Pressure Questions

I am a relatively new user, not quite 3 months into using an apap. I did not have a split night sleep study and had no titration. My sleep study report (just obtained from the sleep docs office) says I have mild obstructive sleep apnea with an AHI of 6.5, respiratory disturbances of 11 and oxygen desaturation as low as 87%. Respiratory events were almost exclusive to the supine position. My arousal index was elevated at 46.1 with most arousals spontaneous in nature. I did not meet the criteria for a split study. I was awakened during the night and asked to try to sleep on my back. I couldn't get back to sleep and it was too late for a sleeping pill. Instead, I took a xanax, which was noted on the report. Only then did I sleep on my back.

The doc started me on a autopap with 4-20 pressure (I have a Resmed S9 Autoset). Over the past two months my 95th percentile pressure averaged at 10.3. My average AHI is 2.0. ( I had only two nights with numbers that were high, up to 4.7--it was boiling hot, my mask would not behave, and I am recovering from a shoulder injury forcing me to sleep on my back.)

On meeting with the PA at the doctor's office she suggested two alternatives for pressure. First, she suggested getting a different machine and going straight CPAP with a pressure of 10. I said I liked my machine. I should have said that my machine will do straight CPAP. Frankly, I was surprised that she didn't know that. But after I said I liked my machine she suggested leaving it on auto with a range of 6 to 20 and if I wasn't satisfied with that, moving it from 7 to 20. She said to bring it in to the DME to modify the pressure. I said I could do it myself. She was reluctantly fine with that and said try the six and then maybe up to 7. I did 6 last night and it was a good night--AHI 1.7. But most nights are good nights. Why not seven? Or eight? Or even 10?

I had a bunch of other questions so I did not discuss the pressure issue any further. But on reflection, I am not sure how to evaluate the options and if the 6 or 7 minimum setting makes sense. Anyone have any thoughts on the issue? Anyone know if it is "better" or "worse" to have a variable or constant pressure?

With a 95th percentile of 10.3, I think the consensus of this board would be to set your AUTO at 7-8 on the low side and 12-13 on the high side.
IF you were to go to straight CPAP a setting of 10-11 would be appropriate. It would be 'how you feel' that would determine whether AUTO of fixed is best for you.

If I could obtain your AHI numbers I wouldn't have a complaint in the world. I am new to this also and am struggling with AHI's in the 7's to 12's on my best nights. I have tried everything and am close to giving up. Good luck with your Journey !!!!

goldfinch wrote:Anyone know if it is "better" or "worse" to have a variable or constant pressure?

I know it's better for me to have variable pressure, but I don't know what's best for you. Do the pressure changes bother you? How do you feel in the morning and during the day?

Assuming you're not using EPR, I'd use the "two under, three over" rule of thumb and try a range of 8.3-13.3 cm H20. This might bring your AHI down a bit, because starting at 4, you probably have a few events before the machine finds your pressure, and probably have a few more because it drops too low during the night. It may also reduce the trips to the higher end or the range. If you start throwing OAs because the pressure is too low, the machine will sometimes chase a chain of events to much higher pressures than it would have set if the pressure had been high enough to begin with. With EPR, you may have to raise the pressure up to however many cm EPR you set.

Most of the drawbacks of APAP come from setting too wide a range. I'm not sure why your doctor went from trading the machine in on a CPAP at 10 cm to running APAP at 6-20 cm, or why she's hesitant to let you set the minimum higher when she was about to lock you in at 10 cm. If she was afraid to have you adjust the machine yourself, it's possible she's just not very familiar with it, or with APAP in general.

You want the minimum number to be high enough so you feel like you can breathe and don't have any events while you're trying to fall asleep. If you consistently have OAs or Hyponpneas when your pressure drops below a certain level, raise the minimum above that level. If your machine spends a lot of time resting on the bottom of the range you set, lower the minimum a little and see what happens.

Unless the high pressure is causing other problems, the maximum number should be high enough that you rarely hit it. You could leave it open, but it will be a lot easier to keep the mask on your face if you don't have to cope with 20 cm.

It seems to me that at this point, you've already got a better idea than anyone else what is going to work for you. I think you can take it from here. Of course you'll ask your doc and the forum folk when you have questions, but you are already the world's leading expert on your own breathing.

If 10 doesn't bother you, I'd probably put it on 10-20 and watch it closely for a while. Unless you start getting a lot of central apneas, be happy.

As for setting the higher level, my thinking is if the machine doesn't ever "get crazy" and go to a too high pressure, just leave it as is. Mine is set to 10 to 20 and it only occasionally bumps up at all and only occasionally goes above 12 for a minute or so.

If it ever goes above 12, that's sort of another flag to tell me something is going on and I should investigate.

If you have problems with the pressure running away, try to figure out why, and then, if necessary, just set the upper pressure to a more reasonable limit.

Well, tonight I'll bump it to 7. Six did seem rather pointless. I'll try it there for awhile and then probably move it to 8. I am not feeling a lot of confidence in my PA because the advice seemed off. Or, maybe I'll jump to 8 right away because I am stuck sleeping on my back until my rotator cuff injury is a bit better.

