AHI < 1.0 now, but still tired? Is it UARS, RERA, arousals or FL in your FR peaks?

[cathyf]

Justification for suggesting nasal pollows (or my loony imagination?) here: I think the air-tight sealed coupling of a nasal pillow to your nose (nares?), together with no (or minimal) mouth leakage will enhance and maintain steady retention of your airway's effective and critical cross sectional area when supine. Not informed in pneumatics, my sense is that with a full face mask there is more opportunity for variation and shortfall in the critical pressure needed inside the airway as we exhale or inhale through our mouth. Seemingly unrelated, as as any heart aspects are here, we know that our pulse waves travel through airway tissue and its and surrounding tissue and show up in tiny flow rate waves ("cardiogenic ballistic effect"), primarily near the end of expiratory flow (for me, anyway). Somehow our FR has a superimposed pulse wave and I am "supposing" our breathing regularity has a similar effect.

I’ve been thinking exactly this for some time now. Back when I got my A10 in Oct 2014, the DME’s RT had a nasal pillow mask already with my machine when I got there. I put them on and — before even hooking the hose up — I had a bizarre reaction like a panic attack. It felt a lot like how it would feel when I would wake up feeling like I was suffocating. (At that point I had been suffering from untreated apnea for years) So the RT whisked the P10s away and went out and snagged an F10 and I was typecast as needing a FFM forever. 

What I am coming around to— and I think that you are a lot further along this understanding than I am, is that “needing a FFM” is actually the underlying problem that I should be trying to solve! And for me the discovery of the cervical collar is some hope that I could figure out how to sleep in such a way that my airway could stay open enough to breathe through my nose without all of the extra effort. I’m just about to head down to my DME and see if I can get a nasal pillow mask. 

One question— what do you think of the Dreamwear pillow rather than the P10s? Up until two weeks ago I was a dreamwear FFM fan, but the F30 has a whole lot more substance to the cushion and so I get a much better seal. I used to think that I really liked the hose connection and outlet valve on the top of my head, but now I’m figuring out that I may be tucking my chin in order to keep the outlet valve free of pillow, headboard, etc. And I definitely cannot get a good seal on my face with the dreamwear if I’m on my back.

[2SleepBetta]

. . . . . (I could post a reply on that other thread saying to come over here)

cathyf:, 2SB  here,

 Before responding to other matters in your post #21, a few hours ago:

My thread on the Dreem 2 and matters in this thread raised that same thought and question. 

But, for the benefit of your therapy, you would  lose some  helpful contributions from others by mainly posting here. You would lose those who wll not read here, this thread  being "in the weeds" , not of wide interest. I suggest the main body of your treatment matter be posted in your thread and that your more general but closely related findings and conclusions or questions, which could be applicable to many who might come here, be noted here for others as I suggest below.

As mentioned in my OP, this thread 's focus is off  the "SA Treatment'" beaten path and  is stumbling into the shaded woods of, say, UARS, IFL and whether we can spot, score and gainfully use arousal frequency  and more subtle FR-signal changes. If so, we could then , selectively and deliberately, try different single habit and health choices looking for a payoff in more restful sleep. This thread has little to say to help an individual's therapy if it is beyond member-readers' and my limited knowledge or the relevant sources we are aware of.

I know that the rule is “keep your stuff together” but I think that over here is “together” in a different way. 

I agree and do mull over that, too. Let's hope an AneaBoard leader will point the two of us to AB directions or give us one. 

Otherwise, in making a point we or another member made in a post elsewhere, it isn't good use of time and it uses up server capacity to restate or re-illustrate that point. I  suggest --as it has likely  been directed elsewhere,--that we should let our primary sleep concern determine where the post should go or whether a new thread be started or one be continued. When that thread or post  uncovers germane information for another thread we are aware of, then we  would do well to post a reference to our (or to anothers') most on-point post. (Hover over the post number in its upper right corner, copy and paste-in the post's address that will appear and give a paragraph, image or link cue. Do that for the benefit of readers' awareness in that  (or this thread). We won't do that just to  garner clicks and eyes--like so much of what we don't want to see on the web)

This speculation of mine earlier, which I edit here, would have been better as follows:   I think the air-tight sealed coupling of a nasal pillow to your nose (nares?), together with no (or minimal) mouth leakage might will enhance and help maintain steady retention of your airway's effective and critical cross sectional area when supine. 

The idea is a counterintuitive hunch, maybe totally wrong, pressure is everywhere the same at all times with a FFM, right?. But isn't air compressible so any pressure changes will enlarge or shrink the volume of an elastic enclosure; further, with FFM and mouth breathing the enclosed compressible volume of air is much greater than for the P-10 pillows mask . 

