreeing with you Jim.

TASmart wrote:I was agreeing with you Jim.

Was directed at xxxzx. I should have noted that.

klm49 wrote:Does anyone know how Sleepyhead Leak Rate is arrived at? Is their a calculation done.
Reason I ask is I was looking at someone's leak rate and the the S/H graph showed a rate that was less than what the manufacturer shows as the vent rate for the mask at a given pressure.. Curious how this can happen?

What machine?

It depends on the machine and how the leak gets reported.
ResMed machines report only excess leak. Vent rates are removed prior to reporting the leak so those will always be less than vent rate unless the excess leak is quite high.

Now with Respironics machines which report total leak sometimes the total leak is less than expected vent rate by a little bit just because of the normal plus or minus variance of the vent rate. When that happens the person simply isn't having any excess leaks to speak of.
I used to see it occasionally with my Respironics reports on Encore ....leak line for total leak was actually slightly below the expected vent rate for my mask at my pressure.

SleepyHead only reports what the machine records. Doesn't really do any leak calculations except the one calculation for % of time above the red line leak threshold.

Pugsy wrote:

klm49 wrote:Does anyone know how Sleepyhead Leak Rate is arrived at? Is their a calculation done.
Reason I ask is I was looking at someone's leak rate and the the S/H graph showed a rate that was less than what the manufacturer shows as the vent rate for the mask at a given pressure.. Curious how this can happen?

What machine?

It depends on the machine and how the leak gets reported.
ResMed machines report only excess leak. Vent rates are removed prior to reporting the leak so those will always be less than vent rate unless the excess leak is quite high.

Now with Respironics machines which report total leak sometimes the total leak is less than expected vent rate by a little bit just because of the normal plus or minus variance of the vent rate. When that happens the person simply isn't having any excess leaks to speak of.
I used to see it occasionally with my Respironics reports on Encore ....leak line for total leak was actually slightly below the expected vent rate for my mask at my pressure.

SleepyHead only reports what the machine records. Doesn't really do any leak calculations except the one calculation for % of time above the red line leak threshold.

Thanks Pugsy & all (excluding the alphabet poster)
Curious,
So when looking at someone else's leak rate I guess it might be a good idea to see if their "mask type" has been set.
I think I will experiment with my "mask type" setting and see what it does to my leak rate.
I'll report back after a few nights.

klm49 wrote:

Pugsy wrote:

klm49 wrote:Does anyone know how Sleepyhead Leak Rate is arrived at? Is their a calculation done.
Reason I ask is I was looking at someone's leak rate and the the S/H graph showed a rate that was less than what the manufacturer shows as the vent rate for the mask at a given pressure.. Curious how this can happen?

What machine?

It depends on the machine and how the leak gets reported.
ResMed machines report only excess leak. Vent rates are removed prior to reporting the leak so those will always be less than vent rate unless the excess leak is quite high.

Now with Respironics machines which report total leak sometimes the total leak is less than expected vent rate by a little bit just because of the normal plus or minus variance of the vent rate. When that happens the person simply isn't having any excess leaks to speak of.
I used to see it occasionally with my Respironics reports on Encore ....leak line for total leak was actually slightly below the expected vent rate for my mask at my pressure.

SleepyHead only reports what the machine records. Doesn't really do any leak calculations except the one calculation for % of time above the red line leak threshold.

Thanks Pugsy & all (excluding the alphabet poster)
Curious,
So when looking at someone else's leak rate I guess it might be a good idea to see if their "mask type" has been set.
I think I will experiment with my "mask type" setting and see what it does to my leak rate.
I'll report back after a few nights.

Just because the mask has been set doesn't mean it was set correctly, hence errors. Jim

Respironics machines don't have a mask type selection like ResMed machines do.
Respironics machines do have the mask resistance setting thing but that is NOT used as part of any leak calculations.
When I had a PR S1 machine I played with all the mask resistance settings available including off when using my ResMed nasal pillow mask and there wasn't anything anywhere that I could find that changed with any of the settings including off.
I slept all night too at each setting choice....not just a quick 15 minute test while awake.
Didn't feel any difference and nothing different in the data from the machine above the normal very minor nightly variations.