Determining starting pressure for centrals.

[Jason1975]

I have an Autoset II currently on auto mode. My titrated pressure was 10 but through lots of rescan research, I found out that that is too low. I went to a second clinic and they also stated that it was too low of pressure. My question is: How do I know if the apnea events I'm seeing are central or obstructive? I realize the higher the pressure the more chance of centrals but if I'm still having a lot of hypopneas than its still a good chance that I need a higher pressure, correct? When I start getting too high, would my apneas increase and my hypopneas decrease or doesn't the hypopneas matter at this point?? Does anyone understand what I'm trying to say? My min. pressure on my machine is 10 and max is 20. I also found that I have a lot more hypopneas when I have EPR off. At EPR of 3, my hypopneas are usually lower. Make any sense? Any help would be greatly appreciated!!!!

Also, forgot to mention that in my two sleep studies, centrals were not an issue.

[jweeks]

Jason,

Eeeek. This one scares me.

There is only 2 ways that you could know if 10 is too low, just right, or too high. One would be in a titration study. The other would be to read the data card. If you had read the data card, you would know what kind of events you are having (it is in the data). If you had a titration, you would know what the right pressure is from the sleep study. And if you had a competent sleep doctor, you would be unlikely to have the range set wide open on your machine.

This is like giving someone a loaded weapon, and then being surprised that they shot somebody with it...only you are shooting at yourself here. You need a real sleep doctor, and you need a real sleep study at a real sleep clinic. Anything less would be rolling the dice. Find a board certified sleep doctor with some real world experience, and schedule a sleep study at a major cardiac center or some other modern sleep lab.

-john-

[jdm2857]

As John said, you really need to be able to read your data. The S8 AutoSet II, however, does not distinguish between obstructive and central apneas. (The S9 AutoSet does.) You will, however, be able to see your apneas and hypopneas and how they relate to the automatic pressure changes your machine makes. The S8 AutoSet II, like many of its predecessors, is a bit conservative at raising the pressure when the current pressure is at or above 10 in order to avoid inducing centrals.

[LoQ]

For what it's worth, I just had an in-home study ordered by a sleep specialist (neurologist), done with an S7 Autoset. In my lab study, I had only central events during the titration, so it's not like that wasn't a possibility. The home study showed that my CPAP setting was too low. I've raised the pressure per doctor's orders and am feeling a little better now.

[jdm2857]

The disadvantage of home titration is that fewer channels of data are recorded. No EEG, breathing effort, or EKG data, for example. But the advantage is that you are sleeping in a familiar setting, which is more representative of a typical night's sleep. That can be a biggie. And it costs much less.

[Jason1975]

Thanks for all the replies. I have had two titration studies and they both reported my pressure at 10. However, I went to a different sleep doc. and they reviewed my sleep study data and they said that the time I was given in REM was not very long and should have been recorded longer. She thought that 10 was ok out of REM but once in REM, my apneas appear clustered. That's why I am asking this question. I have been doing my Min. pressures between 10 and 13. Not really much of a difference in my AHI's. Still between 8 and 14 every night.