Can a CPAP machine treat central apneas?

I, too, have mostly central apneas and hypopneas. I don't think my CPAP makes a difference in either, but I have been monitoring my central/hypopneas with a pulse oximeter. I just stop breathing, and 30 seconds go by as my O2 sinks, then I breathe again. My CPAP shows the ratio shown in the image above. But when I talked to my pulmonologist, he showed me his report. As far as he could see, my sleep apnea was 'fixed' because my AHI was 4 and under. All that report showed was the AHI. He was apparently not able to drill down. And of course, the O2 level isn't shown either. Nor is the time they appear, which I think would be helpful for treatment. Just bothers me that this information is available to the machine and the user isn't available to the doctor.

I recommend you go to apneaboard.com and see the marquee at top, a thick black one. On it, mostly toward the right, is OSCAR. That is a freeware, safe, that you can download and make an account. Then, remove your SIM card from the slot on your machine and read it, either in a reader or in a slot in an older PC/laptop. Allow OSCAR to read the data, and soon you'll get a comprehensive depiction of all your important and relevant data. This data should match all data available to a sleep coach or to a physician specializing in sleep and sleep disturbances.

I have mostly Central Sleep Apnea. 30 to 50 events per hour. I also have an O2 ring and suggest everyone get one. First time I used my O2, it showd my Oxygen dropping by 8-10 points every 40-45 seconds all night long. This cycle seems to happen even though I'm breathing as I can watch it go down as I am breathing at 15 Breaths per minute (which is every 4 sec). This would happen as i was very relaxed and almost asleep. It would cycle between 98% to 88% all night long at an almost fixed rate or every 40 seconds. I put the ring on my wife and kids and it was steady. What is going on with me. I don't wake up and gasp. I don't think I'm obstructed. I don't snore. I even had a dental appliance made to advance the jaw, which would stop obstuction from the tongue going back while sleeping. At times the O2 would go to low 80% and even below for 10-15 minutes at a time. Still after 5 complete sleep studies have I NOT received an description of what is happening. The docs just seem to want to "try this and if it doesn't work we will try something else". Central Sleep Apnea is hard to treat. From information I gathered from the net, supplamental Oxygen via a nasal cannula "makes it melt away" in some patients. I could not get any of my doctors to even try it.

I believe its an lung oxygen transfer problem that happens with very shallow breathing due to possibly some lung defects in the part of the lung involved during shallow breathing. The CO2 does not build up ( which is the usual feedback to cause a breath) because CO2 transfers much easier then O2. So with no CO2 feedback to cause a breath the O2 drops till a back up system detects the low O2. This will either open more blood flow to the lungs or deeper air flow etc, which restores the O2 but now it goes to high and the system cycles. this is what engineers would call a feed back loop over compensation. So much for my theory.

Yes, you need to download your cpap data to OSCAR and look at your flow to see if it stops or just get reduced etc. You need to expand the view so you can see the individual events. Lots of interesting data in there.

My first Tx was a BIPAP machine which did nothing but made it worse as I was now getting Chayes Stokes breathing pattern from it. After 5 complete sleep studies in a lab, my last sleep study, which was to titrate me for an ASV machine (needed to get insurance to pay) seemed to indicate the ASV machine will reduce the events. My first night with the ASV machine, the events were under 5, and almost always an hypopnea rather then apnea. This would appear to be great news. However, the machine is designed to keep the Minute Ventilation to a fixed level and will vary the mask pressure up and down as it learns what events lead to the apnea and it tries to intercept this before it happens. This results in very high pressures at times,(machine max at 24), which is difficult to prevent mask leaks.
I coordinated my O2 ring data with the ASV machine data into OSCAR. Need to put in time correction to get them both aligned for some strange reason. There is no way go correct the time stamp of machine even when traveling internationally. The O2 ring gets it time from the apple watch. They were off by just under 2 minutes and hours because of DST. Interestingly, the O2 will still go down at times to although not as low as without the ASV machine. The machine is happy keeping minute ventilation at a fixed level even though the O2 is now in mid 90s% rather than 98% or so.
I don't know why they don't make a machine whose goal is to keep the O2 up rather then just a nice flow rate. I assume there is a lung problem that the doctors tends to ignore with central sleep apnea. Their goal is to get events down. Its a very complicated system with various feedback loops, that's pretty simple to understand with Obstructive Sleep Apnea. I'm not so sure they (the doctors) really understand the problem or cause with central sleep apnea. I have my own theory but still need to get doctors to do more testing. Make sure you get a Pulmonary Function Test, which will tell you how good your lungs are doing. (obviously, a big part of the equation).

