Strange Flow Rate

[photosmike]

Please review the screen shots and let me know your thoughts.

Thanks,

Mike

[Jay Aitchsee]

I'm guessing a little irregular mouth breathing. Compare your top example to "Expiratory mouth breathing..." from the samples below.


Sample waveforms courtesy of Pugsy and PR

[photosmike]

Thanks,

Mike

[rkl122]

I'm guessing a little irregular mouth breathing. Compare your top example to "Expiratory mouth breathing..." from the samples below.......

Hello. I'm new to forum. Is there an online repository of those sample waveforms? If so, I'd appreciate a link.

Thanks, Ron

[Jay Aitchsee]

Hi, Ron

I don't know of a central location for these images. Maybe you'd like to start collecting them. You could create a Dropbox or similar file location and put them in it as they turn up. Then you could share a link to the file location for all to use. Non of the images are actually stored on the forum. They are all opened by an embedded link in the post. If you use "Quote" to open a post, you can see the link which could tell you a little more about the image, where it comes from, etc. Though most have been found and uploaded to a user's own photo share site, losing the site of origin.

Other than user screenshots of Sleepyhead or ResScan, I think most images originate from the manufacturer's (ResMed, Phillips, etc) websites or from published papers or studies, such as the one above, which originally came from here: http://journal.publications.chestnet.or ... id=1079501. Context could be helpful. This one really only applies to nasal mask users as it was testing a particular type of sensor. Full face mask waveforms would look a little different.

There are few good one here: http://www.osahelp.com/

[rkl122]

Thanks Jay. If I should amass a collection, I'll post a link. At the moment, I'm particularly interested in a flow pattern that would be diagnostic for "being awake." I've seen the odd thread where someone says "...looks like you were awake when those events occurred..." I'm wondering how they can tell.

BTW, I put my machine (PR auto 560 with Aflex) in my profile, but it doesn't seem to be showing. Anyone know why?

Thanks, -Ron

[Jay Aitchsee]

If CPAP.com no longer sells it, it won't link. Just put the name in your profile under additional remarks.

Awake breathing flow is usually more sinusoidal shaped, more irregular, and of greater rate than sleeping flow. The expiratory portion of the sleeping wave is usually more triangular shaped, and the wave is usually more regular and smaller. Look at your results as you are falling asleep to see the change and see the OSA Help link provided earlier for examples wave forms.

[rkl122]

................ Look at your results as you are falling asleep to see the change........

Why didn't I think of that. Doh!

Quite helpful, thanks. -Ron

[Pugsy]

Thanks Jay. If I should amass a collection, I'll post a link. At the moment, I'm particularly interested in a flow pattern that would be diagnostic for "being awake." I've seen the odd thread where someone says "...looks like you were awake when those events occurred..." I'm wondering how they can tell.

Not Jay but thought I would share what I see when I say "looks like you were maybe awake" when someone is asking about the flow pattern.
Incidentally I think the original breathing pattern shown above in the second image looks like probably either awake or semi awake breathing to me. The first one is more iffy and hard to say.
I don't think I have a guideline available, don't know if I kept it, but there was once a sort of explanation showing awake/semi awake/asleep breathing that I saw (don't think I save it anywhere but if I find it I will point you to it) and it helped me figure out or spot probable awake vs asleep breathing. It wasn't perfect and not all breathing patterns are easy to distinguish but it got me close.

For asleep breathing...that's usually fairly easy to spot as the flow rate looks nice and boring and each breath looks like the last one and usually only broken by short periods where we see some sort of reduction in air flow that may end up with some sort of apnea event flag. So study the known asleep breathing pattern first to get an idea as to what the overall pattern looks like.
Then study some known awake time and that air flow pattern and notice how irregular it tends to be.
Study enough of both and you will get an idea of what to look for. It takes a lot of time and studying though and it isn't perfect as there will always be some breathing pattern that you can't really tell for sure.

Arousal breathing...more irregular and we don't always remember waking up so it's still awake/semi awake breathing but we don't remember the arousal/awakening associated with the time frame.

With the ResMed machines it's a little more difficult to see large segments of the flow rate zoomed in at a level to see each breath but with Respironics machines there is a report that shows the flow rate in such a manner that it is much easier to spot the subtle changes. It's called the wave form report and only available when using Give me a little bit and I will go get an image of one of my old wave form reports so you can see what I mean.
I will edit this post and add the image. Will take me a few minutes to open Encore and get one and get it uploaded.

