Apnea Board Forum - CPAP | Sleep Apnea
Maybe I have apnea, maybe not, are all sleep doc jerks? - 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: Maybe I have apnea, maybe not, are all sleep doc jerks? (/Thread-Maybe-I-have-apnea-maybe-not-are-all-sleep-doc-jerks)

Pages: 1 2 3 4 5 6 7 8 9


Maybe I have apnea, maybe not, are all sleep doc jerks? - cathyf - 03-26-2021

Background...

Diagnosed with "moderately severe obstructive sleep apnea with associated hypoxemia and sleep disruption (minimum SpO2 80%)" back in 2014. Got an A10, had the usual adventures of mask fit, figuring out settings, etc. but settled in successfully. In 2015 I started losing weight, and over 18 months lost 130 lbs which I have kept off.

Last fall I had a bunch of health things happen, and blew through my out-of-pocket maximum on insurance, and so I decided to try to see if I could get a new machine, as this one has a lot of hours on it. My PA sent me for a sleep study, which was a pretty ugly restless night. Then two weeks later my PA calls me to say that she just got the report back from the sleep center, and their conclusion is that I don't have apnea and am cured!

To say I was shocked is an understatement! My PA asked me if I would like a referral to talk to the sleep center neurologist, and I said yes, but it was 4 more months before that happened.

Here's the narrative of the sleep study data
[attachment=31054]
[attachment=31055]

For the next couple of weeks I tried my own form of sleep study. I set the pressures way down and looked at my data. First I set the min/max to 7/8, then 5/6. And sure enough, no events.

Except for one day, which looked like this:
[attachment=31053]
I was puzzled, but it didn't happen again, so I didn't really know what to make of it. I stopped using the CPAP.

I also suffer from carpal tunnel syndrome (like 80% of all women...) and it's mostly when I'm asleep. I did some research on what I could do to help this, and found the advice to not sleep on your side, but only on your back.

*bing**bing**bing**bing**bing* bells went off!!!

(I've used up my 3 attachments, so I'll continue in a new reply)


RE: Maybe I have apnea, maybe not, are all sleep doc jerks? - cathyf - 03-26-2021

(Continued with some more attachments)

One of the things I noticed on both this sleep study and the 2014 study is that my AHI supine was MUCH higher. I've always hated sleeping on my back, and was surprised that I was even on my back at all during the sleep studies. I had picked up on the "RDI supine of 26" in the latest sleep study. In that study I had one cluster of events during the short time I was on my back and one cluster later in the night in REM sleep. (In the 2014 study I had a nonREM AHI of 9 and a REM AHI of 45. Supine #events 23, AHI 19, Side #events 68, AHI 14.)

So next experiment was to strap on the mask and set the machine wide open, and deliberately try to sleep on my back. Whoa baby!

[attachment=31057]

Ok, to back up here, one of my ongoing puzzlements with CPAP all along is that I always have a boatload of flow limitations when I am asleep. The machine will chase those limitations up to whereever I set the maximum, but it doesn't appear that -- in my case -- flow limitations are any sort of harbinger of impending apneas.

[attachment=31058]

If I set the max to a place where I don't allow it to raise the pressure, it pegs to the max all night, but no apneas. (ok, no apneas as long as I stay on my side.)
[attachment=31059]

In the last 2 weeks all of this is falling into place.
-- I clearly had apnea back when I was heavy, and my sleep was a lot better on CPAP, but it's still never been great. I continued to have lots of daytime sleepiness, I sometimes have to pull over when driving, doze off at the dinner table, etc.
-- I've always had a crazy Flow Limit graph, but very few events.

So here's where I'm going...

- I'm wondering if I have UARS and always have.

- I clearly had positional apnea all along, and I think I still do.

- I'm thinking that the weight loss did successfully cure the apnea that I was having when I was sleeping on my side.

I finally had the consult with the sleep specialist a week ago. He was pretty much a jerk, but did schedule me for a new sleep study, where I'm going to deliberately sleep on my back.

I have a somewhat complicated medical life, in that I suffer from psoriatic arthritis, and it's progressing, and it's attacking my right wrist. I also have the carpal tunnel, and the inflammation from the arthritis seems to be making it worse. So I can't just go with "don't sleep on your back" (the old joke, "doc, it hurts when I do this!" "so don't do it!") And my experience with carpal tunnel is that waking up in agony is just as much a sleep wrecker as apnea is!

So I am trying to figure out where I am, and what I should do...

Any wisdom greatly appreciated!


