Are these CA events real, or misdiagnosed OAs?

[JonathanBravo]

Hi all,

I've been on APAP treatment for over a year now. I've posted here a few times. As the title says: my question is, are the CAs correctly assigned, because that changes how I change my treatment from now on.

My original diagnosed AHI was about 17, and now with treatment I range from 3-7 AHI. I typically get 0-2 OAs per night, but many, many CAs.  Using an Airmed 10, with F40 mask, and settings of 8-10 with EPR level 3. I'm a side/front sleeper and if I turn down the minimum air it ends up ramping it up to 8 anyway because that seems to be what I need, and if I turn down/off EPR I wake up 1000x a night with leaks. 

I've attached example pictures from last night below.

Thank you.

Edit - I think 'misidentified' is better than 'misdiagnosed'.

[super7pilot]

You had zero leaks and your pressure went up to 9.9cm. So it makes no sense that lowering the EPR (that is likely causing your CA’s) would create leaks.

[jdougc]

Sorry to see so many real clear airway apneas.
You may need a bilevel to treat both of your CAs and flow limitations.
You could try an experiment and lower EPR to 1 and your maximum to only 8.6, your median for a few nights to see if the CAs drop.

[JonathanBravo]

You had zero leaks and your pressure went up to 9.9cm. So it makes no sense that lowering the EPR (that is likely causing your CA’s) would create leaks.

Logically, absolutely, it shouldn't cause leaks. But in practice, across a sample size of several days, it does cause leaks.

[Dormeo]

The CAs look like they are coming after arousal breathing, and after the first few, you have a period of unstable breathing.  

Arousal breathing tends to be deeper than asleep breathing, and the flow-rate trace will look messy.  See attached samples.

There are two theories about why CAs sometimes follow arousal breathing.  One is that the deeper breathing washes out some CO2 from the blood stream, slightly delaying the "breathe-now" signal to the brain.  Another is that sensors in the chest wall signal to the brain that there's too much deep breathing going on.

It's pretty common to see a period of unstable breathing once CAs start, because recovery breathing after a CA tends to be deeper than asleep breathing and sets off a new CA.

Do you know whether CAs were identified during your sleep study?

I don't know why you have leak problems after you turn EPR down or off.  In your place, I'd try again, maybe just turning it down to 2.

If you're reluctant to do that, you might try using a constant pressure, with max = min = 7.  If that results in more OAs, then you'd need to increase the pressure.

The next time you post a chart, it'd be helpful if you would provide all and only these graphs:  events, flow rate, pressure, leaks, flow limitations, snores.

[SarcasticDave94]

If lowering EPR causes leaks you'll have to point it back to the source. Mask, adjustment, fit. If for example EPR 3 is on or off that 3 difference should not affect leaks if things are doing well with the mask.

Since this is a new thread, you'll have to answer the question, what did the sleep study tell in detail? Specifically the CA.

[JonathanBravo]

The CAs look like they are coming after arousal breathing, and after the first few, you have a period of unstable breathing.  

Arousal breathing tends to be deeper than asleep breathing, and the flow-rate trace will look messy.  See attached samples.

There are two theories about why CAs sometimes follow arousal breathing.  One is that the deeper breathing washes out some CO2 from the blood stream, slightly delaying the "breathe-now" signal to the brain.  Another is that sensors in the chest wall signal to the brain that there's too much deep breathing going on.

It's pretty common to see a period of unstable breathing once CAs start, because recovery breathing after a CA tends to be deeper than asleep breathing and sets off a new CA.

Do you know whether CAs were identified during your sleep study?

I don't know why you have leak problems after you turn EPR down or off.  In your place, I'd try again, maybe just turning it down to 2.

If you're reluctant to do that, you might try using a constant pressure, with max = min = 7.  If that results in more OAs, then you'd need to increase the pressure.

The next time you post a chart, it'd be helpful if you would provide all and only these graphs:  events, flow rate, pressure, leaks, flow limitations, snores.

Thank you for your reply. 7 Central events were detected in the sleep study - significantly fewer than the OA events. I've attached the report to this message. I'll try again with the lower EPR, and maybe try the constant pressure too.

[jdougc]

Your sleep study showed you slept almost 1/2 the time in the supine position, on your back. Have your switched to mostly on your side now?
If you are on your back an inclined pillow or adjustable would elevated your head and help minimize apneas.
Good luck.

[Deborah K.]

Your leaks are quite low and nothing to worry about.

WOW! I just saw your sleep study and you had low CAs. I'm amazed. I hope someone can help you determine what is going on. I'll PM Sleeprider.

[Dormeo]

Thanks for the sleep study. The CA index was pretty close to negligible, so I think it's fair to regard the CAs as treatment-emergent. I'm a little surprised, however, that they haven't settled down over the year you've been using your PAP machine. Still, let's see what happens if you revise your settings.