Anyway, to answer the original question: YES a machine can help with central apnea but you probably need an ASV machine not a normal CPAP or BIPAP. They are expensive and you may need a sleep study to prove it works for you to get insurance to pay. I have traditional medicare with an insurance secondary, and so far everything has been covered.
My machine as an aircurve11 ASV auto.
Hope this information helps.
I'll check in randomly to see if anyone has further questions.

Just a comment to synchronize the O2 ring with the Cpap data in OSCAR
What I do, either at the begining or end of a session, is breath in and out very deeply 3 times at an exact known time from the ring. Do it a little after you started the CPAP machine.
Note the time, and try to start on an exact minute beginning. Do this again exactly one minute later and then again one minute later.
In Oscar you can easily spot the three deep flow breaths. You have to expand the view to see it.
Do this by clicking on a narrow part of the flow pattern where you think it is.
Then in OSCAR click upper left FILE then Preferences then CPAP.
There will appear in upper a CPAP clock drift.
Put in numbers to make the time of your first breath match the time stamp in OSCAR when you VIEW Daily your flow rate.
In my case I had to enter 58 min 6 seconds while in Day Light Savings Time.
Hope this helps.
Having the Oxygen data along with the breathing data is most helpful.
Also the O2 ring records motion. This is also very useful data.
I notice my O2 is very steady when my motion is zero. And the flow data is also very steady.
And the ASV is not jumping all over the place trying to control things.
Maybe another piece of the puzzel!

An ASV is really the only effective treatment machine for central apnea, and may be needed for 'complex' apnea where the two forms are present in one body. For some reason I still get statements from qualified physicians, even experts such as electrophysiologists, who tell me that I might need a BiPAP machine if I have the odd central. I don't bother pointing out that the heavy majority of CA sufferers continue to do poorly on anything but the admittedly very costly ASV machines.
I sincerely appreciate seeing your detailed and comprehensive responses here.

gloaming
Yes, they said I am mixed although not sure how or where the obstructive part is happening, unless it is something very internal with the lungs. My airway is clear.
99% are obstructive and that seems to be all they really know.
Yes, the ASV machine does work but if you look at the OSCAR data, it shows the machine going absolutely crazy trying to adjust the pressure all the time, even with each breath. In my case it goes up to the maximum the machine can put out (24), which is very hard to prevent leaking. When it does, the noise bothers my wife. I tend to hear it but work in into my dream. It also seems to happen, not in sync with my breathing. I seem to breathing out when it is trying to push air in at 24. When I hear the leak, I try to stop the noise by breathing in, but it does not seem to work.
I have lots of different masks that I try.
Airfit20, Airtouch20, Airfit30, Airfit30i, Airfit40.
So far, I think I like the Airfit30i best.
What I'm getting now is a stiff neck, and I think its from the straps of the mask.
What I am concerned about is when I am not sleeping. During the day, my O2 ring shows the O2 dropping all the time.
While watching tv and relaxing, almost asleep, it can drop for 10 minutes at a time to low 80's or less. So I'd like to know WHAT is exactly going on and IS there a way to correct it. I'm watching the REMEDE gadget, but it seems to be programmed to only work during your sleep time. I need to get more information although I don't think I'm ready for it yet.

The ASV machine is amazing in stopping "events".
Previously I had almost all Central Apneas 20-30 an hour.
With the ASV, the one that do occur are almost all Hypopnea and around 5.
Again, thanks for your response.

The RESMED machines show 'clear airway' as an indication of CAs. The Airsense and Curve machines can send a pulse of air down the tube, and if it bounces back, that means an obstruction. That same pulse that doesn't bounce back, or does weakly, indicates no obstruction and that you have simply stopped breathing. That, is open airway, but not breathing into it. The machine is supposed to repeat this pulse in an attempt to make your subconscious mind start breathing again. Like a nudge, or an elbow. I know, it's weird, but this is the engineering built into them.
I have hypopneas each night, but they are relatively innocuous if they don't come one after the other and pile up on the heart and the sympathetic nervous system to make them gang up on your sleep. This is the problem with obstructive events and the arousals they cause...the wreak havoc with one's normal stage successions of sleep, even preventing deep sleep and REM sleep.
So, if your machine says you have the odd obstructive event (this will be depicted clearly with blue vertical lines in the time chart in OSCAR) [You can hover your cursor over each event and see how long it lasted, too, a very handy, and sometimes alarming, feature.] it might just mean that you're on your back and chin-tucking, or tongue-swallowing. Try to stay on your side, or use a soft foam cervical collar to keep your chin from dropping too close to your chest when you are asleep on your back. Just a suggestion.