Help understanding OSCAR data / optimizing treatment

Hello! I was diagnosed with sleep apnea less than a year ago (18 AHI, OSA), and I'm at the point now where I'm trying to better understand the data I'm getting from OSCAR — and how I can use that info to help improve my treatment. I read over Pugsy's Pointers — Oscar tutorial, etc., which was super helpful (in helping me not to freak out about certain numbers I think I was misinterpreting!).

My average AHI is usually between 2 and 4. It rarely goes above 5. Overall, I'd say I feel rested. Headaches and brain fog have stayed away, thankfully. But I've noticed over this past month I'm not able to sleep through the night (like I did when I first started using CPAP). I'd like to find ways to troubleshoot this. And I want to be sure my "numbers" are okay (leak rate, centrals).

I switched from one full face mask brand to another about a month ago. Is there normally an adjustment period with a switch like this? My 95% leak rate was 0, for months, until I changed masks (I think). Also, I noted my centrals increasing with the mask change. Still within an okay range?

My sleep doctor advised me to keep the pressure at 4 to 20. I learned later that this is not ideal. So, over the past couple of weeks I've been slowly upping the lower number. I'm up to 6.4 now. Could this have anything to do with more leaks / centrals? Still keeping the higher end at 20.

You need more minimum pressure. I would recommend you try 8 or 9 cm.

Thanks so much for the input. Could you tell me how, from looking at this data, you have a sense of what the min pressure should be? I'd like to have a better understanding myself of how this all works.

Also, when increasing pressure, is it best to do it incrementally, over time? Or okay to jump from something like 6 to 8?

As the machine's default low pressure is 4, if you need a little boost, going to e.g. 6 is a good start, so it's not about which specific number at this point is, just that a little more would be good to try out for a few nights and then see how you feel and what your AHI looks like.

Thanks, Julie! Tonight, I'm trying 7 pressure. Will work my up and note how I feel / what AHI is along the way.

I'm getting the sense, from reading a lot of posts, that finding the ideal pressure (for an individual not working directly with a sleep med professional) is done mainly through trial and error. And that the span of pressure (from low to high) is best if it's not too far apart. (Is this correct?)

Looking at my charts over a period of time, if I'm seeing that my pressure never goes above 11, would it make sense to lower that top pressure #, say to around 14 or 15?

Newbie questions, I know! I'm really just trying to have a better understanding of my OSCAR data and how that plays into better troubleshooting. I appreciate all your help.

jleica wrote: ↑

Sun Aug 16, 2020 7:51 am

Looking at my charts over a period of time, if I'm seeing that my pressure never goes above 11, would it make sense to lower that top pressure #, say to around 14 or 15?

You could limit the max but it changes nothing if the machine never goes above 11.
I don't understand why people feel the need to limit the max. If it could go to 100 and it never went past 11....it doesn't matter one whit what the max is set at. Doesn't change the response...doesn't change how the machine does its job...doesn't do anything.
Now it doesn't hurt anything either but there is no reason to limit the max if it never ever goes above a certain setting.
Your car can likely go to 120 MPH....do you govern it so it won't go to 75 MPH? Or do you just keep your foot off the accelerator? Would governing it change how it functions?

jleica wrote: ↑

Sun Aug 16, 2020 7:51 am

Looking at my charts over a period of time, if I'm seeing that my pressure never goes above 11, would it make sense to lower that top pressure #, say to around 14 or 15?

If I had a bathroom scale that that had a maximum capacity of 300 pounds, but my weight never went more than 200, would it make sense to replace it with a scale that had a lower capacity, say around 240 or 250?

Makes total sense, Pugsy and Dog Slobber. Got it! Thanks.

The only time that the max setting might need to be limited is IF (big IF) the machine wanted or needed to go higher and the going higher caused some sort of problem that was worse than the reason it was wanting to go higher.

Example...what if the machine sometimes wanting to go to 11 (but never went beyond 11) but that 11 caused bad aerophagia issues and when it maybe hit 10 there were no aerophagia issues. In that situation we would want to limit the max to probably 10.

Or another example....Someone has a lot of flow limitations and the machine really wants to increase the pressure in response to those flow limitations but the more pressure causes bad aerophagia issues. The belly issues are a bigger problem than the flow limitations are a problem.

Now if someone just wants to limit the max just to limit it because it makes them feel better knowing there is a limit that is never ever going to be hit....it hurts nothing but it's a mental thing which is fine and probably important to some people and that's fine too.
It is why when I see reports with the max limit of 12 and I don't ever see a report where the machine ever goes above 10 that I don't say anything. It doesn't matter if the limit is 12 or 20 or 100 if the machine could go there.

I use a bilevel machine and the max is 25 and I never see it go above 16 and it's rare that it hits 16 and when it does it's probably when I am in REM sleep which is when my OSA needs more pressure. I still leave the max at 25 because for me to change the max to 17 wouldn't change a thing at all in terms of anything. There are people who think that it changes the auto algorithm response....it doesn't. Response is the same no matter what the limit is set at. It becomes a moot point.

