+- Apnea Board Forum - CPAP | Sleep Apnea (https://www.apneaboard.com/forums)
+-- Forum: Public Area (https://www.apneaboard.com/forums/Forum-Public-Area)
+--- Forum: Main Apnea Board Forum (https://www.apneaboard.com/forums/Forum-Main-Apnea-Board-Forum)
+--- Thread: My therapy is working great, including flow limitations, right? (/Thread-My-therapy-is-working-great-including-flow-limitations-right)
My therapy is working great, including flow limitations, right? - ThinMountainAir - 09-02-2022
I was diagnosed with moderate/sever OSA about six months ago. After some early struggling, I've come to like my machine. My attitude is, "I've been breathing in and out on my own for over 76 years, it's about time I got a little outside help!" My numbers looks great, as best I can tell. But to paraphrase what many established forum members have said: Don’t be overly focused on numbers, the more important question is: How do you feel? To quote James Brown, “I feel good.” But that’s in part because I’m on supplemental oxygen (I don’t know what James Brown was on). I'm going to ask about oxygen, but first I'd like to ask a couple of things about my OSCAR data.
1. Am I correct that the numbers are good? There are occasional spikes in Flow Limitation but nothing important, right?
2. I believe I understand the basic idea of how CPAP therapy works: When I start to have an apnea or a hypopnea my machine senses it and increases pressure to help keep my airway open. I can see that on my chart at about 2:45 when I had a hypopnea and pressure went from 5 to about 7.5. So far, so good. But earlier, at about 1:45, pressure went from 5 to about 8. Why? I guess because I had a couple of Flow Limitations, but neither high nor prolonged, each lasted less than five seconds and peaked at 0.33. From the forum I understand (I think) that a flow limitation is a sort of mini-hypopnea. If that’s correct, why does my machine increase pressure for flow limitations more than it does for actual hypopneas and even apneas? I'd be grateful for help. I'm hoping that of I understand things better, I'll understand my oxygen situation better, or know what to look for and what data to post.
RE: My therapy is working great, including flow limitations, right? - clownbell - 09-03-2022
As to Question #1, I think your numbers are great. AHI, large leak and flow limitations are very low. If it were me, I would raise minimum to 7 so that EPR can work fully, and that may drive down hypopnea. Here's why - your machine cannot go lower than 4. When minimum is 5 with EPR of 3, you might think exhale pressure would be 2, but no it is 4; in effect your EPR is only 1 rather than the 3 you desire. The trick is to set min to be 4 plus EPR desired, and 4+3=7.
As to question #2, the machine increases pressure AFTER you have an obstructive or hypopnea -- not when you START to have an event. When an event starts, the machine cannot predict how long it will last -- and 10 seconds is required for the event to be flagged as either obstructive or hypopnea. 9 seconds and less > > no flag because the event did not meet the required definition of 10 seconds. As to why the response at 1:45 vs 2:45, I don't know.
RE: My therapy is working great, including flow limitations, right? - ThinMountainAir - 09-07-2022
Thanks for responding, it's nice to have confirmation that my numbers are good. I have this forum to thank for that. I did a lot of browsing of prior posts and made adjustments based on the advice. Last night my AHI was 0.99 and for two nights in a row before that it was zero! So, as long as the numbers are good, including flow limitations, I guess it's not really important why my machine responds to flow limitations the way it does.
Another thing about this forum, it make me grateful for how fortunate I am to have adapted to my machine with only some initial struggling. I should spend more time counting my blessings rather than my apneas. :-)