If I can find and try my Resmed F-10 full face mask and get it to seal, I  bet "my two bits" AHI and FL will go up significantly; do that FFM test with the continued use of the same  P-10-efficacy benefitting factors (a supine block vs no supine block and, always, using the c-collar). 

Again, for you, as in my case as a former AutoSet user, a user with high levels of FL,I believe the VAuto's higher pressure capability, shorter response time and greater pressure support could cut your flow limits a lot as it has mine. I should have cited it as a major factor among the others, particularly the c-collar, taking my high AHI down. Of course higher pressures and pressure support must be carefully adjusted over time to avoid bringing on Central Apnea and related Hypopnea.

Whether the P-10 would make air passage through your nose less restricted, I expect, depends on whether it is obstructing hard or soft tissue there, vs sleep-slackened tissue elsewhere: tissue which partly surrounds the air channel which could account for a significant part of your restriction. You likely know that the problem is in the nose. If you haven't read at the link Zackio provided, I suggest you do so. It discusses the etiology of many of our breathing problems, often going back to stuffed-up noses as kids and how we burn our recovery bridges through our unknowing years of disordered breathing in sleep..

Re Dreamweaver, I am not familiar with any masks other than those mentioned in my bio. The P-10, light as it is and with its minimal sealing perimeter and skin contour differences to bridge, is far and away best for me and many. The bleep mask does almost as well, but with less sensitive aging fingers, it takes more fussing with it and, further, its daily replacements needs make it more expensive. I think having least perimeter and countour variations to seal and bridge are the key factors in favor of nasal pillows. For those the P-10 is great. The Brevida and Wisp worked much better for me than the F-10 and Simplus FFMs and the Amara View hybrid.

If you go back to your thread to continue to work for solutions, please post key links here so all concerned can follow your general findings on your related matter.

[cathyf]

This is something that I think is significant... Look at this night here:
[attachment=31333]

I'm NOT interested in the small ugly clusters -- I know how to get rid of them -- wear a cervical collar. What I'm interested in are the extended short sections of the Flow Rate graph. I'm focused specifically between that last hypopnea at 3:20 and the OA at 3:40 which starts the next cluster. Then look at the FLs underneath -- I think that's the breathing through the half-kinked-straw look.

Next I'll show 4 closeups across the whole 20-minute band:
[attachment=31334]
[attachment=31335]

(next two attachments in the next post)

[cathyf]

...moving across...

[attachment=31340]

...and now we plunge in to the next event cluster:
[attachment=31341]

It's almost as if I spent 20 minutes just enduring, not struggling, not fighting, just breathing through my kinked straw.

This last picture is after I came home from my sleep study. I strapped on the cervical collar, strapped on the mask, and went for a couple more hours of sleep. There are long stretches of "pinched" looking breathing.

[attachment=31338]

[2SleepBetta]

No penetrating analysis here, just guesses.

One stab at it:.

After looking at your most recent set of images, it seems to me, for your first image, that your clusters and some individual apneas mark alternating beginnings and endings of periods when the airflow characteristics and obstructions change, for a time, and remain that way until the next cluster or apnea or cluster. 

To me that set of changes signal  either a positional factor (the result of a head or bodily change of rotational or elevational position) or looks like the effect of some level of obstructing chin tucking.

When you came back and caught more sleep, were you lying on the same bed or sleeping in a recliner, unlike your sleep situation that presented the clusters?

Another stab, not much different:

You might have, for a simple example, three different bodily, head or chin tuck postures you go to and remain still in for sleep segments. One posture where FL are lowest, a second one where FL are high and more irregular, if not nearly constantly high, as for a time in one of your graphs, and, a third one where clusters explode. The latter wakes you up sufficiently to change to one of the other positions for a time. Then after being still for a time, you go back to the cluster causing posture, orientation or tucking.

Other:

Your first two zooms in the current set of images indicate nearly continuously high FL along with a low amplitude FR curve: both telling me, along with the curve flattening, that you are doing a lot of work to draw breath through your straw. But you are physically able and get enough O2 to do it fairly constantly for long periods during those periods of low amplitude FR (i.e., periods of highly restricted airflow).

