Machine Reported AHI question

[brsett]

I am very new to CPAP (4 days) and have a PR System One A-flex machine (in C-Flex+ mode). I run at 7cm/h2o and use a SwiftFX nasal pillow (currently using the medium pillows). My machine currently reports 1.9 as my 7 day AHI. That works out to about a 3.3 AHI given that I haven't been using the machine for the full 7 days.

My question is, how does the machine know that? I am not using my chin strap, and have woken up in the mornings feeling pretty rested, but with my mouth open and air streaming out. Could it be missing apneas because my mouth is open? I'm willing to mess with the chin strap (or maybe mouth taping), but don't plan to bother if this works well enough. I'm willing to try to get my AHI down to 0, but honestly, if I'm able to get to <3.5 easily, without even bothering with chin stuff, I probably will just stick with where I am. Is my thinking off here? I'm not interested in geeking out on this machine if I don't have to. I'd rather just use the bare minimum of gear, and get to a reasonable AHI rather than work at it really hard for a 0 AHI. Is a 0AHI worth the hassle?

[Stutz427]

First, no matter what, if your mouth is leaking, you are not getting the right treatment. While you do want to get the numbers as low as possible, just because you have low numbers, and given what you have told us does not mean you are getting good treatment. For instance, I have had a couple of nights where the masks leaked so bad I did not show any AHI. But, I was not getting treatment, it just did not show up. So, I would get a chin strap, see where that takes you. For a couple of nights you can make one from an ACE bandage. I personally also tape my mouth but some people are afraid of that. Check your numbers once you do that. I also think it will take a little while to feel the difference

[Pugsy]

What does your average leak say?

Absolute zero AHI is rare. If you are losing huge amounts of air through your open mouth, then you are losing therapy.
The machine can only compensate for this huge leak up to a point. It is possible that huge leaks will also impact the AHI data meaning what gets reported may not be accurate.

So we have to look at AHI AND leak rate to have any semblance of an idea if the therapy is working. It all depends on how long you have had your mouth open when you wake up. Only way to know for sure is with the software reports. General averages are just that, averages. Averages can often be misleading. Especially those 7 day and 30 day averages.

[brsett]

The machine doesn't report any leaks (0% and periodic breathing is 0% also, not sure what that is). I'll probably try the chin strap for two days, just to see what happens, but I have to say that using the chin strap seems like a major pita. I already have a chin strap, so its no cost to try it. But why can't I just try and slouch through without it? My OSA caused health problems weren't all that severe, I was just tired of being tired. And, although I acknowledge that placebo effects/confirmation bias are hard to account for, I do seem to be waking more easily. Is the treatment here not a continuum? Will I really get 90% more benefits with an AHI of 1 versus an AHI of 3 or even 10?

[Pugsy]

Will I really get 90% more benefits with an AHI of 1 versus an AHI of 3 or even 10?

Yes, more benefits from AHI of 3 than AHI of 10. Not such a huge difference "maybe" between 1 and 3. All depends on your body.

I feel like crap with AHI of 5, decent enough with AHI of 3, even much better with AHI between 1 and 2. In theory it shouldn't make that big of a difference but for me it does.

So many other factors can affect how we feel besides one set of numbers. Give it a couple of weeks and see how you report things.
Work on the open mouth thing. It is important.