Newbie question (Why my new cpap machine increase the c.a.)

Hello to everyone. I found this forum is very useful for me (here in Europe we do not have something like this).
I'm a relatively new user (8 months) in the world of cpap(diagnosed with severe apnea, AHI-65). In this time I used a rental unit( System one PR560 Auto). After this months I decided to buy my own S9 Resmed autoset.
Both devices were zero hours when i start to use them. I don't understand why after I switched to s9 autoset i got a lot of central apneeas (but hypopneas is gone) to the same pressure/same mask. How can I improve/fix my graph. Thank you and sorry for my bad english.

This is my PR560 Auto graph ;




and this is my new S9 autoset graph;

first thing I see is that your pressure on the autoset is lower.

minimum pressure 6.4 on the autoset.

minimum 8.5 on the prs1.

No, the autoset min. pressure is 8,4 ,...not 6,4.

adin67 wrote:No, the autoset min. pressure is 8,4 ,...not 6,4.

and you've dialed in 2 on epr, which reduces the minimum pressure 2 cm. ergo, (and as you'll see on the sleepyhead report, 6.4.

palerider wrote:

adin67 wrote:No, the autoset min. pressure is 8,4 ,...not 6,4.

and you've dialed in 2 on epr, which reduces the minimum pressure 2 cm. ergo, (and as you'll see on the sleepyhead report, 6.4.

Yep it' s true, I understand now, but the other unit(PR1) was set in the same range and I hadn't many clear apneea...

Your total AHI is not much different between the machines. Less than 5 is considered to be a pretty good result.

Don't worry too much about central apnea vs. obstructive. Central apnea is not necessarily more harmful than obstructive apnea, just harder to get rid of.

Look at the more detailed data and see how long the individual apneas last. If they're short apneas, they aren't as meaningful.

The different machines don't necessarily give the same AHI with the same data. Even two trained human sleep techs looking at the same in lab sleep test results will get different numbers. The difference is more marked if you're having short or less severe apneas.

Distinguishing central from obstructive may tend to vary even more.

Auto works differently on different machines. EPR works differently from A-Flex. There may be other subtle differences between the pressure waveforms delivered by two different machines.

How do you feel? Some people would say you're "cured" in terms of the numbers.

archangle wrote: How do you feel? Some people would say you're "cured" in terms of the numbers.

Yes, I would say that I feel better(with s9), fresh in the morning. The only problem that concerns me if those centrl. apneas can be reduced (maybe if i increase the pressure) or ignore them...

adin67 wrote: The only problem that concerns me if those centrl. apneas can be reduced (maybe if i increase the pressure) or ignore them...

Increasing the pressure on a cpap/apap machine won't/can't fix centrals. Increasing pressure only works on the obstructive apneas and hyponeas because it's the airway tissue that is blocking the air flow so more pressure is used to hold the airway open.
With centrals the airway is already open and no amount of pressure with the cpap/apap machine can fix them and might make them worse.
Should centrals be numerous enough to cause a problem then a different type of machine from what you have would be needed.
Your number of centrals (even if they were all real centrals) isn't high enough to warrant that type of machine.

Best thing to do with them at this point....ignore them if you are sleeping well and feeling decent. It's normal to have a few centrals get flagged anyway.

Events interpreted as "central" apneas may be increased by CNS depressants like alcohol,
Benadryl, and many sleep meds. Cutting back (if applicable) could help.
[[[Some drugs need to be reduced under a doctor's supervision.]]]

adin67 wrote:

archangle wrote: How do you feel? Some people would say you're "cured" in terms of the numbers.

Yes, I would say that I feel better(with s9), fresh in the morning. The only problem that concerns me if those centrl. apneas can be reduced (maybe if i increase the pressure) or ignore them...

Don't obsess about centrals. They're no worse than obstructives. Just check and see that they don't last too long.

adin67 wrote:

palerider wrote:

adin67 wrote:No, the autoset min. pressure is 8,4 ,...not 6,4.

and you've dialed in 2 on epr, which reduces the minimum pressure 2 cm. ergo, (and as you'll see on the sleepyhead report, 6.4.

Yep it' s true, I understand now, but the other unit(PR1) was set in the same range and I hadn't many clear apneea...

your pressure on the pr1 was higher, you've changed the pressure settings between the machines, whether the small difference in your reports is because of the pressure, or because you're sleeping differently, or because the machines are scoring things differently is another question.

turn EPR off, or raise the minimum pressure on the autoset to get the same pressures you had.

Thanks for your answers, I will try to take account of them.