Bipap questions

A couple of years ago I experimented with a BMC G3 B25VT BiPAP. It's basically the Luna G3 BPAP. I had an issue where It would switch to EPAP prematurely, not follow my breathing at all. Unlike say CPAP with EPR at 3. So I couldn't sleep with it and sold it. But now I need to to try again. I'm planning to get the AirCurve 10 VAuto BiLevel Machine. I would like to know if someone can somehow reassure me that this won't be the same case again? Maybe someone who tried both, or just someone who treated UARS successfully with the ResMed.

The B25VT only had S mode for the record, no auto S.

johnydramachase wrote: ↑

Mon Jul 13, 2026 4:24 am

I had an issue where It would switch to EPAP prematurely, not follow my breathing at all.

Most likely, you sensed this while awake. Once you fell asleep, the machine probably worked well.

I started a trial of a BMC GII bi-level 3 days ago.

johnydramachase wrote: ↑

Mon Jul 13, 2026 4:24 am

I had an issue where It would switch to EPAP prematurely, not follow my breathing at all.

I know what you're talking about. And it has to be fixed.

Here's what my breath flow looked like almost all night long when I felt my inhale was truncated. Note that little hump in the expiratory flow, when I'm trying to inhale some more:


There are specific settings to Bi Level machines that you can tweak to keep that from happening.
I don't have any experience with the Aircurve, but keep in mind that a bi-level will not necessarily syncronize to your natural breathing rate.
Sometime iא will. Sometimes you have to tell it what to change.
A very informative paramteter for me to know was the the median inspiration length recorded by OSCAR in my many years of Autoset usage. This was way out of sycn with the BMC. It had a "maximum inspiration length" at which it cut off IPAP that was way too short for my natural breathing. I had to extend the max. I also had to make the machine more sensitive to when I started inhaling. Additionally, the default exhalation sensitivity was too high, meaning it thought I was already exhaling, when I wasn't.

I'm sure the Aircurve is more automated, but in case it doesn't read your breathing correctly, look for what you can define / change in those parameters:
Is there a Ti-Max which tells the machine what the longest inhalation can be?
Is there a sensitivity sensor for when you start inhaling? For me, it was set too low (insensitive). And the default expiratory pressure sensitivity was too high. Between them the machine made me feel like it was truncating my inhales.
It's called "expiratory asychrony"

Here is the info in "ResMed" speak:
https://www.resmed.com.au/healthcare-pr ... technology