Here you go...I was most likely asleep during all this time but as you can see there's a wide range of normal asleep breathing pattern. I couldn't find one that showed some known awake time ...I don't take long to fall asleep so I don't have much awake time to study. I am sure if I looked through a lot more reports I might be able to find one but I don't have the time at the moment.
This report is probably the only thing about Encore that I really like. It makes for a real easy way to see large blocks of breathing in one image. You may need to click on it to open it to a large sized image for better viewing. This is only available in Encore and only with Respironics machines. The top line is breathing...the red line below the breathing is the pressure line.

[rkl122]

Wow, thank you Pugsy (and Jay). Very helpful. I have EncoreBasic (as well as SH). It doesn't appear to offer a report like that. Is there a more complete version available as a free download? (If it's on the PR site, I'll find it.)

Now that I've thoroughly bushwacked this thread (apologies to OP), let me ask another question: is there also a characteristic pattern for REM sleep?

Here's why I'm interested in this: I've been on APAP for 2 1/2 months. There's been a slow reduction in AHI, but it now seems stalled in the 6-8 region, short of breaking the 5 threshold. I get clusters of events, and some nights, it's a cluster that keeps the AHI from cracking 5. I suspect some of them may occur during brief awakenings. Or during the REM stage (- which I understand would not be unusual). And yes, many of the events occur in the proximity of some "disturbance" in the flow pattern. So I'd like to improve at diagnosing "awake regions" and at least know where the REM regions are.

And once I solve that, I'll attack the great side-sleep vs. supine-sleep flow pattern mystery. (Kidding.)

Thanks, Ron

[Jay Aitchsee]

Well, since it's been hijacked....

Pugsy, I'm not sure I follow Re ResMed and Zooming in. Using Sleepyhead, it appears that the greatest preset Zoom is 1 minute. But that one minute can be further expanded with the mouse and highlighting to display one cycle or less. One can also look at two different time periods with "cloning".

Ron, technically one needs an EEG to positively identify REM. However, I like to look at the entire night, noting regular periods of Respiration Rate Variability that fall roughly as periods of REM would, i.e., the first being 90-120 minutes after sleep onset and continuing with ever shorter periods, as a clue to when REM might be occurring.

edit: Oh, I see Pugsy. Those are multiple sequential periods. Yeah, that would be handy. One could do the same or similar with cloning, but it would be a PITA.

edit II: Ron, I thought you might like this graphic: I've chosen to use CA here, but it could also apply to OA. Note that I have said "likely" in the legend.

[rkl122]

Wow, thank you Jay! I would say most of my CAs and many of my OAs look like the first two examples and not like the third. And based on what I've learned in this thread, it looks like a significant number are also occurring during "waking." (I know this would classify them as "sleep/wake junk," and therefore discardable, but before I dismiss them, I have questions about so-called junk. That's another thread.)

Well. I'm hoping this all means my condition is not as severe as I thought. Won't stop trying to lower the AHI, though.

Thank you again! -Ron

[Pugsy]

I have EncoreBasic (as well as SH). It doesn't appear to offer a report like that.

Encore Basic will generate that report...you just have to know where to look.
On the history tab where you see all your downloads look just to the left of the Summary wording for a little blue paper clip looking thingy. Click on that and you will get the most recent wave form. Be warned it takes a long time to generate that report and you may thing the computer locked up so just be patient. It won't let you go back and see the others though...it only shows the most recent. There is a workaround for it if you want to see older wave forms or you could get the PITA Encore Pro and set a date for whatever wave form you want to see.
Let me know if you want to try the PITA Pro or the workaround so that you have more than 1 wave form available.

I have never been able to spot REM sleep stage by looking at the breaths. I know some people say they can get a good idea but I have never been able to spot it myself. I can sometimes spot probable REM by looking at the pressure line because often my pressures go up when in REM but it isn't always clear cut.

[rkl122]

............

Encore Basic will generate that report...you just have to know where to look.
On the history tab where you see all your downloads look just to the left of the Summary wording for a little blue paper clip looking thingy. Click on that and you will get the most recent wave form.

Whaddaya know. Hadn't noticed that thingy before. I've learned a lot today. Thank you.

...........Let me know if you want to try the PITA Pro or the workaround so that you have more than 1 wave form available.
............

The only reason I'd want another version of Encore would be for comparing these particular traces, one night against another. But it's not worth it to me to pay for the privilege or to go through tedious workarounds. If there's a free download of pro available, then yes, I'd be interested. In any event, thank you for the additional help and advice.

-Ron

[Jay Aitchsee]

The only reason I'd want another version of Encore would be for comparing these particular traces, one night against another. But it's not worth it to me to pay for the privilege or to go through tedious workarounds. If there's a free download of pro available, then yes, I'd be interested. In any event, thank you for the additional help and advice.

Again, you can compare traces of one night against those of another by using the "clone" feature of SleepyHead. Not as extensive as Encore, but easy for one time period.