But again if someone wants to limit the max and they know they never ever go higher than whatever...and they aren't having any reason to not go higher like aerophagia....it hurts nothing to limit the max.

Now if someone thinks that limiting the max improves or changes the therapy itself or the machine's response...it won't.

I like having it open just in case something weird happens and I might remotely have the need for higher pressures. Odds are I won't but having it wide open covers all the potential bases and since I don't have aerophagia issues or centrals popping up or whatever then there is no reason for me to limit things.

Learning a ton here. I appreciate your response.

Couple things caught me eye here:

1. Aerophagia issues. I struggle with that at times — but it comes and goes. Maybe once or twice a week I have to pop a Gas-X in the middle of the night. That helps a lot. Too soon for me to tell if my pressure setting adjustments are affecting this, I think.

2. Centrals. Pugsy, in your OSCAR tutorial you mentioned that five centrals an hour would be reason to call one's doc. Don't think I'm there, but I'll keep an eye on that.

Feels like I'm learning how to play another instrument, and I'm trying to find the right ... chords, I guess.

jmrose wrote: ↑

Sun Aug 16, 2020 10:29 am

Feels like I'm learning how to play another instrument, and I'm trying to find the right ... chords, I guess.

that seems like a good way to put it. most doctors don't really know what a cpap actually DOES. they seem to think that their job is to prescribe one and then HEY! PRESTO! no more sleep apnea.

no, it takes a lot to optimize a machine's settings. and it's all down to jmrose and how his/her body and mind handle it. so tweaks will occur for you that won't for me. and vice versa.

i notice one of your posts generated response about narrow gap in min and max. but they seem to have missed your other, which called this trial and error. in a way, it is. but you aren't just guessing and moving things about. we call that dial winging and it makes no sense. what we need is to track you're sleep with the software, oscar, and post charts from that.

then we can see what actually settings need tweaking.

so stay here, in this thread, for a bit, won't you? that makes it easier for the experts to keep track of you.

btw, if you don't know it, pugsy and dog slobber are two of our top people. so pay close attention to any advice they give you.

good luck!

Zonker, about docs: EXACTLY! That's what I gather from reading other people's posts. I have only seen one sleep doc in my sleep apnea journey so far, and he was so confused by my question about my charts and making any pressure adjustments. He's never seen my charts — he asks me how I feel, and that's the end of that.

Speaking of which ... charts ... I posted three days of OSCAR charts along with my original post. Are they not showing up? (I can see them on my screen, when looking at my post in the forum.) Just in case, I'll try posting them again, here.

Trial and error it is — but I want to be as responsible as possible as I move forward with tweaks. Informed tweaking.

For sure, I could see that pugsy and dog slobber were very experienced on this forum — and I am definitely paying close attention to their advice and words of wisdom.

jmrose wrote: ↑

Sun Aug 16, 2020 1:04 pm

Speaking of which ... charts ... I posted three days of OSCAR charts along with my original post. Are they not showing up? (I can see them on my screen, when looking at my post in the forum.) Just in case, I'll try posting them again, here.

Trial and error it is — but I want to be as responsible as possible as I move forward with tweaks. Informed tweaking.

For sure, I could see that pugsy and dog slobber were very experienced on this forum — and I am definitely paying close attention to their advice and words of wisdom.

oscar_aug06_2020.pngoscar_aug08_2020.pngoscar_aug13_2020.png

dang it! my apologies, sir/madam. sometimes, i read too many posts and users blur together. yes, i DID see your charts. they are quite plainly there.

me? not plainly here.

No problem, zonker! (I started seeing some posts about attachments not uploading here because of space reasons and thought maybe that's why you didn't see mine.)

Few more details, in case this helps: I'm a 60-year-old female, in good health. Mouth breather — deviated septum. (I'm working on ways to decrease the mouth breathing. I can feel my jaw dropping open at times. I'm considering trying a soft cervical collar). Side/back sleeper.

For months, I was sleeping through the night with my CPAP. In the past couple of weeks, I find myself waking up a lot throughout the night. Lots of early-morning waking, too. I can still feel the benefits of the CPAP, though, and feel rested for the most part, but I don't think I can sustain this kind of sleep over the long haul.

What's happening now w/my sleep seems to be coinciding with trying a different mask, the F+P Vitera (it's actually more comfortable for me, but has a higher leak rate than the Air Touch F20 I had been using), and also slowly bumping up the pressure — I'm up to 7 now. (Had been on 4.)

Jmrose, the soft cervical collar would be a great idea to try. You can see some clustering of events in your charts, and it's possible they reflect a bit of chin-tucking, which can constrict the airway. A collar might help with that along with helping you keep your jaw up.

I also see that the increases in your minimum pressure don't correlate with any increases in your CAs. In fact, the CAs have gone down as the pressure has gone up. CAs tend to bounce around, so there isn't a lot to conclude from these limited number of data points. Still, so far you have no reason to worry that increasing your minimum will increase your CAs.

It's up to you how to proceed, but a general rule of thumb is to try one change at a time so you can tell what is/isn't working. Maybe try the collar first to see whether it helps with the clustered events? And if it doesn't help, then maybe try increasing your minimum pressure gradually?