Extended high flow limits -- what process is going on?

[Geer1]

Your flow limitations are real. The reductions in flow rate are also real and the example you posted ends in arousal and recovery breaths. Reviewing some of your other threads/data flow limitations usually appear to be real and appear to commonly be associated with RERA's.

The sleep study I saw in other thread must be different then the one you are referencing. There were almost no breathing events in it (the Nov 2020 study) so I figured rem wasn't present in that study. It sounds like your flow limitations are much worse in supine position which makes sense.

If you are willing to buy a vauto out of pocket I would do it, it is the best machine for treating these flow restrictions. You will never treat them with APAP and will have trouble convincing a doctor that anything is wrong (only thing that would get flagged if you had a titration study is RERA's and they might not even occur often enough for them to think they are a serious issue although my guess is your bigger issue is respiratory effort because of the flow restrictions).

[Sleeprider]

With flow limitations, the Resmed algorithm aggressively increases pressure in the Autoset Standard algorithm. This pressure increase has diminishing returns in terms of efficacy in the treatment of FL. Keep in mind, the algorithm works under the presumption that increases in FL are an indicator of increasing obstruction and possible apnea. In your case, you simply do not have the apnea, and continue to breathe with greater effort. It is pressure support that more effectively treats flow limitation by supplementing inspiratory effort with higher positive pressure during inspiration. The limitation of the Vauto pressure support is that it is only triggered when spontaneous effort is present. In your case that seems not to be a problem. The Vauto is capable of CPAP, VPAP S and VPAP-Auto modes. I'm sure you will find the pressure support is very helpful in making your sleep more comfortable and reduces arousals associated with flow limitation and respiratory effort. That said, we don't understand the mechanisms of your particular flow limitation / airway resistance, or why it seems to appear intermittently.

[Geer1]

Intermittent nature is probably a mixture of supine and rem as both seem to have been factors in sleep studies. Maybe another positional aspect or issues with nasal congestion etc worsening it on some nights like this one.

[happydreams]

Getting the insurance/medical establishment to buy you VAuto, in my opinion, would be an exercise in frustration, and would take a long time.  You would need to build a case for it.  Insurance companies treat to AHI=5, so you need to make a bullet proof case.  There are some stories,of success here, getting better machines, but the easy path is to not play the insurance companies game of stalling and pretended ignorance.  If your have read many threads here, there are a lot of them about people struggling to get insurance to pay.

If you have the means to do it, just get a used VAuto.  They are not that expensive.  Spare yourself the aggravation and instead give yourself the opportunity to better treat yourself sooner, rather than later or not at all.  I decided one day that I didn't have to go on feeling bad anymore and did something about it, and bought one second hand.

I feel so much better now with the VAuto, that I just posted in the success story section.  My titration wasn't as fast as I would have liked, I floundered about a bit until I started using statistics and data smoothing, but I got there.  Effective treatment is life changing.  You deserve to wake up early in the morning with a huge smile across your face and say "I feel good today!"  Won't lie and say every morning is like that, but many days are like that now.  Before effective treatment, I would have 3 good days in a YEAR and many hundreds of bad days.  It has been a big turnaround.  

I feel like a cheerleader now, but, if you can, just do it.

[cathyf]

Well that's kind of a turd in the punchbowl! I realized that I can't use a nasal mask with pressures above 8 or so.

For the last couple of weeks I've been running my APAP at sub-therapy pressures to collect data. One of the data points I've been exploring is the question of whether I can keep my mouth shut without a lot of pressure with just the cervical collar, so I've been (successfully) using a nasal mask with pressures of min=7 max=8 and EPR=3. And it's been fine -- no more than the occasional minor leak.

So last night I decided to set my machine back to 7-15 to see what would happen with the flow limits. I'm using a dreamwear nasal mask, and as you can see as soon as the pressure rises it just blows the mask right off my face all night.

  8Jun2021OSCARhi.pdf (Size: 666.91 KB / Downloads: 15)

And that's pretty much how I remember it -- constantly waking up trying to make the sound of rushing winds go away!

I'm thinking that I'm back at full-face mask from now on...

Ok, so here's where I think I stand:

1. I have severe positional apnea. Pressure is irrelevant and the machine is useless against it, but it is completely controlled with my $12 cervical collar. Without the collar the machine pegs at 20 and simply records apnea after apnea -- clusters where I will spend 35-40% of the time not breathing. I get significant desats -- into the upper 80s. With the collar I get a random occasional bit of sleep/wake junk, but otherwise no events.
   
2. For me, asleep=flowLimits and noFlowLimits=awake. Sometimes the FLs are bad, sometimes really bad. Sometimes they cause me to cycle in and out of sleep which is pretty brutal. Occasionally (last Saturday night, which is what prompted this thread) I will have significant flow limits without arousals -- I just trundle along with my squashed-down flow-rate curve, asleep through it all.
   
3. The flow limits do not cause much in the way of desaturations, so insurance company won't care about them. I'm getting my insurance coverage via my ability to create the severe positional apnea s**tshows upon command :-). I give myself one occasionally by accident when I doze off without the collar on -- prime opportunity is if I'm reading in bed since I'm reading in the chin-tuck position.
   
4. There is some relationship between leaks and flow limits which I don't understand. Leaks while I'm asleep always cause giant flow limits, and then occasionally I get giant flow limits without any leaks. And I have no idea what is going on!
   
5. I don't have much deep sleep, but I do seem to get plenty of REM sleep. Whenever I get some deep sleep going the flow limits will kick me out into light sleep. When I get kicked out of REM sleep I frequently get right back to REM sleep after the arousal, but the deep sleep is more fragile. (All that is according to my Fitbit -- I'm thinking that I believe it since I was wearing it during both the November and April sleep studies and it tracked to the hypnogram very well as to the three sleep stages it tracks. It only claims a sensitivity of 30 seconds -- so changes on the graph are recorded to the half-minute -- so it obviously misses the shorter arousals. But it does seem to see the bigger ones.)
   
