Guess I'll get more specific about my question about L/S :^)

Barb (Seattle) · Post by **Barb (Seattle)** » Sat Aug 06, 2005 8:40 pm

0.26? 0.18?

I'm not good at math, so....... I THINK this means that when it reads 0.18 it's leaking less than when it reads .26. Right? It's along with all the other statistics (AHI, etc.) I'm still wondering why the darn mask leaks LOL

Guest · Post by **Guest** » Sat Aug 06, 2005 9:00 pm

This is from our resident statistics expert, derek:

The leak average is also the average mask leakage ... averaged over the whole night. The value includes the leakage through the exhaust port....

(Emphasis added.)

Yes, 0.18 is less than 0.26 and per derek's note, it will never be 0.0 unless your exhaust ports are covered up. (But then you'd be drowning in CO2!)

Guest · Post by **Guest** » Sat Aug 06, 2005 10:02 pm

Check the documentation that came with your mask. With mine there was a chart/graph that showed the "vent flow rate" at different "mask pressures".

Barb (Seattle) · Post by **Barb (Seattle)** » Sat Aug 06, 2005 11:09 pm

Thank you!

sir_cumference · Post by **sir_cumference** » Sun Aug 07, 2005 4:02 am

Err - when I first used the breeze nasal mask I actually had a few nights with 0.00 leakage rate (I also have an autoset spirit). With the swift it is usually about 0.14.

0.00 means it didn't leak at all - and that was really my experience - no leaks for the first few nights. Now it leaks a little, but it's still in the 0.0? range.

sir_cumference (leak free)

Barb (Seattle) · Post by **Barb (Seattle)** » Sun Aug 07, 2005 8:21 am

Well, last night the reading is Leak: .34 and the AHI was 20. The night before was .28 and the AHI 29.9 HUH? Shouldn't the LOWER one (20) have the lower AHI??? *shrug*

I looked at the material..it has a chart that I don't understand LOL

Pressure vs. Leak Rate for the ComfortFull

along the left side it says "Exhaust Leak Rate" (ELR)
along the bottom it says "Pressure"

at the bottom it says "The deadspace assocaited with this mask is between 274 cc and 428 cc.

I think I'll ask the doctor on Monday, ya need a degree from MIT to read this chart LOL

_________________

CPAPopedia Keywords Contained In This Post (Click For Definition): breeze, swift, AHI

Guest · Post by **Guest** » Sun Aug 07, 2005 8:47 am

Is your machine set on autoset or CPAP mode? I would expect your AHI to be lower on autoset? Check your clinician menu to see. And, is your range set wide enough?
sir_cumference

rested gal · Post by **rested gal** » Sun Aug 07, 2005 11:44 am

Shouldn't the LOWER one (20) have the lower AHI???

Not necessarily. Events (apneas/hypopneas) and leaks are apples and oranges, imho.

Massive leaks can certainly interfere with treatment. We'd all like to have no more leaks than the expected "normal leak" of a mask's exhaust port. The machines can handle, as I understand it, some leaking even beyond the amount of "built-in controlled" leak of an exhaust venting our exhaled breath away.

If a moderate or high leak rate is showing up on the data, or yo-yo'ing big spikes on the leak graph are appearing, we don't know if it's a mask leak or a mouth leak (when wearing a nasal mask or nasal pillows/prongs.) If we wake up with air gushing out the mouth, or wake up with a very dry mouth, mouth air leaks are usually the culprit.

Mask air leaks can be difficult to pinpoint just by looking at leak rate. Unless we feel the mask air leak on our face enough to wake us, or the noise of a mask leak wakes us, we might just sleep blithely through mask leaks. If gentle mask leaks don't drive the machine's pressure way up, they're probably nothing to really worry about.

Mouth air leaks are a different matter, though, as those leaks are causing treatment pressure to take a detour out the mouth -- not letting the pressure get where it's needed to keep the throat open.

I'm not a doctor... just my opinion about treatment "leaks" in general.

Barb (Seattle) · Post by **Barb (Seattle)** » Sun Aug 07, 2005 10:37 pm

It's set to CPAP mode on pressure 8. Hmm......gentle mask leaks are what I THINK i'm getting - the hubby hasn't made many comments other than that doggone exhaust port blowin' right on him! He hates it...the other one was routed out and down away from him. I turn over as much as I can, but can't control too much when I'm asleep LOL What you say kind of makes sense. Maybe the pressure just isn't high enough even with all those leaks that the machine says I'm getting. Can't wait to talk to them tomorrow - I'll post what they tell me