RE: Maybe I have apnea, maybe not, are all sleep doc jerks? - Gideon - 03-26-2021

See the clusters of obstructive events on 22 mar and Nov 2020 ? That is most likely positional apnea caused by cervical alignment or a chin tucking, No CPAP and no amount of pressure will correct that. Because it occurs so infrequently just be aware. Of it. The'fix' is a typically pillow change or a soft cervical collar. For awareness read the cervical collar link in my signature. I doubt any of your doctor's are aware of this enough to recognize it.

I don't see enough to confirm UARS. The diagnosis of UARS via a sleep study is made by seeing high RDI and a low AHI. REARs are a series of flow limits ending in arousal.

Your sleep study had a number of arousals that were not determined to be respiratory in nature, what were they?

I suggest moving the flow limit chart up to just below the flow rate chart, then zoom in to a 3-5 minute view so you can see the waveform clearly then scan looking for arousals. These are typically a larger breath often accompanied by uneven breathing. You are looking for RERAs. Count them.

The number of flow limits you have is IMHO enough to disrupt your sleep. I am going to suggest that your next machine be a BiLevel, specifically the ResMed AirCurve 10 VAuto. Pressure support is what is used to treat flow limits and a BiLevel allows much higher levels of pressure support and in much finer increments than your current machine (EPR).
I'll leave it to others on how to force sleeping on your back.

I'm pretty sure one of the sleep devices compatible with OSCAR monitors sleep position, if I'm wrong consider recording your sleep on camera to determine sleep position.
This is in support of your need to sleep on your back.


RE: Maybe I have apnea, maybe not, are all sleep doc jerks? - cathyf - 03-26-2021

Thanks for the quick reply, Gideon!


I'd ask everyone to bear with me here... Part of my problem is that I've been connecting all sorts of new dots in the last two weeks, but I'm also realizing that all sorts of connections that I made in the past are simply wrong! Getting that all sorted out is not easy. I got my CPAP machine in Oct 2014, and started losing weight in Jan 2015, so most of my use of the machine has been post-weight-loss. Since the very beginning I've had few events, and I took that as meaning that the therapy was working. My experimentation with lowering pressures has been about the fact that my original F20 mask started to wear an ulcer at the bridge of my nose, so I had to lower the pressures to loosen the mask. So it's not really clear at all when I went from not having events because the machine is working to not having events because my non-positional apnea is cured.

First off, I noticed as a child that when I'm sleepy and I'm on my back, I have this compulsion to roll to my side -- I'm just not comfortable on my back. Up until now I just assumed that meant that if I were to roll onto my back while asleep, I would roll back onto one side or another automatically. Which is of course stupid to assume! Just today I made a connection: before I was diagnosed, I remember that I would wake up, and I would have to sit up in bed because there just didn't seem to be enough air down there at the top of the mattress. I realized today that I'm remembering waking up on my back! And I'm looking at my 2014 sleep study, which shows Supine #events=23/AHI=19, and Side #event=68/AHI=14. Doing the math, I spent one hour and 13 minutes of my six-hour sleep study on my back. So 20% in 2014, vs 7% in 2020. So much for "I don't have to worry about positional apnea because I never sleep on my back." I've been worrying about this because of my carpal tunnel maybe forcing me to sleep on my back, but now I'm realizing that the problem is that when I'm asleep I'm not in control of what I do.

Next connected dot... I started using an Amara view mask in April 2016, at the end of my 130lbs weight loss. I  switched to a dreamwear mask when they came out. Because of the shape of my now-thinner face, the dreamwear and the view both leak like crazy when I'm on my back. When I'm awake, that's another thing that forces me onto my side. I used an F30 during a mask study in fall 2019, and I liked the mask because it fits better than the Amara/dreamwear. But I decided I really didn't like it more because of the hose connection being on the mask rather than the headgear. Ok, when I started 2 weeks ago to do my own experiments of sleeping deliberately on my back, I realized that the dreamwear won't work on my back so I broke out the F30 again and have been using it. But I've always had what few events I've had associated with with giant leaks, and I was assuming that the event detection during big leaks wasn't reliable, and I wasn't getting enough pressure because of the leaks, when I now think what was really happening was that I would roll on my back and the mask would leak AND my airway would collapse into crazy flow limitations AND I have apneas, and that all of those things were caused by my position and the machine was measuring accurately.

Looking over my sleep data from the last 6-1/2 years, I realize that one thing is constant: as long as I'm awake, my flow limitations are really zero. The instant that I'm asleep, they take off. They drop back to zero when I wake up. Now there are LOTS of zeros sprinkled in the data when I'm asleep
[attachment=31070]
but I'm thinking that this is actually a weakness in the way that the machine treats the flow limitations -- if you look at what's going on in that 1:02:45 - 1:05 flat area, and then look at the flow rate, FL's & snore,
[attachment=31069]
then it's pretty hard to argue "nothing to see here" between 1:02:50 and 1:03:30!

