Problem with AHI Pattern

[languageusa]

I had a comprehensive overnight polysomnography done in May 2012 and was diagnosed with sever obstructive sleep apnea. The overall AHI was 62.5. During the second overnight sleep study (CPAP titration) at a CPAP pressure of 13 cmH20 the events per hour decreased to 0 (zero).

I started the CPAP therapy at the beginning of September. During the very first week the so called auto-trial therapy mode was used. This mode delivers CPAP therapy while automatically adjusting the pressure level to meet patient’s needs. At pressure levels up to 15 my daily AHI numbers were from 1.1 to 8.2 with the average weekly AHI of 4.1, and so the 90% pressure of 12 was calculated and locked-in thus becoming the constant pressure for my subsequent CPAP therapy.

Now is the problem. During the 6 week period that followed my daily AHI numbers were in the range of 12 to 35; for the last 2 weeks I am getting primarily 20-25 and higher. No air leaks are detected by the system.

If my AHI during the titration process was brought down to zero with the pressure of 13, and if during the recent auto-trial week of the therapy, with the 90% pressure of 12, my average weekly AHI was 4.1, then how come I am now having AHI levels of 12-35 under the same pressure of 12? What are the reasons for that? I am totally perplexed.

I may be seeing my doc only in a month, unless I find another specialist whom I can talk to (the current one is of little help). In the meantime, I need some help from people who may understand the issue and are kind enough to share their knowledge with me. Thank you so much in advance.

[ughwhatname]

I am very similar to you. Testing at 63 events per hour, and was titrated to 11, though they didn't get enough time to see that number is REM sleep, so mine range was set 4-14. I've hit 13.2 once, but otherwise, 12 and below. For autoset, I think I read that the range is at least two above and two below. I don't know the benefits of auto versus straight CPAP. Seems you would benefit from a higher number, no doubt.

If it were me (who is no doctor), I would want to stay in auto-mode. If the higher pressure is not needed, you won't get it, so I fail to see the harm in that. Its only logical that a higher upper end is probably warranted.

I had a comprehensive overnight polysomnography done in May 2012 and was diagnosed with sever obstructive sleep apnea. The overall AHI was 62.5. During the second overnight sleep study (CPAP titration) at a CPAP pressure of 13 cmH20 the events per hour decreased to 0 (zero).

I started the CPAP therapy at the beginning of September. During the very first week the so called auto-trial therapy mode was used. This mode delivers CPAP therapy while automatically adjusting the pressure level to meet patient’s needs. At pressure levels up to 15 my daily AHI numbers were from 1.1 to 8.2 with the average weekly AHI of 4.1, and so the 90% pressure of 12 was calculated and locked-in thus becoming the constant pressure for my subsequent CPAP therapy.

Now is the problem. During the 6 week period that followed my daily AHI numbers were in the range of 12 to 35; for the last 2 weeks I am getting primarily 20-25 and higher. No air leaks are detected by the system.

If my AHI during the titration process was brought down to zero with the pressure of 13, and if during the recent auto-trial week of the therapy, with the 90% pressure of 12, my average weekly AHI was 4.1, then how come I am now having AHI levels of 12-35 under the same pressure of 12? What are the reasons for that? I am totally perplexed.

I may be seeing my doc only in a month, unless I find another specialist whom I can talk to (the current one is of little help). In the meantime, I need some help from people who may understand the issue and are kind enough to share their knowledge with me. Thank you so much in advance.

[Pugsy]

Before changing anything it is advised to evaluate the individual components of the unwanted AHI.
So if you could post an image of your report it would help us to see what you are seeing on the software reports.
If your AHI is composed of a lot of "centrals" or clear airway events...increasing the pressure is not something you want to do because it won't help reduce those type of events and it might make them worse.

How to post images of reports is discussed in this thead if you don't know how.
viewtopic.php?f=1&t=81072&p=737779#p737779

A higher than we want AHI is not always treated with more pressure...need to know what you are fighting first.
Only way to know...look at the individual components of that AHI and not the overall total.

[languageusa]

A higher than we want AHI is not always treated with more pressure...

I thought that the fact that I was getting "good" (under 5) AHI during the first, auto-trial week of my CPAP therapy, says something about my responding to the CPAP therapy well. The consistently high AHI levels that followed the initial week of treatment are puzzling and unsettling.

[Todzo]

A higher than we want AHI is not always treated with more pressure...

I thought that the fact that I was getting "good" (under 5) AHI during the first, auto-trial week of my CPAP therapy, says something about my responding to the CPAP therapy well. The consistently high AHI levels that followed the initial week of treatment are puzzling and unsettling.

Hi languageusa!

Why in the world would you think things would stay the same? If you are treated well, will your health not improve?

Only the doctors are allowed to remain "willfully ignorant" of the changes CPAP therapy will produce. Why they want to I have not a clue?!?

Pugsy guides you well, to make this work you need constant feedback - your machine does have data I think - so next step rig to use that data!!

Have a great weekend!

Todzo

[Xney]

You need to see what type of events they are, first. Are they obstructive or central?

[Pugsy]

The consistently high AHI levels that followed the initial week of treatment are puzzling and unsettling.

So what changed? If good for a while when first starting cpap therapy...what changed? Something did.
It is important to identify what you are wanting to fight or reduce. A higher AHI than normal doesn't automatically mean that a higher pressure is needed. Especially since the first few nights were acceptable. Even if the first few nights had not been acceptable...you still need to understand what you are trying to do.
If you have an AHI of 6 and the majority of it is central in nature...raising the pressure is unlikely going to help and might make things worse. You have the data available...use all of it and not just a single AHI number to evaluate your therapy.