HOW do AUTO CPAP Machine work

Auto CPCP machines adjust the pressure based on what piece of informarion, I have a Respironics AUTO Series M. How does the machine know when to increase pressure or decrease pressure.

I want to say it's all magic. But, after reading many posts on this forum, I believe it measures your air flow and adjusts accordingly. Different brands, eg Respironics, Resmed do it a little differently, using a different logarithm.

If you do a search under algorithm + Respironics, you'll find lots of previous discussions. Looks for posts by rested gal, SWS, and Velbor.

Katrina1990,

Also check out the CPAP Wiki on this site. Here's a link to some information on the wiki about AutoPAP:
wiki/index.php/APAP

Happy Sleeper

Heres a video on the Resmed algorithm.
Bascially it looks at the shape of the waveform and as the wave starts flattening, the machine can predict AIs and prevent them.

http://www.resmed.com/us/assets/multime ... 180-v1.wmv

I understand you dont have a ResMed but this will give you an idea of the technology.
BTW, the algorithm has its flaws, for example if you are still awake and dont breath steady, the machine will pick this up as an apnea event.
Im sure its more accurate when your are sleeping, where it actually counts.

Best of luck.
Phi