At first the relatively constant level of FL bar graph in images 2 and 3, one particularly, jarred me because the FR curve amplitudes and shapes seemed so even and and consistent that it appeared to falsify what I claimed was true of FL. But I looked more closely at irregular shaped peaks of the inspiratory flow in the more enlarged view. The shapes of individual and near-neighbor FR waves vs. the corresponding levels and changes in the height of the continuous FL graph did satisfy me that  it made sense and I had it right. It is because very minor changes of shape at or near the peak air inflow rate have a highly magnified effect on incoming air volume. In my case, a single "M" curve tip very often is followed by a small FL within the time span of the next inhalation and all that can be within a period of minutes when there were no other flagged FL.

I don't recall you mentioning that your Fitbit shows or records positions. As I believe others have suggested, I recommend you video your sleep or get a wearable accelerometer device
that will give you a time and position view of your sleep. Also, can your bed partner offer any information on different breathing sounds or positions?

I will step away from this for a time and hope others can be more helpful than my guesses. Gotta get busy working up my taxes and have had some material nearly ready to post here after long delay. Meanwhile, good luck and let us know of findings.

[2SleepBetta]

Picking up from where I left off, above, it was good to have cathyf post thought provoking questions, examples and thoughts here. Appropriately, for her benefit, she has taken her further work to her own therapy thread and has posted in yet another thread on summarizing flow limits, as started by  sheepless.  The inconclusive, matters regarding flow limits (FL) I post next, here, have long simmered in my mind and were first intended for posting in one of those threads, but they fit better here with the general topic of FL effects. 

If anyone can weigh in on exactly what a Resmed flow limit flag means, the bases of its scale number assignment and duration and its positioning on the OSCAR timeline, please do so. Also, everyone is welcome to comment, ask questions and call attention to errors. 

The ApneaBoard wikis http://www.apneaboard.com/wiki/index.php...ome_(UARS) , http://www.apneaboard.com/wiki/index.php...limitation , and http://www.apneaboard.com/wiki/index.php..._and_BiPAP are good sources of valuable information about flow limits and treatment for them. Similarly, links at the beginning of this thread point to a wealth of information. But I am unaware of anything other than ResMed patent applications that go deep and may fully explain what a FL flag means when noted by the machine (VAuto) at my bedside.

Simply put, my understanding is that if one had a continuous, unvarying level of FL, then the machine would not flag any FL. The reason is that the machine (with its detection algorithm) only responds to and flags certain changes in our airway pressures and related airflow. Again, the question is, what exactly causes our FL flag "to be thrown" and what is the meaning of the flag height and width as well as its positioning on the time line.

cathyf's and others' comments prompted my (and others') questions whether the flag dimensions convey the amount of airflow (volume) reduction that was caused by airway obstruction. To check that I had to buck up and learn how to delve into the huge files--data are recorded 25 times per second--the machine generates each sleep session. The bare bones needed to start were in data from which OSCAR creates the flow rate (FR)  curve and FL flags. That info in hand, I could then determine air volume delivery for periods of inspiratory flow, no matter what shape those waves had. Then, with FL plotted on the same timelline, I expected to gain a better understanding of what FL meant to inspiratory flow. 

I picked a simple starting point, a lone M-tipped inspiratory wave, a flow limiited one, that was amid many uniform and most normal waves. That moderately deformed wave delivered 11% less air volume than its predecessors. Most of my "lonelier" M-tipped waves--those not in a crowd of such waves--are followed by the start of a small FL, say .02 high by 8-10 seconds. Hmmm. 11% and .02 x 10? Any correlation? Many more FL needed to be assessed that way. 

But the volume of data and tedium of putting it together in an Excel spreadsheet is daunting. Anyway, forced to pare down the example, I ended with the "too busy" attachment, for now. Larger excerpts to follow. I wanted to show all the key flow related metrics at once--all squeezed to show just their full height range..
.
Please offer suggestions how to get a grip on the task and  offer comment on how the set of graphic depictions of breathing metrics relate among themselves.

   

Section "A" is all that is new here. Each segment represents 5 seconds of flow time, the height represents the total area under that inspiratory FR curve cycle. If the Resmeds used a 5-second sliding window, the depiction is as if a snapshot were taken every five seconds and were placed in a continuous, non-overapping string as here. The green colored rectangles call attention to the highest and lowest flow volumes and how the other metrics below relate to those extremes. 

Section "B" was created by charting the ResMed "BRP" data file and then summing up the areas of the (.04-second-wide) X (data-value-height) vertical strips. It is presented only to show it (this representation of volume, not rate) agrees, as expected, with OSCAR's presentation of FR and, therefore, it supports the indicated filling of the 5-second buckets.

Section "C" shows some M-tips are FL flagged and some not. Why the difference? Good question. A FL frequently follows an M-tip during its exhale, about mid exhale.

