Why all the fuss about Leak values?????

I'll try to give my observation. When Mike has a rare large leak beyond the machine's sensor, what wakes me up after about 20mins of leaking is not only the hissing of the mask but I also know the sound of apneas. It happens when he tries to sleep on his tummy. Yet when I check the data in the AM for that period there are no events recorded that correlate with the LL shown. Jeff, is that what you mean? Or did I confuse things?

jnk wrote:

Physician wrote: . . . But there were no AP or HY events . . . .

But how would you know that, if for several minutes the leak was above the amount that allows the machine's sensors to "see" events?

How do you know that for those few seconds the machine was not capable of sensing said events, and even if they were, why would those isolated events be clinically significant ?

In any event, by modifying ResMed's defective strap arrangement, my leak rate on the LCD this AM was ZERO (0.0).

DoriC wrote: . . . when I check the data in the AM for that period there are no events recorded that correlate with the LL shown. Jeff, is that what you mean? . . .

Yes, Dori, that's exactly what I mean.

Physician wrote: . . . How do you know that for those few seconds the machine was not capable of sensing said events, and even if they were, why would those isolated events be clinically significant? . . .

Because ResMed says so, as I posted earlier: ( viewtopic.php?f=1&t=57089&st=0&sk=t&sd= ... 15#p536781 ) Also because the percentage of flow difference caused by an event is undetectable if there is enough flow escaping around the mask to sound like a fog horn.

My understanding is that the point of therapy is to maintain a pressure, which can only be done when large leak is not present.

My understanding is that the point of data is for the machine to record events, which can only be done when large leak is not present.

It is not my understanding that the point of masks and machines is to design them so that they all fit Physician's preferences perfectly.

I consider all events significant, but hey that's just me. I have very severe OSA.

Most important, the point of "all the fuss about leak values" on this board is to educate those who are unaware of the problems large leak can cause, just in case they actually want to know. Some people do. Some would rather not know. But hey, that's cool.

Most docs, RTs, and techs don't seem to care much about leaks. So I'm glad there were fellow patients on this board who pointed me to statements made by manufacturers and shared their personal experience with me to help me see that keeping leak low made them feel better for very logical reasons.

That's what this place is about for me.

Speaking of leaks, just downloaded all my S9 data into ResScan. In the past week when that 7.2 leak repeatedly appeared every night and created concern, the printout shows a MEDIAN LEAK of 1.2 L/min. and a MAX of 120 L/min. and AHI = 1.0

I just reviewed my Resscan charts and noticed that every time a leak was recorded the flow rate was noticeably less. So leaks do matter. It impacts the actual flow of air into your lungs. How much that change matters is probably a very hard-to-answer question as everyone's situation and body, and body response, is different.

When my husband has a somewhat leaky night(doesn't even have to be large leaks), he doesn't feel as rested even though his AHI remains low.

Be sure you're not using too small a nasal mask. I have a smallish nose, and use the large original Swift nasal pillow.
Also, I discovered with my ResMed Autoset Vantage S8, that I have a leak somewhere in my humidifier. I have to tape up all the seams and redo it every couple of weeks, depending on my leak rate. I tried everything, trying to get that leak rate down, and then someone here suggested that it might be the humidifier, and sure enough, it was!

DoriC wrote:When my husband has a somewhat leaky night(doesn't even have to be large leaks), he doesn't feel as rested even though his AHI remains low.

The graphs I looked at for myself show no meaningful correlation whatever between leaks and events.

idamtnboy wrote:

DoriC wrote:When my husband has a somewhat leaky night(doesn't even have to be large leaks), he doesn't feel as rested even though his AHI remains low.

The graphs I looked at for myself show no meaningful correlation whatever between leaks and events.

For some, I believe, leaks can cause arousals that do not cause events but that destroy sleep architecture just the same and make them feel unrested in the morning. That is one reason that some view the leak line as being more important information for them than the AHI figures, as far as how rested they feel anyway.

jnk wrote:For some, I believe, leaks can cause arousals that do not cause events but that destroy sleep architecture just the same and make them feel unrested in the morning. That is one reason that some view the leak line as being more important information for them than the AHI figures, as far as how rested they feel anyway.

Makes sense.

jnk, that's what I just said!

DoriC wrote:jnk, that's what I just said!

Yeah, I know, but you said it way too clearly, so I was trying to muddy the waters a bit.

I was just trying to make sure your point was made by saying it several times with different words.

I'm still not sure we've convinced Physician.

jnk wrote:

DoriC wrote:jnk, that's what I just said!

Yeah, I know, but you said it way too clearly, so I was trying to muddy the waters a bit.

I was just trying to make sure your point was made by saying it several times with different words.

I'm still not sure we've convinced Physician.

Convinced me of what ? Please share and/or restate.

I took my graph to several certified sleep docs. It was agreed that the leaks were exceedingly brief, insignificant, AHI <0.5, and everything was fine.

We all agreed ResMed should add MEAN LEAK to the LCD Sleep Report and the vertical straps should be adjustable.

Physician wrote:Speaking of leaks, just downloaded all my S9 data into ResScan. In the past week when that 7.2 leak repeatedly appeared every night and created concern, the printout shows a MEDIAN LEAK of 1.2 L/min. and a MAX of 120 L/min. and AHI = 1.0

I wonder if you were trying to check the data immediately after turning the machine off. That processor has quit a bit of data reading and caltulating to do immediately after the machine is turned off, it needs time. I saw at 7.2 leak rate one time -- when I pressed the review buttons immdieately.

As for not "needing" graphs: I disagree. A statistic of central tendency -- be it average, median or mode -- will never give you the information you need for troubleshooting. Only a graph shows you what happened when.

jnk wrote:

idamtnboy wrote:

DoriC wrote:When my husband has a somewhat leaky night(doesn't even have to be large leaks), he doesn't feel as rested even though his AHI remains low.

The graphs I looked at for myself show no meaningful correlation whatever between leaks and events.

For some, I believe, leaks can cause arousals that do not cause events but that destroy sleep architecture just the same and make them feel unrested in the morning. That is one reason that some view the leak line as being more important information for them than the AHI figures, as far as how rested they feel anyway.

In my infancy in the CPAP journey, am already noticing that when I wake up feeling like c**p, having woken up several times - checking my graphs from the previous night almost always turns out to show significant leaks at the time I woke. Events don't always correspond with wake up times, though. I do make a note of the time/s I wake up.

Am also starting to notice that when my fasting glucose numbers are higher, my sleep wasn't great either.

Cheers,
Xenablue