BiPAP - Good AHI but feeling tired

[jonron]

Hi folks,

I recently moved to a BiPAP machine as I was still feeling tired during the day while using the APAP machine. After using APAP for over a year with less-than-great results we did an in-lab sleep study. This showed my CO2 levels were slightly higher than normal, and apparently BiPAP can help with that, hence the switch.


Current settings on the BiPAP are
Min EPAP: 7
PS: 3.4

(Dr said we might slowly increase the PS to get more of a pressure differential. We initially tried a PS of around 6 but this triggered a lot of Centrals. Dr said the higher PS was probably causing me to hyperventilate)


I am feeling slightly better on BiPAP with the lower PS, but still pretty tired during the day. I recently learned (a little) about UARS and started looking into flow limitations. I have attached some OSCAR graphs over the last few nights. I'd appreciate any insight on to my flow limitation / other graphs look. Not 100% sure what I should be looking for here.

Also worth saying, the last couple hours of sleep I notice are normally disturbed, I normally half wake up and sometimes have feelings of anxiety.

https://imgur.com/a/S7kqU06

[Miss Emerita]

Hello, jonron! I'm very interested in following the thread you've just started because I'm having a similar experience. Could you reformat your charts a bit to make it easier for the experts to weigh in? The changes to make: hide the pie chart on the left so that more of the other information will be visible, and stack your graphs this way:

Events
Flow rate
Pressure
Leaks
Flow limitations.

I'm not seeing much evidence of FL on the zoomed-in views you've provided. Just out of curiosity, I'm wondering whether you could post one typical chart from your pre-bilevel days? Quite possibly the bilevel has already fixed a previous FL problem, and it'd be interesting to know whether that's true.

[jonron]

Sure, great idea - here are charts from a typical day on my previous APAP - interestingly the peak of the flow rate does look slightly flatter!

apap1.png (148.88 KiB) Viewed 2478 times

apap2.png (122.48 KiB) Viewed 2478 times

[jonron]

And this is last nights (on the BiPap) with the graphs formatted as requested;

b1.png (141.51 KiB) Viewed 2476 times

b2.png (123.48 KiB) Viewed 2476 times

[Miss Emerita]

Yes, that's my perception too, that the peaks are more rounded with the bi-pap. I hope an expert will be along soon to advise you about the CAs and your continued daytime tiredness. Many thanks for sharing the further information.

[Miss Emerita]

Bump for expert advice.

[Pugsy]

Bump for the usual.....

Detailed report in a format that we are used to seeing so we don't have to make WAGs.
viewtopic/t158560/How-to-post-images-for-review.html

And for the usual questions about ....
are you taking any medications for any reason....if so, what?
any other physical or mental health issues going on?
are you sleeping soundly or do you wake up a lot during the night?
how much actual sleep are you averaging?

[jonron]

No meds
Slightly overweight but not other real health problems
I normally wake up after about 6 hours of sleep then have what feels like broken up sleep for the last couple of hours. So around 6-8 hours per night is average.

[Pugsy]

I don't really see anything of great excite on the snippets of the reports you posted.
The increase in CA/centrals the last couple of hours of the night most likely are SWJ (sleep/wake/junk) false positive centrals from pauses in breathing while awake that last couple of hours tossing and turning and in and out of sleep kind of thing.
You might watch all the videos here and learn how to distinguish arousal/awake flagged events vs asleep events.
http://freecpapadvice.com/sleepyhead-free-software

It is possible you are still tired because you simply aren't getting enough quality solid sleep.
Why the wake up after 6 hours or so? Dunno but you probably have some sleep maintenance insomnia going on for some reason.
The list of culprits is quite long and sleep apnea is just one thing on that very long list.
It happens a lot....the apnea therapy goes great but people don't feel so great but it's because the fatigue isn't from something the machine can fix.
Sometimes medication side effects are to blame...hence the meds question.
Sometimes other health conditions play a part.

I don't see anything that just stands out screaming "fix me and you will feel better" except the fact that you report you often have trouble staying asleep for the last 2 hours of the night. I don't see anything on the reports that might explain why and the problem is there are so many potential culprits it's really hard for us here to just look at your reports and know why you aren't sleeping so great.

Keep working with your doctor to try to sort out the issue.
If you haven't had a good physical with routine labs lately ....get one and include some not so routine labs beyond the normal thyroid blood tests.
Like hormone levels especially if male (low testosterone causes fatigue) and also a vitamin D level test. Low vitamin D causes fatigue as well as messes with sleep quality.
Review your overall sleep hygiene to see if you are doing something that is bad sleep hygiene.
It wouldn't be impossible for your fatigue to be totally unrelated to your sleep apnea.

[jonron]

Thanks for looking it over!

Curious - would raising the Min EPAP make any impact? I seem to be sensitive to raising the PS too much at its current setting of 7 - seems to trigger more CA's.

[Pugsy]

Some people do find that using bilevel pressures seem to have a fine line where more PS (higher difference between inhale and exhale) can trigger centrals. Not common but not impossible either.
I have a friend who gets about 15 centrals per hour with PS of 4 and essentially none with PS of 3...so sometimes a small difference in numbers makes a huge impact.

Raising minimum EPAP will do absolutely nothing for central apneas. And I don't see a need for more EPAP for obstructive OAs or hyponeas.

If you are wanting to reduce centrals...try reducing the PS from 3.4 to maybe 2.4 or lower and see what happens.

[Patriot Partner]

Good topic

I also had elevated co2, and minimal centrals

Dog tired

[jonron]

If you are wanting to reduce centrals...try reducing the PS from 3.4 to maybe 2.4 or lower and see what happens.

Happy to try that, would doing so not negate the benefit of using a BIPAP machine though? I thought the purpose of BIPAP was all about having a pressure differential. As I understand it the pressure differential would help with my CO2 being on the high side.

I reduced my Min EPAP by 1cm and am seeing less centrals, still don't feel like I'm sleeping any better though

[Pugsy]

There is a small segment of bilevel users who find that the PS can actually trigger centrals instead of helping with the CO2 stuff.
Extremely small but it happens. That PS comfort comes at a price for some people.
Centrals occur when the carbon dioxide levels don't get high enough to trigger the brain to send the breathe signal.
For some reason having PS seems to wash out the carbon dioxide too much and the brain never knows it needs to breathe.
Why some people and not others? I dunno.
Sometimes the smallest amount of exhale relief will trigger centrals in this very small segment of cpap users.

I don't know that is what is going on with your centrals...it was just an idea to try to see if it did anything or not.
Heck...having no PS at all might not even make any difference.
I have no idea if the centrals are responsible for your not feeling as good as you would like. They could be arousal related and not real asleep centrals and thus more of a symptom of poor sleep than the cause of poor sleep. That's why I suggested watching all the videos so you would know if what you are worrying about is even an asleep flagged event. If you weren't asleep....they don't matter except for the fact they point to poor sleep quality in general.

There is a long list of stuff that messes with our sleep quality and how we feel and apnea is but one item on that very long list.

[zonker]

There is a long list of stuff that messes with our sleep quality and how we feel and apnea is but one item on that very long list.

i'm quoting this for emphasis and in hopes more people read this sentence.

THIS is maybe the most difficult thing for a new user(myself included!) to grasp. we live in a society that has been trained to go to the doctor, do what they say and voila! you are cured.

this was my thinking when i first got my cpap. and boy howdy was i proven wrong. there are many other things besides getting the good numbers that cpap brings. and now that i've gotten used to cpap, i'm exploring the other options.

/off my soapbox