My experience is that I feel like I must start breathing through my mouth when I start to get drowsy. So much so that if I'm lying in bed with my mouth closed, comfortably breathing through my nose, then I know I'm not going to sleep any time soon and am headed for perhaps hours of insomnia. I think this is the onset of flow-limited breathing, happening when I am still awake enough to be aware of it -- and looking at graphs later I think that's the right interpretation of the timing, and the machine is recording and measuring this. Also, when I'm stubbornly trying to hold my mouth closed to see if I can fall asleep with it closed it feels like I'm holding my breath and when I give up the fight I pop out a big exhale not inhale. Which matches up with what you are saying about the EPR and bi-level -- the "limitation" of a flow limitation is more on the exhale than the inhale.

Periodically over the years I've tried a couple of experiments. One night I will set the min/max pressure very low. The machine measures the flow limitations, cranks up the pressure, and I spend the night "pegged" at whatever the max is with flow limitations bouncing up and down all night. But I don't have events! Then a different night I'll set both min and max pressures high -- and I'll watch the flow limitations bounce up and down, the machine cranks up the pressure in reaction, but the added pressure doesn't stop the flow limitations at high pressure, either!
[attachment=31072]

Another piece of information: in my 2014 sleep study, I had 77 hypopneas (34 NREM, 43 REM) but only 14 apneas (9 NREM, 5 REM). Since I lost the weight, my events are more apneas than hypopneas, although more like 3-2 ratio than 6-1. And whenever I have one of these on-my-back clusters, they are virtually all obstructive, not hypopneas.

The ResMed APAP model is that unopposed flow limitations proceed to apneas & hypopneas, and flow limitations can be fixed by higher pressures. In my personal case, I think that neither of these are true. I think what I'm seeing is:
-- lots of flow limitations when I was fat, lots of flow limitations now that I'm skinny.
-- crazy high apneas when I'm on my back, both fat and skinny
-- lots of hypopneas when I was fat, very few now that I'm skinny
-- pressure does help with events if I'm on my side, but now that I'm skinny I don't have events on my side
-- it's really hard to tell if pressure helps the flow limitations, or the supine apneas. It's definitely not much help.

My next test is to buy a cervical collar at the Walgreen's. I was going to do research and measuring and find one online, because Walgreens only has one size, but it's only $15 and I can get it now and worry about size and online if the Walgreen's model doesn't fit.


Thanks again, anybody who is reading this far. It's been kind of a crazy ride, and writing it all out has really helped me see where I've been going wrong all along...


RE: Maybe I have apnea, maybe not, are all sleep doc jerks? - Sleeprider - 03-26-2021

I'm going to disagree with Gideon's assessment to the extent that your flow limitation is clearly characteristic of UARS or a high degree of airway resistance. Your 95% flow limit is routinely over and index of 0.4 which means if we zoom into the respiratory flow rate we are going to see a lot of flattened and downward-sloping inspiratory peaks. The fact these don't result in hypopnea or RERA being flagged is surprising, but shows mostly that your respiratory volume stays fairly steady and flow reductions do not meet the criteria for a hypopnea. Proof of my theory is that your inspiration times are far longer than expiration time which is completely backwards. You are sucking air through a narrow straw and expending a lot of effort to do it. You have adapted to this situation and don't have apnea events but you have tremendously impaired respiration.

If you want to go into the weeds on this huge flow limitation you have, then show us some closeup zooms of your flow rate chart. Especially where flow limitation is relatively high, I expect to see extremely distorted respiration with very long inspiration times. Instructions for getting a zoomed screenshot are in the Organizing Oscar Charts wiki in my signature links. The clusters of apnea are, as indicated by Gideon, positional apena, and the driver of those clusters is chin-tucking. It is discussed in the Optimizing Therapy wiki here. http://www.apneaboard.com/wiki/index.php/Optimizing_therapy#Positional_Apnea We also describe how to test for this by sitting and relaxing in a chair while allowing your head to sag to your chest. It will block or occlude your airway if you're prone to this problem.

Your CPAP can help you with the flow limitation problem if you turn on EPR (exhale pressure relief) full time to a setting of 3, and increase the minimum pressure to allow for that exhale flow reduction. You will need a minimum pressure of 8.0 and maximum pressure of about 12 to use EPR to best effect. I anticipate that with as serious as your flow limitation is, you will end up wanting a bilevel to fully compensate for the airway resistance. What we are looking to achieve is to drive down inspiration time by using pressure support (the pressure increase from exhale to inhale) to help supplement your physical effort to suck in air. This will result in much more comfortable breathting and less physical exertion to breathe. No wonder you are so tired. Your sleep doctors are clueless about this because they are apnea bean-counters. They need to look beyond the AHI and see how impaired your breathing is. It is certainly functional, but this disorder is exhausting.


