Clear Area (Central) Question from Newbie

[gregoryjames]

Just completed night two and the majority of my events (5) are showing as CA and not as obstructive. So, here is my overall data



And then here are the 5 instances noted on sleepyhead (where I zoomed in to see the time before and after... the first two are almost back to back)

My main question.. does this fit the pattern of CA vs. Obstructive? (5 of my 8 events are noted as this - 1 hypopnea and 2 obstructive as well).

Also, there is no pressure increase ... if the machine senses it as CA does it not increase pressure at all?

Thanks SO MUCH for all your help - I am so new to this but wondering why these might be showing as CA...

On good note - I had like 100% pressure seal over the course of the night and I do feel really good this morning (up FAR earlier than I usually am in the morning!!)

[gregoryjames]

PS

I forgot to have on the mask pressure (I thought those stayed in same order day to day - ha).

I am just posting for one of the noted "CA's" as they all look the same - notice the "rumbling pattern" during the second half of the noted CA. Each of the 5 have that same pattern - almost flat for the first half and then the rumble - is that the maching sending the "burst of air?"

[GoodGuysFinish]

Many people have initial clear airway (CA) apneas during the first weeks of treatment. The number of CA you are getting is low. It is great that your obstructive apneas are so low that the CA is most of the score. Great Job!

The fluttery stuff at the end of the flat space inside your CA occurrence is the machine making light background pulsations to alert your body without awakening you. Pretty cool, eh?

Nice pictures.

GGF

[GoodGuysFinish]

by the way, the machine does not try to increase pressure when it detects a clear airway (CA) event, because pressure does not "fix" clear airway. The pressure is to hold open the airway, so would only increase if the airway seemed to not be open enough (obstructed).

Hope that explains it.

GGF

[gregoryjames]

Thank you- that makes perfect sense.

I agree - my sleep study showed 15AHI so the fact that I am down to only 1.1 AHI with what seems to be a really limited pressure needed is a good sign.

Truly appreciate all the encouragement and great posts I have been able to read on this forum so far!

Nice to wake up "early" this morning and just decide it was time to get up (as opposed to laying and going back to sleep as I have always done). Like my body was saying, "you dont need to stay in bed - you are ready for the day!"

[TASmart]

Those little pulses are the machine trying to determine if your airway is open or closed. It's how it determines if its a CA or OA.

[Pugsy]

The little "rumbling" right before the CA/central flag and/or sometimes you might see it before an OA flag is the ResMed FOT...Forced Oscillation Technique that it uses to help decided if the reduction in air movement it is sensing is because of a central or obstructive type of apnea event.
explained on page 8 of the manual I linked to below. Do you have a copy of the clinical/provider manual? If not here it is.
https://sleep.tnet.com/home/files/resme ... -guide.pdf

The FOT are little tiny sort of pulses...no where near the burst of air needed for central therapy.
Your machine can't do the burst of air because it can't increase fast enough or high enough. Central therapy would involve a machine going from maybe 10 cm to 22 cm in about 15 seconds or less. None of the regular autoset machines can increase that fast...and they can't go above 20 cm.

Your centrals do seem to be "real" mainly because the breathing around it looks like normal asleep breathing. Awake or semi awake breathing is much more irregular .
You might find this thread helpful since you already like zooming in on stuff and in this thread are links to other interesting threads.
viewtopic.php?f=1&t=114600&p=1110933#p1110933

It is normal to have a few centrals get flagged that are real centrals. Sleep stage transition or sleep onset centrals are normal to see. Not a problem unless we see a whole lot of them or the continually bounce a person out of sleep to an awake stage.
Of course sometimes we can have SWJ centrals were maybe an awake/semi awake pause in breathing gets flagged.

Obviously you didn't have nearly enough centrals to cause for worry. I would just shrug my shoulders and move on. Nothing you can do about them with your machine and there's no need to do anything about them with so few of them anyway.

Good job.

[GoodGuysFinish]

I agree with Pugsy, the waveform before (and after) the clear airway event seem to be normal NREM sleep pattern, so I also would have guessed you were sleeping through it. #5 event on Apr 18 was a little different, you may have been aroused by something, taken a couple slightly deeper breaths, and halted a bit before resuming nice sleep.

GGF

btw. ha ha I did use NREM in the sentence, begging the question about potential differences in breathing waveform in REM sleep.