wildly jagged flow rate curves -- do you see this in your data? - Printable Version +- 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: wildly jagged flow rate curves -- do you see this in your data? (/Thread-wildly-jagged-flow-rate-curves-do-you-see-this-in-your-data) |
RE: wildly jagged flow rate curves -- do you see this in your data? - cathyf - 10-15-2021 Ok, so I'm kind of leaning towards something positional rather than EPR/PS here -- because that March 24th train wreck is at EPR=3, but back sleeping with no cervical collar. Here is the whole night-- https://www.dropbox.com/s/7s49ctd0kitlydz/2021Mar24_full.png?dl=0 Notice from 12:40-12:50 or so is a big cluster, with a littler one at about 12:20, a run of extended flow limits, and then a long run of crazy respiration rates. And here is 8 minutes spread out starting from about 2:15, where I'm coming out of an extended run of the wacky breathing. At 2:17:50, that looks like arousal and recovery breathing. After a good two minutes of that I finally drop into a more regular normal rythym. https://www.dropbox.com/s/zt8yod0tubjj62j/2021Mar24_zoom2.png?dl=0 Here is another 8-minute run as I'm coming down out of an episode. https://www.dropbox.com/s/e5w2gyidy2yy7x8/2021Sep15_zoom.png?dl=0 Again, notice the arousal & recovery breathing kicks me back into a more normal rhythm. This one has pulse-ox data, too, and my heart rate is not low. Again, this is EPR=3 on the autoset. Here is a much looser zoom, a bit over an hour, that shows the entire incident, starting with normal breathing, crazy respiration rates, then settles back down again. https://www.dropbox.com/s/bf64miq848pnw33/2021Sep15_zoomLoose.png?dl=0 The heart rate is in 70s/80s throughout. The hubs and I have noodled around some ideas about how to measure beyond the sensors in the cpap. Hubs says his first instinct would be to put pressure sensors lined up all the way down the hose and up in the mask, too. I was curious about the sleep study and whether my flow rate curve during the test showed any of the wild gyrations that the cpap machine sees. And whether the belts used might have been able to measure and detect TAA and see if there was anything of that sort going on during that sort of breathing. Of course prying that information out of them is probably impossible! Also, this is off-topic, the reason that I know that the study was measuring thoracic and abdominal effort is that at the end of my sleep study is a detailed explanation of the scoring and definitions of terms. Because these people are jerks, the study that they sent me was the scan of a printout rather than a pdf, so I had to run it through OCR to turn it back into text. (I took it as a personal challenge, LOL.) Now that I've got it as text, I thought that I'd share -- maybe it would be useful for the archives somewhere? Quote: RE: wildly jagged flow rate curves -- do you see this in your data? - Geer1 - 10-15-2021 EPR/PS isn't the cause, it just has a history of improving this and the data you posted in other thread supported that it helps you too unless that data wasn't average for you. The cause is likely some mixture of flow restriction/obstruction, position, bad night etc increasing respiratory effort. One thing to note is that your heart rate was slightly elevated during that breathing. Before and after your heart rate was regularly below 75 BPM, during it was rarely below this and it appears to go as high as 90. I think that is just a slightly elevated heart rate because of extra effort during the asynchrony/restricted breathing. Try PS = 0 on your vauto if you don't believe PS has an affect. PS=0 removes all the extra features a vauto offers(timing controls, higher PS, higher pressure etc). At that point the only difference is the colour and letters on the front of the machine and I doubt either makes a difference. RE: wildly jagged flow rate curves -- do you see this in your data? - 2SleepBetta - 10-15-2021 The attachment is an annotated image from the second linked item of your post above. I stretched out the 30,000 ft. view and believe it shows your wave shape, as least where sampled, has a lot of NED scooped wave shapes obscured by distant views. Superimposed cardio effects have to be imagined. [attachment=36422] RE: wildly jagged flow rate curves -- do you see this in your data? - cathyf - 10-15-2021 2SB -- I'm not sure I'm buying this... Here's a much more zoomed view of one ending of whatever it is https://www.dropbox.com/s/yuk5nsil90664st/2021Sep10_2minZoom.png?dl=0 Between 23:40:10 and 23:40:20 I clearly come out of it, and those breaths later look like they have some NED going, but before that is a much wilder ride than I've ever seen published as "sleep disordered breathing". Here is a very wide view of what I linked the zoom of the end of: https://www.dropbox.com/s/w6sdqdnv1vr0kuj/2021Sep10_zoomLoose.pdf?dl=0 There's plenty of "normal" ugly on both sides, but what's in the middle looks way uglier to me. RE: wildly jagged flow rate curves -- do you see this in your data? - 2SleepBetta - 10-16-2021 I understand, you not buying it, Cathy. Some of my waves of the kind discussed here are like yours with I-tips that markedly dip below the 0-axis, briefly, between full exhalations, Some are like the latter part of the within- wave NED progression. The two forms mingle, mostly in short runs, and keep company with each other and variant undesirables. The key distinction between your and my deranged waves is how yours mostly