(08-15-2015 08:55 PM)Hanrahan Wrote: Out of curiosity last night I set my Resmed 10 Auto to a max of six, trying to find my baseline AHI. Because I am trialling masks and I'm back on a small pillow I felt I wasn't getting enough air so I increased that to 7.
After 4hrs sleep [pretty good for me] I registered 2.3 AHI/hr.
My dilemma then is why the auto machine takes me up to 10 cm, a pressure that I am quite uncomfortable with and which, perversely, disturbs my sleep? In my initial sleep test I registered 22 AHI but disturbingly, zero SWS and <7% REM sleep. In the equipment test the technician found 7 cm effective but that was inconclusive because I hardly slept, partly because the air-con was freezing.
Would a non-auto [manually set] machine be cheaper and just as effective? I think the Resmed Auto is about $2,300 dollars here and masks $200. One that I don't have to don my glasses to read the screen would be nice too.
Still looking for answers
Edit: Maybe this should have been in a new thread. It sounds too much like a "Me" post, but I did want to raise this topic. As a newbe, I am in no position to advise the OP. Sorry.
Auto machine algorithms are 'heuristics'. They typically respond to flow limitations and snores in an attempt to ward off an apnea event. The thinking behind this is that a collapse of the airway leading to apnea is preceded by snores and flow limitations. Resmed machines are more aggressive in raising pressure than Respironics.
The problem with this theory is that at a certain pressure, snores and FLs no longer proceed to full apneas. But the machine has no way of knowing where to stop as long as it sees the snores or FLs.
That is why a lot of sleep docs use an auto for titration and then set a fixed pressure equal to 95%ile pressure given by the auto.
In your case, since your pressure needs are low (< 12cm), you can easily get on a fixed pressure cpap.