CPAP mode on the S8

[GagReflex]

Apologies, More newbie questions!

After being diagnosed with a AHI in the 50's and during a four week trial of CPAP, I've gone out and purchased the Resmed S8 II Spirit & software.. This is a similar machine to the Vantage sold in the US. I also bought the Swift II mask.

I had trialed a fixed pressure of 10 without drama (The hire machine was the Remstar pro M Series with C-Flex ) but thought the Auto would be a better option.

The Swift was set up for a minimum pressure of 8 and maximum of 12.
what I hadn't realised was the Swift doesn't have EPR in Autoset mode.. I found it really hard to get to sleep with it set this way. Breathing out was sooo hard after the C-flex I was used to.

The next night I set it into CPAP mode with EPR enabled. I set it to 10.0 cmH2O which it what I was using on the M series. Waaaaaaay better, in fact I think it was better than the c-flex.

Looking at the stats via the ResScan software:

When in Cpap mode and set to 10.0 cmH2O, the stats tell me Median 8.8, 95th Percentile 9.0 and Maximum 9.6.

Why are these figures less than 10??.. I do have some bad mask leaks, the Swift II is fine to start with, but after about 2-3 hours of sleep the leaks start and get really bad, I'm working on that, but would that affect the figures? My AHI isn't great at around 7.0, although its far better than it was.. Once i get the leaks sorted, hopefully that'll come down.

Thanks again.. This forum is awesome

[alnhwrd]

Its probably because the EPR is enabled. You are still getting 10 CM of pressure, but since the EPR drops the pressure by 1, 2, or 3 cm to ease your exhale, the machine records it as a lower pressure, hence the lower average for the night. At least that is how mine, which is a straight CPAP, works.

I have terrible leaks with my Swift II, even when I tighten it down very tight. What is your leak rate?

[GagReflex]

I start out with zero leak rate, and it stays like that for the first few hours I'm asleep. but after that.... My 'median' leak rate is around the 11 mark, maximum 37.2!..

I've been sleeping with the hose down, I'm going to try it tonight with the hose up to see if that makes any difference. I suspect i'm rolling over onto the same side as the hose (side sleeper).

[dsm]

Hi

I have been using an S8 Vantage as my backup machine & always run it in CPAP mode with EPR set to 3.

This to me is a very workable arrangment & the more I use it the better it feels.

My Cpap CMS is currently set to 13.6 so EPR=3 will drop exhale to 10.6 CMS The stats show an average of something like 12.2 which is how the machine shows the effect of EPR lowering. It just averages it out from the total CMS applied in the two pressures.

This machine in EPR mode is the nearest thing to a simple bilevel. What makes it nearly as good in some respects is that the rise & fall is determined by your breathing (no confusing risetime settings to worry about) & works well when you get used to it (at first it seemed sluggish to me but I have some aggressive rise & fall settings on my regular BP330 bilevel).

The other thing is that as soon as you exhale, if you don't start breathing in within a couple of seconds the machine while in EPR mode will resume normal pressure & that to me is like having a timed bilevel and for me this is a great feature as I have a tendency to breath slowly, the sometimes stop at an exhale. This machine's ability to quickly resume normal pressure seems to get me past this problem.


Good luck with your unit

DSM