rise to a sharp peak so quickly and long before full exhale starts--yielding what I call chair seats (inviting cardio dips?). Any chance you'd post/dropbox a zoom from the source of that second link: 2021March24_zoom2.png, 02:15:20 to 02:17:4, the zoom filling a 1-inch+ channel window height? I'd like to ponder it and see if my pulmonologist, a partner in a sleep lab, would comment on it and on one of mine that is similar and mixed. That time span includes waves I think are NED-like as well as about 5 waves with those small "exhalations" between two full exhalations. Corresponding FL, mask pressure and leak zooms, too? I'm always interested in the waveform transitions, form to form, along with accompanying most-related metrics. Looking at your most recent curves cast suspicion on the sigh waves I've considered completely benign (still think so). But can we relate how they morph into troubling forms, no rather, what factors cause or occur with our breathing disorder to increase and cause wave forms to degenerate? How do mask pressure, FL and leak relate? Re the two questions: I've long had sighs the peak I-tip FR of which would begin to drop and then a second inhalation burst would shoot FR sharply higher before the FR sharp dive to 0-axis and peak exhalation rate. I call 'em lop-eared rabbit heads. At 30,000 feet they show up, like old telephone poles sticking up by country roads, all along my FR curve, varying some from a 10 minute interval. Always gapped, the algorithm never showed confusion. Half of them would have a 0.1 to 0.2 FL flag for, say 8 to ten seconds starting midway beyond the peak exhale FR and the associated FL is often a slinglet a minute away from any other FL. The attachment is one gone bad, and those like it and worse show up too, mostly noticed as isolated singles too, though also present in disordered crowds [attachment=36441] RE: wildly jagged flow rate curves -- do you see this in your data? - Geer1 - 10-16-2021 2SleepBeta, I am pretty sure that example you posted was a micro arousal (potentially a RERA due to the flow limitation present) just as starting exhalation. Imo it was a quick deep recovery breath that overfilled lungs and that is reason for the following large fast exhale. You probably notice this at elevation due to the lower oxygen content and your flow limitations causing more arousals then when at lower elevations. RE: wildly jagged flow rate curves -- do you see this in your data? - 2SleepBetta - 10-16-2021 Yes, Cathy, the middle or "3rd quarter" of that view you mentioned is a case all its own. Your diverse runs of cycling but distinctly different repeating wave deformations suggest to me distinct lateral vs. supine OA differences along with your acknowledged OA's chin tucking sensitivity. I can't recall you writing much about that. My observations and work suggests one positioning configuration, a sweet spot, cuts your work of breathing a lot; accordingly far more rounded wave tips should be evident there. The work I've done on your inspiration time and duty cycle (data: your dropbox BRP file) shows dramatic changes of duty cycle, starting near 0.8, continuing there, dropping to near 0.5 for a long period and then returning to the near 0.8. The 0.8 runs are gappy and have lots of 0.5 interleaved within them but the 0.5 run is clean. The differences in the overall view, which I believe are accurate, are so stark I've wanted to get additional zoomed in Oscar I and E printouts from you to compare all before posting. If much longer expiration time and lower RR (with less dead space effect) do not accompany the 0.5 level, something is wrong, because gross Ti does not change a lot, though it is grassy. Anyway, sources vary on the normal duty cycle ratios. I've seen 0.3 cited for sleep and 0.4 for wake, as well as a straight 0.4 as the typical Ti/Total ratio. Member SevereApnea posted relevant links here, Could a Fractured Hyoid Cause Epiglottis Prolapse=OSAS | Apnea Board, a paper identifying and ranking airway sites where collapse causes a signature waveform deformity and here, How to stop rolling onto my back? | Apnea Board, a paper connecting sleeping position to patency of pharyngeal sites and their collapse in lateral or supine sleep. A snippet cannot be separated from SA's first linked item so here is the piece URL where the last half of the second paragraph makes the points I intended: Flow-Identified Site of Collapse During Drug-Induced Sleep Endoscopy - CHEST (chestnet.org) That last half speaks to my previous comment about the quick drop from peak inspiratory flow, too little dwell time to increase your TV and have/utilize your most normal longer inspiration time. Again, this line of thought is offered as one possible puzzle piece, the NED -like spots, not the whole thing. Here's a third link you might look at. I suggest it mainly because the word "paradoxical" is central in this paper about breathing and vocalization disturbances, which I'm guessing might apply to your sleep, not to you awake as a singer: Laryngeal and respiratory patterns in patients with paradoxical vocal fold motion | Elsevier Enhanced Reader I'd prefer to keep my hi-jack-like stuff out of your thread and be thinking about and commenting on your graphs. Your case deep rips lots of rich, new and old fL and FL ground. As you know, mixing metaphors, I'm at the other end of that "big picture" pole, wanting to look at and ponder "those little squiggles" with super close up zooms (when I don't have