I feel fine so in a way this is a bit academic. But stopping even more apneas can't be a bad thing.

I don't notice pressure changes unless I am having a leak problem. I do have EPR set at three. Once in a while I wrestle with bad leaks. But not often. My general leak data almost always looks fine except for two bad nights when I was forced to sleep on my back and it was hot, hot, hot. After a plea for help here I ended up cutting up an old piece of underwear to make a mask liner. So, I don't think that I will worry about the high end unless I have more problems.

I can't say I feel better on the PAP. I never felt that bad. I got tested for sleep apnea because I would awaken unable to breathe, struggling to get air into my lungs. This would happen once or twice a month and it took me a number of years before I did anything about it. But I never felt overly tired. The treatment is working for me because I now never wake up unable to breathe. My person at the DME asked me how I felt and I said I feel exactly the same but I am no longer afraid to go asleep, fearing that I will wake up unable to breathe.

goldfinch wrote:I am not feeling a lot of confidence in my PA because the advice seemed off.

goldfinch wrote: First, she suggested getting a different machine and going straight CPAP with a pressure of 10.

It could be they are tied to the DME somehow....keep an eye out for that. Or it could be she is the kind who simply doesn't like autos for whatever reason.

My DME is fab. (I posted about it in another thread-- viewtopic/t66603/viewtopic.php?f=1&t=66 ... 37#p620537 ). There is no relationship between the sleep doc's office and the DME.

I guess I just will have to be puzzled about where the PA is coming from.

I set it at 7 last night with no issues. AHI 1.2. I haven't looked at the details yet. I think I'll hold it here for a few days to see what readings I get and then move to 8. The nice thing was that I was able to sleep on my side for part of the night, so that may also positively effect my AHI.

Guest wrote:If I could obtain your AHI numbers I wouldn't have a complaint in the world. I am new to this also and am struggling with AHI's in the 7's to 12's on my best nights. I have tried everything and am close to giving up. Good luck with your Journey !!!!

Ala1051,

Please post what specific problems that you are having and let us help you. Start a new thread with your problem in the title. There are lots of experience people here and we can tackle each issue.

Ala1051,

Please post what specific problems that you are having and let us help you. Start a new thread with your problem in the title. There are lots of experience people here and we can tackle each issue.[/quote]



Thanks "outasync" for asking. I guess I am just frustrated because I can't seem to get around a certain AHI and maintain it there. I can have a night in the 5's and wham !!!! next night nothing different happens but here comes an AHI of 10 +. I have made a very valiant effor even investing in a Full Face Comfort Gel mask on my own without my Insurance Company. It seemed to make a good seal and a good night's sleep but still the up & down AHI's. If I could get in any one area even if it were high I would be content but when a low is thrown in to tease me it fristrates me instead.

Thanks again.........

If possible can you please posts your graphs, we can then see the relationship between pressure, events, and all the other variables.

LSAT wrote:With a 95th percentile of 10.3, I think the consensus of this board would be to set your AUTO at 7-8 on the low side and 12-13 on the high side.
IF you were to go to straight CPAP a setting of 10-11 would be appropriate. It would be 'how you feel' that would determine whether AUTO of fixed is best for you.

LSAT

Very good call - for many reasons

DSM

Guest wrote:If I could obtain your AHI numbers I wouldn't have a complaint in the world. I am new to this also and am struggling with AHI's in the 7's to 12's on my best nights. I have tried everything and am close to giving up. Good luck with your Journey !!!!

But,

With desats at the 87% level the small AHI is comparatively meaningless. It is goldfinch's blood oxygen levels that justify cpap and getting the machine right.

Cheers

DSM

goldfinch wrote:Well, tonight I'll bump it to 7. Six did seem rather pointless. I'll try it there for awhile and then probably move it to 8. I am not feeling a lot of confidence in my PA because the advice seemed off. Or, maybe I'll jump to 8 right away because I am stuck sleeping on my back until my rotator cuff injury is a bit better.

I feel fine so in a way this is a bit academic. But stopping even more apneas can't be a bad thing.

I don't notice pressure changes unless I am having a leak problem. I do have EPR set at three. Once in a while I wrestle with bad leaks. But not often. My general leak data almost always looks fine except for two bad nights when I was forced to sleep on my back and it was hot, hot, hot. After a plea for help here I ended up cutting up an old piece of underwear to make a mask liner. So, I don't think that I will worry about the high end unless I have more problems.

I can't say I feel better on the PAP. I never felt that bad. I got tested for sleep apnea because I would awaken unable to breathe, struggling to get air into my lungs. This would happen once or twice a month and it took me a number of years before I did anything about it. But I never felt overly tired. The treatment is working for me because I now never wake up unable to breathe. My person at the DME asked me how I felt and I said I feel exactly the same but I am no longer afraid to go asleep, fearing that I will wake up unable to breathe.

goldfinch

Do you use an anti-leak strap with that mask ? - if not look at pad-a-cheks website for what she has there. I am about to buy a new one - saved my soul that little starp did

DSM

PS at some time I'll try the new Qattro FX mask as it may be even better at eliminating leaks.

D