6. I'm totally ok with the idea of buying my own vauto. I would kind of like to buy it in person, though, so that I can make sure that it's ok before forking over the money. But I live in the middle of nowhere -- a place called Outer Forgottonia, in fact -- so finding a machine within a couple of hours drive is a challenge.
   
7. I'm pretty skeptical about the entire concept of "titration" with respect to something when I don't understand what makes it happen. I got screwed by my November sleep study because it was one of those less-eventful nights, so that the conclusion was that I don't have sleep apnea. A "titration" based on a few hours? Maybe if those hours just happen to be representative, that works, but that is not necessarily produceable on demand! And the sleep studies are expensive! To give the orders of magnitude -- my 20% copay for my April sleep study was ~$600, with the insurance company forking over another ~$2500. I'm at my out-of-pocket max, so another sleep study this year would be over 3 grand for them -- which is more than the price of them just buying me an ASV, blowing right through the price of a vauto!
   
8. I do have my "am I just a sleep apnea wannabe" moments of doubt. One thing that is complicated for me is that I have a form of arthritis -- psoriatic -- where my joints stiffen up whenever I stay still for any length of time. (I call it Tin Man Arthritis -- I freeze up!) So an amazing great peaceful nights sleep will cause me to feel like Quasimodo in the morning, LOL. Fortunately the stiffness goes away quickly, and THEN I feel pretty good, but, no, I'm never going to be a happy camper waking up *sigh*
   

...It's all pretty confusing... What really annoys me is that I think this stuff is really interesting, but the sleep doctors that we've been afflicted with don't give a rip anything interesting!

[Sleeprider]

Well, Cathy, you have arrived. The medical mafia is not going to change. Whatever the insurance companies require to allegedly avoid the costs of funding CPAP and especially advanced PAP, lines their pockets by constantly denying the care the patient needs. Is it beginning to sound like an inside-job where the medical community wins from endless testing, and insurance wins because most patients drop out, self-disqualify by noncompliance or self-pay out of frustration?

[happydreams]

I don't blame you for wanting to lay eyes on a VAuto before spending money.  For more money, there's the option of Supplier #2, which I ended up using.  At the time of my purchase, there was no good local option, Covid was raging locally and there was no vaccine available to the public.  Supplier #2 sent me a machine and a full set of accessories and case for my VAuto.  I was pleased with the completeness of the set.

One thing about Supplier #2, is they stand behind their product.  My heater/humidifier had a problem 3 months after I bought it.  It overheated - basically the temperature control was pegged to maximum.  Water would run out in 2 or 3 hours.  It was uncomfortably hot and I had to turn off the humidifier entirely.  Supplier #2 replaced my unit with another VAuto.  Unlikely that would ever happen with a craigslist or local purchase...  If you decide to go with Supplier #2, you will get the best service and quickest answer to your questions by calling them.  There are some questions and answers that perhaps are best unwritten, but very easy to handle verbally.  I had a very good experience with them.

There may be other suppliers that are equally as good.  My experience is only with Supplier #2.

Totally agree with the medical/insurance mafia comment of Sleeprider.  It seems like a conspiracy to deprive apnea sufferers adequate treatment.  It's painful to read the stories on this board about how difficult it usually is to even be treated, never mind the correct treatment that matches the actual conditions.  

You have to ask yourself the question, do you want to see more possible improvement, or is how you feel right now perfectly fine?  If you want to improve, you need to change something.  I'd recommend a more advanced machine, like a VAuto.  This will give you more knobs to turn to improve your therapy.  

It's your move, make a change for the better.

[Geer1]

Yeah if you have to pay that much for a sleep study then no point, just get a vauto.

Does your correlation of leaks and flow limitation only happen with nasal mask?

[happydreams]

Cathy, I haven't checked recently, but my 2nd hand, sanitized and warranteed VAuto cost $800 in October 2020.  Compare that to your cost for a self funded sleep study with a very unlikely recommendation for a VAuto.  My recommendation is to go around the system this time and get a more capable machine for less money out of pocket.  Seriously, it only takes one phone call, and that VAuto is on the way.  If the machine isn't adequate for your treatment you can always sell it (or perhaps trade it in?) and get a more capable one.  You still would save both your money and your time.  That's a win/win.

On the other hand, if you find a local option for a VAuto that's a lot cheaper, that's not bad either.

If you haven't caught the subtext of this conversation, it is:  Be in control of your treatment.
Another way of putting it is, patient empowerment.  Sound a lot more positive than, "most sleep doctors will not effectively treat sleep disordered breathing", doesn't it?    If they did, there wouldn't be a need for AB.  The volume of posts on AB and other similar forums indicates they don't treat effectively, for whatever reason..  

Be proactive with your health.

[redvinesfamily]

I do have my "am I just a sleep apnea wannabe" moments of doubt. One thing that is complicated for me is that I have a form of arthritis -- psoriatic -- where my joints stiffen up whenever I stay still for any length of time. (I call it Tin Man Arthritis -- I freeze up!) So an amazing great peaceful nights sleep will cause me to feel like Quasimodo in the morning, LOL. Fortunately the stiffness goes away quickly, and THEN I feel pretty good, but, no, I'm never going to be a happy camper waking up *sigh*

Ok, this is just unfair. Sleeping well hurts?!? The first thing that popped into my head is that you need one of those 70s waterbeds so you're moving all night.   Hook er up to the garden hose and you're good to go. I bet you could find one of those out in the boondocks easier than you can find a vauto.