AHI and leak

[belrad]

Does AHI numbers are distorted by high air leak?

I noticed today that my AHI=6 (highest so far, I was using CPAP for 6 days) but also I had highest leak=0.18 L/s. I recently changed mask so I wonder does my AHI improved because of new mask or because of air leakage.

On separate note, does anybody know where I can download clinical manual for S8 Elite II. I only got "user manual" with machine, that seems to be missing a lot of information.

Thank you.

[jules]

the resmed machines have a mask menu and the leak rate is the 95 %ile excess based on the mask in the menu

if you change masks, you might need to change the mask in the menu otherwise you might be comparing apples and toadstools

[jdm2857]

If you send me a PM with your email address, I can send you what you want.

As for leak, .18 l/s is not too bad at all. At very high leak rates, the machine may not be capable to push enough air to keep up the pressure, so therapy is compromised. At leak rates lower than that, therapy may be fine, but the increased flow may make it more difficult for the machine to detect and score events properly.

[PST]

What jdm said about leaks, plus keep in mind that the number the S8 gives you is the 95th percentile. 95 percent of the time leaks are less, so you could well have 0 leaks three quarters of the night.