Hello Guest, Welcome to Apnea Board !
As a guest, you are limited to certain areas of the board and there are some features you can't use.
To post a message, you must create a free account using a valid email address.

or Create an Account


New Posts   Today's Posts

What is that spike in Flow limit?
#1
What is that spike in Flow limit?
Hi,

Today was the second time in 7 months where I've been able to sleep 5 hours with the CPAP on. However, I don't really feel refreshed and I feel sleepy. Additionally, according to my Apple Watch I "woke up" approximately 8 times, even though I clearly only remember waking up once before falling back asleep.

According to the CPAP data, however, I didn't seem to experience any OAs at all, so I'm a bit unsure as to what's happening. I noticed a surge in flow limit around the RERA flag, so maybe it has something to do with it? Would love to get your opinions on this, thanks!


Attached Files Thumbnail(s)
   
Post Reply Post Reply
#2
RE: What is that spike in Flow limit?
You could have chin-tucked, which would cause flow limitations due to the airway being occluded. I expect that would be the likely cause.Sometimes just shifting position can cause flow limitations simply by changing the angle of the head relative to the body. 

Remember not all flow limitations may or may not show up in the graph. Looking at the flow rate can provide more information as described in this wiki article.

https://www.apneaboard.com/wiki/index.ph...limitation
Post Reply Post Reply
#3
RE: What is that spike in Flow limit?
because you still have quite a few flow limits I would try moving the min to 8.  The large ones grouped together could have peen positional.
Apnea (80-100%) 10 seconds, Hypopnea (50-80%) 10 seconds, Flow Limits (0-50%) not timed  Cervical Collar - Dealing w DME - Chart Organizing
Post Reply Post Reply
#4
RE: What is that spike in Flow limit?
hi urachan

We can wake up and not remember.

Unfortunately, even if we include apneas, hypopneas, RERAs, etc. it's not a complete analysis of what COULD be disturbing your sleep. Some patients are very sensitive, and breathing events beneath even the 'smallest' of this list, that is a RERA, can still be causing issues. Now, I'm not saying that is the case here, but instead simply wish to bring this to your attention.

What I would also like to bring to your attention are the leaks. Typically we experience daytime sleepiness because of fragmented sleep, and so the objective becomes eliminated as many of the variables as possible that may be fragmenting our sleep. It's not unreasonable to assume that a leak profile like the one you shared might be fragmenting your sleep, so that is a potentially fruitful target to direct your efforts.
Post Reply Post Reply
#5
RE: What is that spike in Flow limit?
Thank you all for your responses.

@PeaceLoveAndPizza, Definitely possible as chin tucking has been a huge issue for me since I've started my CPAP journey. Interestingly, I've also found that chin tucking induces strong aerophagia as well, and although I got better at not doing it, I always seem to randomly end up chin tucking while I'm asleep. I also seem to be able to sleep longer when my wife slightly pushes my head up when she notices I'm chin tucking - so I've ordered a cervical collar to see if that eliminates the chin tucking issues.

@staceyburke, I actually bumped up the pressure to 8 yesterday, but sadly experienced aerophagia two hours into therapy last night - which is something I hadn't experienced in a while. But it's hard to tell if the pressure change caused it, or if I just had a bad case of chin tucking. I'll try sleeping a few more nights at this pressure and see what happens, the cervical collar should arrive in two days.

@cpapfriend, what are some steps I could take to reduce the leaks? I don't hear much air leaking when I go to sleep, so I'm not sure what could lead to these leaks. It feels tight enough to me, but should I strap it tighter?

I also happen to have one more question - is this breathing pattern (pictures attached) normal? It doesn't look smooth to me at all (referring to the pointy tops and short shallow breathing periods before the tops)


Attached Files Thumbnail(s)
       
Post Reply Post Reply
#6
RE: What is that spike in Flow limit?
There are many potential solutions you can try:

1) shave beard if you have one
2) try a different mask or different size of components of mask
3) make sure to wipe down mask between sleeps to get rid of skin oil
4) trial chinstrap or soft-cervical collar
5) adjust straps
6) trial mask liners
etc. in no order of importance.

Some of the peaks of the waveforms illustrate flow limitation, and there does seem to be some irregularity in others. It helps to know context, like if it's likely during a REM period.
Post Reply Post Reply
#7
RE: What is that spike in Flow limit?
Whatever else is going on, your leak rates are too low to worry about. If you look at the left panel you will see that your leak rate is reported at 0.15, not nearly high enough to cause you any problems. Sleeprider once told me that he doesn't worry about anything under 5.00, and he knows more about everything apnea-related than anyone.
Machine:  ResMed AirCurve 10 Vauto
Mask:  Bleep DreamPort Sleep Solution
Post Reply Post Reply
#8
RE: What is that spike in Flow limit?
Hi. I am back a few weeks later after tons of testing. Looks like I start to get really bad aerophagia at pressure 8, and it doesn't seem to have any noticeable difference on my sleep anyway, so 7 seems to be the sweet spot for me. I've also had my first 9-hour night with CPAP today so pretty happy about that! I don't feel that good today though, either because I still wake up throughout the night or because the damage SA has done on my brain hasn't been repaired yet.. I guess? I was free from aerophagia the first 4 hours of the night and then it caused me to wake up once every hour the other half, not ideal. I know it's a positional thing so I need to find the right positions for my body. I ordered a wedge pillow for GERD, so maybe that could help with aerophagia as well..

In today's sleep data I found this weird pattern (attached), would anyone know what this means? Basically my breathing is normally even (equal highs and lows) but sometimes highs gets higher and lows get lower, creating a wave pattern. Curious why that happens. Thanks.


Attached Files Thumbnail(s)
   
Post Reply Post Reply


Possibly Related Threads...
Thread Author Replies Views Last Post
  [Symptoms] ASV Flow Limits kshvine 2 157 05-17-2024, 08:27 AM
Last Post: unadvisedfun
  How to reduce flow limitations on Dreamstation Auto CPAP? CentralApneaUser909 4 1,024 05-13-2024, 08:52 PM
Last Post: Phaleronic
  Flow limitation on bipap(smoothing out) opo218 11 363 05-12-2024, 06:20 AM
Last Post: opo218
  Clear Airway and Flow limitations UARS SleepyGin 10 425 05-10-2024, 11:32 PM
Last Post: SleepyGin
  AHI 0.00 but flow limits increased jake79 15 507 05-08-2024, 08:40 AM
Last Post: BoxcarPete
Gross [CPAP] Double top flow rate ohno 5 264 05-07-2024, 11:44 AM
Last Post: Deborah K.
  unstable breathing with BiPAP (possible flow limitations?) shedu1337 3 250 05-03-2024, 01:21 AM
Last Post: shedu1337


New Posts   Today's Posts


About Apnea Board

Apnea Board is an educational web site designed to empower Sleep Apnea patients.