RE: Maybe I have apnea, maybe not, are all sleep doc jerks? - cathyf - 03-26-2021

Ok, first of all, I'm absolutely convinced that I have positional apnea from chin tucking -- my amazement is more that it took me this long to figure out something this obvious!


I'm going to post a series of zoomed-in pictures, and since the board software limits me to 3 attachments per post this is going to be fragmented across several posts. When I get to the total end I'll put something at the end of that post.

This is the sequence of events... 
[attachment=31073]
Nov 11th was my sleep study. Nov 22nd my PA called me and told me I was cured of apnea. My reaction was to set the pressures on my machine way down and start looking closely at the data. As you can see from the Overviews, except for Nov 27th, that sure doesn't look like data from a person who still has moderately severe sleep apnea.

I'm going to focus on two dates, Nov 26th & 27th. The 27th was the night that I had a 25-minute apnea sh**show starting about 30 minutes into the night, and then a couple shorter ones a little later. I think I must have been on my back. What's also interesting is that there is a flow limit catastrophe that starts basically as soon as I fell asleep and actually tamped down some when the apneas hit. The difference between the first and second half hour is the other point that I've been harping on, which is that when the breathing waveform gets really turbulent the machine records a zero for the flow limit score, but I think that's a different sort of zero from the "not flow limited" zero. I think it merely represents a region where the "flow limitation maths" don't apply. So I don't think that it's correct to say that during the first half hour when I had 2 hypopneas and one OA, that I was MORE flow limited than the second half hour when I had 4 hypopneas and 22 OAs. Although that is what the FL graph seems to say.

Here's the picture, which is an overview of the whole night of the 27th:
[attachment=31077]

And here's the somewhat-zoom of about that hour
[attachment=31078]

...continued in the next post...


RE: Maybe I have apnea, maybe not, are all sleep doc jerks? - cathyf - 03-26-2021

This is the first zoom, from the front end of the whole thing.
[attachment=31079]
That's me breathing, NOT having anything scored as an "event".

really flat on both the inspiration and expiration side.

Here's what's going on 30 minutes later:
[attachment=31080]

Ok, I just realized that the Insp Times go wild during the events, while the Exp. Times don't. Here's that picture from the previous post with the Exp Time y-axis forced to the same 0-16 as the insp Time:
[attachment=31081]

There is a boatload of stuff going on here, and I don't think I understand it.

In the next post I'm going to focus on the previous night, when I had some serious flow limitation phases, but no events to speak of.

....continued in next post...


RE: Maybe I have apnea, maybe not, are all sleep doc jerks? - cathyf - 03-26-2021

Here's the overview of the night of Nov 26th, a much more ho-hum night:
[attachment=31083]

Here's it zoomed in on the end of that 5:30ish flow limit bump:
[attachment=31084]

Ok, so yeah, that's the difference between a flow limit of .34 and a flow limit of .61...

I'll end by saying I think that I've got nasty ugly sleep apnea on my back, but I think I've also got a whole lot of not as nasty flow limitations when I'm on my side.

In the next post, I'll put the graphs from my sleep study

...continued on next post...


RE: Maybe I have apnea, maybe not, are all sleep doc jerks? - cathyf - 03-26-2021

Finally, here are the graphs from my sleep study:
[attachment=31085]
[attachment=31086]

And the data summary:
[attachment=31087]

What I find pretty striking is that the sleep lab view of sleep doesn't seem to have any concept of "flow limitation" in the ResMed sense, and no inkling that I've got that going on pretty much constantly when I'm asleep.

...ok, this is my last post of the series. (I've used 4MB of my allocated attachments so I've also about run out of room!)


RE: Maybe I have apnea, maybe not, are all sleep doc jerks? - Gideon - 03-27-2021

On the 27th you experiencing a form of positional apnea. The tell is the cluster of obstructive events. This is absent on the 25th. This was nearly completely blocking your airway. How often do you see this? This is typically the result of you tucking your chin into your chest. No amount of pressure can fix it. It can be as simple as too many pillows, if not most get relief by wearing a soft cervical collar to prevent the chin from tucking. You had a cluster of RERAs on your sleep test that may have had the same cause.

Your EPR is off. EPR is the best way to treat flow limits with your AutoSet. It will not even touch the positional apnea I mentioned above. Set EPR = 3, full time.