Decreasing EPR and H and FL increase?

I've been using EPR 3 since I first started CPAP therapy almost a month ago, with two aborted tries at EPR 2. While my AHI has averaged under 2.0 at most pressures, CAs have contributed 60% or more of the AHI number.

So I decided last night to make a real try at EPR 2. With the intent to succeed, I slept through the night. Sleep was not as good as usual, though that could easily have causes other than CPAP settings. Mouth leaks continue as I have seen at these higher pressures.

Looking at SH data, CAs were reduced as I expected. However, Hypopnea index increased markedly over recent amounts. FL is higher than usual too. (OAs are rare, perhaps occurring once every other night; RERA are slightly more rare than OA. I have never seen a UA.)

My questions are whether an increase in H is to be expected when I change EPR=3 to EPR=2, or a change in FL? Or am I just seeing a one-day blip?

BlueDragon wrote: ↑

Sat Jul 07, 2018 11:29 am

I have never seen a UA.)

You'll only see a UA when the machine can't determine whether it's a central or obstructive, and that usually only happens when you're up around 30+lpm excess leak.

BlueDragon wrote: ↑

Sat Jul 07, 2018 11:29 am

My questions are whether an increase in H is to be expected when I change EPR=3 to EPR=2, or a change in FL? Or am I just seeing a one-day blip?

Maybe you're seeing a one day blip, but there's no real way to tell without leaving the machine on those settings for a while.

The flow looks a little rougher, indicating that sleep wasn't as regular.

As to the lower EPR (or Pressure Support if one speaks in bilevel terms), the 'standard' technique figuring out bilevel pressures is to raise epap till the patient doesn't have any more obstructives, then raise ipap till they stop having hypos. snores and flow limitations. So, assuming your lower pressure is high enough (EPR drops lower pressure), then that extra pressure support may help your flow limitations and hypopneas.

Either way, I'd call the numbers on either of those nights 'good enough', you've got a completely insignificant number of centrals, and the hypos aren't too bad on the second night.

If you want to know more, leave it on ps2 for a few nights and see how it averages out... or go back ot the ps3 and don't worry about a few centrals here and there... they don't really disturb your sleep... as I understand it, the problem with centrals is if you start having so many of them that your oxygen starts dropping. If you have an oximeter and just hold your breath for 20-30 seconds, you'll hardly see a blip in your O2 sat... but if you do that *repeatedly* in a short period, you'll see it drop.