Complex Sleep Apnea

Pugsy or someone else -

I've seen it mentioned that complex sleep apnea is seen in upwards of 15% of patients that are on CPAP therapy. I've read a few theories on the forum and on a few sites. The question I have is if someone is diagnosed with CSA, are there instances where it resolves itself as your body adjusts to the improvement in gas exchanges.

My machine has now been set to a static pressure of 10.5 the past 3 days and I've had AHI's of 2.5, 3.6, and 6.7 with almost of all of my events being CA's. I'm hoping it's because of fragmented sleep, which I'm still struggling with. Going to call my doctor tomorrow for a follow-up, but was just curious.

CompSA where the centrals are only present as a result of xpap pressures is different from central sleep apnea where the centrals are caused by something else (and most often we don't know what that something else is).
If centrals are present in large numbers during a diagnostic sleep study (thus the central sleep apnea diagnosis) we can't expect them to go away as a person adjusts to cpap therapy because cpap therapy isn't the cause of those centrals in the first place.

Right, so if the CA's are present as a result of pressure, are there instances where they disappear when your body gets used to the pressure? Or, do you have to use another device (ASV?)

jnew71 wrote: so if the CA's are present as a result of pressure, are there instances where they disappear when your body gets used to the pressure? Or, do you have to use another device (ASV?)

Yes....I have read that CAs that are related to pressure will eventually go away on their own as the body readjusts its breathing rhythm. Not always...but far from impossible. Takes months though...from what I have read...like 6 months to a year.

ASV use...that depends on just how many centrals (that are caused by the pressure itself) and what effect they may have on the person as to whether stepping in with ASV machine happens to be needed.
If your AHI is 4.5...and each and every one of your events were centrals and they all were solely related to the pressure itself..still wouldn't warrant ASV use unless someone was having some significant problems.

Remember some centrals are considered just normal and not all are caused by cpap pressure. Sleep onset centrals are considered normal and not usually a problem unless they are so numerous we repeatedly keep getting bounced out of sleep and simply can't get past them so that we can proceed with our normal sleep cycles
Remember that some "centrals" as flagged by out machines may not be "real" centrals but instead may be SWJ or awake breathing irregularities getting flagged...so those wouldn't even be considered when evaluating ASV machine needs.

When someone admits to having fragmented sleep...then we know that there is a greater chance of having more SWJ centrals or simply more sleep onset centrals. So it makes it difficult to figure out if the centrals we are seeing are related to the pressure itself or simply a central that wouldn't be a big deal anyway.

If the AHI is 5.0 and under...and even if they were all real deal not SWJ centrals....and even if you slept solidly and didn't have fragmented sleep issues....it would be unlikely that ASV therapy would be needed or wanted.

When someone tells me that they have a lot of fragmented sleep then I can't help but wonder if any centrals flagged are the real deal or SWJ awake/semi awake breathing irregularities getting flagged.

jnew71 wrote:I've had AHI's of 2.5, 3.6, and 6.7 with almost of all of my events being CA's.

Of these AHIs ..the only one that would maybe raise an eyebrow in terms of excessive centrals would be the 6.7 AHI and then the eyebrow would only stay raised if this happened often. Random fluke "off" nights, even if we sleep soundly, aren't a cause for alarm.

Are you trying to figure out if you need ASV therapy? If so, I doubt it based on what you have said so far.
You would need to see a lot more "bad" AHI nights than what you are showing here and you would have to say you slept soundly (thus eliminating the possibility of SWJ centrals clouding things).
Unless centrals are present in much larger numbers than you are seeing it is unlikely that a doctor would do anything about 5 or 6 centrals per hour beyond saying "give it time". Even if they are related solely to pressure there is a good chance they will reduce or go away on their own with time.
Now if you were seeing 10 to 20 per hour..each and every hour for each and every night...then that might be a different story but a random 6 to 7 AHI that is mainly central in origin isn't going to need ASV when the other nights the AHI is well under 5.0.

One last question and I appreciate all the feedback. Even with the junk CA's due to breathing irregularities when in and out of sleep. Is there any associated drop in O2 sat to worry about?

jnew71 wrote: Even with the junk CA's due to breathing irregularities when in and out of sleep. Is there any associated drop in O2 sat to worry about?

SWJ centrals don't normally cause any drops in O2 levels.
Sleep onset centrals might cause a drop if the centrals are numerous and back to back for several minutes. That's one of the situations where ASV might be indicated but it takes a lot of them or some massive long duration centrals to cause a drop in O2 levels.

Get SleepyHead if you haven't already done so.

Look at the flow rate waveforms and see how long your centrals last and how complete they are. If they're only 11 seconds long, it's a lot less worrysome than if they're 30 seconds long.

Thanks Pugsy - I guess we'll see what he doctor says tomorrow. 3 straight nights with AHI over 6 and virtually all are CA's.

jnew71 wrote:I guess we'll see what he doctor says tomorrow. 3 straight nights with AHI over 6 and virtually all are CA's.

That would warrant a discussion with the doctor for sure especially if you tell us you slept soundly for the bulk of the night.
Then we can't blame SWJ if you slept soundly.