Treating low grade CA with ASV

[tossinandturnin]

Higher pressure and EPR tends to cause CA events.

ASV only uses that higher pressure on individual breaths that require it, and only as much difference that is required, as opposed to a fixed difference all the time. And it has a backup rate such that it forces a breath when there wasn't one.
That's quite different to using a high CPAP pressure or EPR.

But yeah - I do wonder if ASV actually triggers more CA events, but because it happens to also have a solution to them it balances out. Hence what I've raised in this thread a few times... maybe ASV is best for when you accept defeat against CAs and resolve to fix it by brute force.

Oscar reports flow limits for ASV in the same way as CPAP/APAP - on its own graph.

[SingleH]

Thanks for that explanation Tossinandturnin, that explains it very succinctly and I now understand the point your are making.

Auto ASV seems somehwat similar to the iVaps mode on the UK version Lumis 150 in that it has independently adjusting EPAP and PS ranges. In much the same way, CA's disappear on this device as backup rate kicks in to force a breath.

[tossinandturnin]

I've pretty much done the opposite of what I suggested above - I ended up reducing EPAP quite a bit and keeping IPAP in the 1.0-6.0 range.. I managed to conclude there was a pretty strong correlation between leaks and hypopneas (real or not). Increasing pressure seemed to compensate for the impact of leaks, but increase the occurrences. Whilst reducing pressure had less occurrence of leaks - but when they did happen the consequences were worse.

So improving my seal, head gear, mouth tape etc has eliminated the leaks and allowed me to use lower EPAP. Hopefully as I get more used to the ASV I won't have the mouth leaks anymore.

I may still play around with the PS range, but at least I know that getting rid of the leaks is important for trusting the data.