data, time, immediate skills or brains to tool up and digest the data). My eyes and 32" TV screen's 1080 resolution just aren't good enough for me to scan at 30k ft, though I like to see the all-in view, too. But as an older near-brother from Estonia did say, people in hell want ice water. Right or wrong, my thought is that reading the entrails of FR waves for patterns at transitions and what their associations are will unravel most mysteries. However, we can't get more juice out of the data or its curves if it isn't there or can't even be there because of intrinsic limitations, known and unknown. @Geer1: A look at other similar instances with dips below zero indicated a slight mismatching of peak mask pressure relative to the mini-FR-drops' start times, peak pressures being about 0.2 seconds early within 1.6 to 1.8 sec Ti's. In my attachment that early peak is at the forward edge, the "cusp" (the short-radius turn), of the chair/"m" seat as is true in some other instances, some not near FLG but with flow limitation evident in tips. Preceding and following those sighs gone bad, there are continual, runs of varying chairs and low to moderate m-tips. My 300 ft elevation is not a factor. That accompanying short small leak is typical at half-?-my sighs (with P-10, too, though this is from FFM days). Head must bob a bit at the sharp, out of pattern FR changes of sighs, which half-?-the time evoke a small FLG. Just earlier than was shown there were three prominent chairs that triggered the two stepped FL we see ending there too. RE: wildly jagged flow rate curves -- do you see this in your data? - cathyf - 10-17-2021 I think I found some nomenclature in the literature -- this might be called the "sawtooth sign". Or "upper airway fluttering". Or maybe not. I can't find a really good definition of these things (most articles I can find abstract but not full texts...) These discussions are measuring it on the flow volume curve rather than the flow rate curve. (Somebody needs to tell these researchers that a picture is worth a thousand words, LOL) And I've been playing with some OSCAR pictures from last month. I created 2-minute resolution snapshots, and then glued them together into a verrrrrrrrrry long "strip" that shows change over time. I started each strip before the fluttering starts, and continued through until after it ends, to show context. First, some whole night shots from 9/10, 9/15, 9/17: https://www.dropbox.com/s/900eidooz98z2yj/20210910wholeNight.png?dl=0 https://www.dropbox.com/s/o8wszekus6kbtco/20210915wholeNight.png?dl=0 https://www.dropbox.com/s/l9sjwelz0i48kl2/20210917wholeNight.png?dl=0 Here are my "strips" -- three PDFs, should be high resolution. (They are BIG files, LOL) https://www.dropbox.com/s/8ndrhubva9s5crx/20210910.pdf?dl=0 https://www.dropbox.com/s/moauu8eoxos25ea/20210915.pdf?dl=0 https://www.dropbox.com/s/tabqmf18o7i99g1/20210917.pdf?dl=0 What's striking is that this isn't a few wonky breaths -- it's not seconds, it's minutes, and often more like an hour or even more. And it's goosing my heart rate -- you can see it on the pulse-ox graphs... I'm still wondering if anybody but me, 2SB, & elliotg are seeing these spells, or at least seeing them more than rarely. I know that the AB protocol is not to hijack other people's threads, but I'm really looking to see other people pictures to see if I can get some insight into this that I might be missing. I am also leery of generalizing too much off of my one-person experience. And I have in the back of my head that maybe there is some phenomenon in FFM use where inflating and deflating the cheeks, opening and closing the mouth, causes the pressure measurement at the other end of the hose to bounce around because the whole system is continually changing shape and volume in a way that's totally independent of the breathing rhythm. (technical note -- you probably need to download those files and view them in one of your computer's image viewers with some serious zoom and scrolling. The images are 5 inches tall by 25-30 feet long.) RE: wildly jagged flow rate curves -- do you see this in your data? - cathyf - 10-17-2021 Oh, and some context -- I can fix this. Here's last night, vauto, cervical collar, first the full night, then showing the spot where the respiration rate jumps a bit. That's a single isolated breath doing something weird -- totally harmless! https://www.dropbox.com/s/cscp0to30tazgtn/20211016vauto.png?dl=0 https://www.dropbox.com/s/9zgqdi6gixg4kti/20211016vautoZoom.png?dl=0 RE: wildly jagged flow rate curves -- do you see this in your data? - cathyf - 10-17-2021 2SB -- I'm slowly reading through and digesting the links that you published -- thank you! I wish I could get a handle on what the flow-rate curve measurements mean about what physical process is happening in my airway during these periods where the flow-rate curve is fluttering. Does anybody know about the belts used in sleep studies, and whether they are able to detect paradoxical breathing? After looking through the technical addendum to my sleep studies, I can find nothing that mentions that they might look for this in the data. I'm trying to decide whether I should send a MyAir message to Dr SelfImportant and ask for them to evaluate the flow-rate tracings in my two sleep studies looking for flutter, and looking at heart rate data, and looking for signs of thoracic-abdominal asynchronous effort from the effort belts and seeing if there is something going on during the flutter. |