AHI all over the place lately

[Jason1975]

I've been struggling with trying to keep my AHI under 10 ever since I was put on cpap almost 2 years ago. I have an AutoSet II on auto mode. My pressure settings I had set from 10-20. It seems like I go in spurts. I can have ahi's of 8-10 for a few months straight and then all of a sudden they jump from 14-20. Could allergies cause this or what? I've been trying different ranges and it seems like my machine works better if I have my min. pressure close to my original prescribed pressure. But then again, other nights I think the opposite. When I have my minumum pressure set at 8, my 95th % is like 10 something with high ahi's. When I have my minumum pressure set at 10, my 95th % usually is in the 11 range. When I have my minumum set at 12, sometimes my 95th % stays at 12 and sometimes it goes up to like 13 or 14. Last night, my ahi was 21 with an ai of 4.1. My minumum pressure range was set to 11 and my 95% said 11.6. Any thoughts?? I just can't get any consistancy with anything. I just so discouraged.

[Mary Z]

Jason1975, I have the same problem and I know how frustrating it can be when you're doing everthing you can. I have been told with the ResMed machine to pay more attention to the AI than the AHI because of the way the ResMed scores hypopneas. Still I know your AI is not in the range you want it to be. I am on Spontaneous Mode with pressures of 24/20 and I have days when I meet the target, but not consistently.
Sorry, no answers, just wanted you to know you're not the only one out there.

[ozij]

I've been struggling with trying to keep my AHI under 10 ever since I was put on cpap almost 2 years ago. I have an AutoSet II on auto mode. My pressure settings I had set from 10-20. It seems like I go in spurts. I can have ahi's of 8-10 for a few months straight and then all of a sudden they jump from 14-20. Could allergies cause this or what? I've been trying different ranges and it seems like my machine works better if I have my min. pressure close to my original prescribed pressure. But then again, other nights I think the opposite. When I have my minumum pressure set at 8, my 95th % is like 10 something with high ahi's. When I have my minumum pressure set at 10, my 95th % usually is in the 11 range. When I have my minumum set at 12, sometimes my 95th % stays at 12 and sometimes it goes up to like 13 or 14. Last night, my ahi was 21 with an ai of 4.1. My minumum pressure range was set to 11 and my 95% said 11.6. Any thoughts?? I just can't get any consistancy with anything. I just so discouraged.

I would try 2 weeks at my the PSG recommended pressure.

The S8 is programmed not to respond to apneas appearing above a pressure of 10. It doesn't respond to hypopneas at all. It does respond to flow limited breaths and to snores. Your breathing pattern may simply be of a type the Autoset doesn't understand or respond to properly.

What was your PSG pressure?

If you get nowhere with set pressure, then you may want to consider a different APAP.

[Guest]

Jason1975, I have the same problem and I know how frustrating it can be when you're doing everthing you can. I have been told with the ResMed machine to pay more attention to the AI than the AHI because of the way the ResMed scores hypopneas. Still I know your AI is not in the range you want it to be. I am on Spontaneous Mode with pressures of 24/20 and I have days when I meet the target, but not consistently.
Sorry, no answers, just wanted you to know you're not the only one out there.

I'm glad I'm not the only one struggling with this!! I am so frustrated because I can't get any consistancy to be able to determine anything. I've kept my range at 10 - 20 for a couple months and my numbers are all over the place. My leak rates are consistantly almost non-existant. That's the only thing that is consistant. My prescribed pressure was originally 10 and I have just recently had another titration study. They confirmed 10 was supposedly good enough. However, my numbers are all over the place. My 95th percentile pressure is always at least 11 but sometimes up to 13 or 14 some nights. My numbers aren't any better though regardless. Can allergies make you have an increase in pressure needs? I do have bad allergies but am on Zytec.

[Jason1975]

Sorry, forgot to sign in before I posted.

[DoriC]

What ozij said! Keep us posted.

[ifrimmel]

HI

Leaks!!?? First place to start looking - have you looked at your detailed leak data - make sure it's all under the line?

In my experience (which is substantially less than the amount of time that you have on the hose - so .. YMMV ) - when the machine is "autoranging" it will try to compensate for leaks which then creates more pressure and more leaks - which creates more pressure and more leaks - etc etc - if you are sleeping and not aware of what's happening it accumulates in the data and shows up as AHI's ..

For me - a tighter range at higher pressure gave me better result - it DOES help being able to look at the data.

[ifrimmel]

I've been struggling with trying to keep my AHI under 10 ever since I was put on cpap almost 2 years ago. I have an AutoSet II on auto mode. My pressure settings I had set from 10-20. It seems like I go in spurts. I can have ahi's of 8-10 for a few months straight and then all of a sudden they jump from 14-20. Could allergies cause this or what? I've been trying different ranges and it seems like my machine works better if I have my min. pressure close to my original prescribed pressure. But then again, other nights I think the opposite. When I have my minumum pressure set at 8, my 95th % is like 10 something with high ahi's. When I have my minumum pressure set at 10, my 95th % usually is in the 11 range. When I have my minumum set at 12, sometimes my 95th % stays at 12 and sometimes it goes up to like 13 or 14. Last night, my ahi was 21 with an ai of 4.1. My minumum pressure range was set to 11 and my 95% said 11.6. Any thoughts?? I just can't get any consistancy with anything. I just so discouraged.

I would try 2 weeks at my the PSG recommended pressure.

The S8 is programmed not to respond to apneas appearing above a pressure of 10. It doesn't respond to hypopneas at all. It does respond to flow limited breaths and to snores. Your breathing pattern may simply be of a type the Autoset doesn't understand or respond to properly.

What was your PSG pressure?

If you get nowhere with set pressure, then you may want to consider a different APAP.

Ditto that !

[Jason1975]

As I said before, my leaks are under control. I also have resscan and check my data every day. My leaks are between .00 and .06 usually. My PSG is 10 and I was on that for most of my time on cpap. I just recently got an auto but used to have an Elite II. My AHI's at pressure 10 averaged between 12 and 18 a night. AI's between 1 and 4 per night. This is the main reason why I got an auto. I think when I go into rem, my pressure needs to be increased. But, because of the A10 algorithm, its not getting them every time. So, I've been bumping up my minimum set pressure, but I can't get anything consistant. Sometimes my readings are good (for me) and then the next night it will be terrible. I like consistancy and right now I'm just not seeing it.

[KatieW]

Since the S8 does not differentiate between obstructive and central apneas, it could be that some of your AI are centrals.

When I switched to the S9 in apap mode, I found that my apneas were mostly centrals, and that raising the minimum and lowering the maximum, thereby tightening the range helped. Also, lowering the EPR to 1 helped even more.

[ozij]

I have a similar problem with the S8 APAP -- waiting for a repeat PSG to get more info about what's going on.
Additionally, I have flow limitations that apparently make the APAP zoom way up - my pressure is less than 10, and my Purtian Bennett machine used to show I got more central apnea above 8. So I'm using the S8 at fixed - looking for the pressure that will give the most consistent sleep quality -- which in my case is correlated with time spent in apnea.

I can't use the HI as an indicator of much -- it will increase when I'm tossing and turning, which has nothing to do with obstructions.

ResScan statistics has a "time in apnea" measure, reporting the amount of time spent in apnea. I use that as an indicator -- shorter is better.

[Jason1975]

ResScan statistics has a "time in apnea" measure, reporting the amount of time spent in apnea. I use that as an indicator -- shorter is better.

That's what I use as well. My average time is between .6 and 1.5 % time in apnea.