Section "D" shows that all the sleep variables shown below the FR curve changed the most during the periods of FL.


The graphic is too busy squeezing too much into one view, but I wanted to show all of them in relation to each other. Worse the file had to be shrunk to be attached  and cause eye strain here, but I think it it gives some idea of how to proceed. Unfortunately, it all raises more questions and offers no immediate help. For example, the right-most rectangle shows ia dip in volume delivered (in B) but it has the most filled bucket (in A).

[sheepless]

2SB, interesting but necessarily beyond the effort required for me to constructively participate so I have nothing to offer except plenty of interest and moral support. keep digging!

[cathyf]

2SB -- I'm looking at your OSCAR graphs and my OSCAR graphs. Yours I see these little quirky things going on. Mine looks more like the ResMed algorithm's worst nightmare. I look at the shape of my FR curve, and then what the machine calculated for an FL value, and I can almost hear the machine muttering "WTF?!?"

[attachment=31692]
This first picture is from 3 years ago (April 2, 2018). It shows 30 minutes in three sequential 10-minute zooms. The first 10 minutes, I'm rumbling along, with what (for me, anyway) are minimal flow limitations. Mostly below 0.10. What's striking is that the flow rate on the exhale is SO much faster than on the inhale. Then we get to ~2:36 and struggle for a couple of breaths and then crash into a 27-second OA, followed by a 39-second OA, and then a 5-second OA. (Which is puzzling, since I thought OAs had to be at least 10 seconds?) But then the next 12 minutes get really wild, where I am going minutes at a time with FLs up near 1. Then a micro arousal, and things settle back into what -- to my eye -- really looks a lot like the first 9-10 minutes, but the machine doesn't score the FLs nearly the same.

This next picture is a 5-minute zoom out of the middle of that ~12 minutes where the flow limit curve looks like a city skyline with skyscrapers.
[attachment=31693]
(My max flow limit that night is 0.87 and the 95% is 0.54. This is one segment where I'm heavily there.)
It's pictures like that which make me mutter "sine wave? what sine wave?!?"

Ok, enough ancient history. The next picture is four 10-minute sections from last night.
[attachment=31694]
First look at the middle two segments (5:30-5:52) This is one of those examples where I think maybe the algorithm is overwhelmed. Look at the area around 5:44-5:47 where the machine is scoring that at minimal or zero FLs, compared to 5:47:20-5:49:10 which really looks a lot healthier. I'm seeing that there is this distinction between the machine scoring a section as zero or minimal FL because the breaths look pretty good, vs other regions where I think the machine is scoring a zero because it has simply given up.

Now, a different comparison, which is the top line (5am-5:10) compared to the bottom line (6:07-6:16). I am completely mystified as to why that top line is scored as virtually no flow limits, and the bottom is a long significant flow limit. Ok it's not 0.87, but it's a sustained 0.2-0.3 without dropping to zero at all.

When I look at my data in some places I think I'm understanding what's happening, and then I look at another time slice which just leaves me puzzled.

[2SleepBetta]

Hi cathyf,

Having to hit the sack for a meeting in the early AM, just one quick response for now, upon dropping by. 

This is my strong first impression--right or wrong--of your 5-minute zoom (your second image block). I scanned it but need to read all more carefully, especially below those 5 minutes, including your lower graphs.

I think the 5-minute view shouts that as you labor to breathe in,  as you seem to labor, its like your rush of air inflow quickly slams a tissue door or flap in your airway closed, much like house doors at inflows slam closed when wind drives air inward and through the house and out another leeward open door (which might well close too to if free to do so). 

It's the same effect an airplane wing lift comes from, differing pressures on each side of a solid member in the airstream. Your flap or sleep slackened tissue (sleep slackens airway muscles, most all muscles) relaxes or collapses and the vacuum causes the airway to be pinched closed--all that being triggered by the work and airway vacuum as you inhale.

Later

2SB

[2SleepBetta]

The link below is to an updating correction or refinement of the following italicized quote from my post #26 above:

"I picked a simple starting point, a lone M-tipped inspiratory wave, a flow limiited one, that was amid many uniform and most normal waves. That moderately deformed wave delivered 11% less air volume than its predecessors." 

http://www.apneaboard.com/forums/Thread-...#pid392104


The 11% value was based on more inspiratory  flows than Resmed's algorithm factors into FL variation flags. At the link the flows and flow areas are shown. Looking at only five and two flows preceding the M-tip, the reductions, respectively, were 8.4 and 7.8 percent, not 11%. As further explained at the linked post, no inerpolations were done because the error for omitting them was estmated to be less than 0.4%,