Can an increase in minimum pressure cause Central Apneas

Hi,

I am not sure if 4 days is a good judge of things but;

I recently increased minimum pressure from 4 to 4.6 and find my AHI has gone from 2.5 to 3.5

I had been at 4 since I started in April.

It is the only change I've made in these 4 days.

At 2.5 I am clear headed at 3.5 I start to get a slight headache

I am going to drop it down tonight to 4.2

Thanks in advance!

4 days is not a good judge. An AHI of 3,5 is great for a new user. Don't worry about Centrals unless you get DOZENS in clusters.

I recently increase minimum pressure from 4 to 4.6 and find My AHI has gone from 2.5 to 3.5

Have you ever posted some of your daily detail charts for members to view?

Day_Dreamer wrote:Hi,

I am not sure if 4 days is a good judge of things but;

I recently increase minimum pressure from 4 to 4.6 and find My AHI has gone from 2.5 to 3.5

yes, in some poeple, higher pressure can cause central apnea to appear.

*generally* that's at pressures over 10cm, and only in roughly 1 in 7 people.

your AHI encompasses a lot of things, you should pull detailed data off your machine and examine it.

LSAT wrote:4 days is not a good judge. An AHI of 3,5 is great for a new user. Don't worry about Centrals unless you get DOZENS in clusters.

LSAT,

I had been getting 2 and below for a long time and it started to creep up. It got to 6 and I made some changes to my max pressure (14 down to 10) and it dropped to 1.5. Now its been creeping back up. I am new but, once I experienced a few night of AHI below 2 I can not go back to greater than 4.

You are right though 4 days is not a good judge. I left my minimum pressure alone and this mornings AHI was 3.1

ChicagoGranny wrote:

I recently increase minimum pressure from 4 to 4.6 and find My AHI has gone from 2.5 to 3.5

Have you ever posted some of your daily detail charts for members to view?

Hi CG,


I have not posted yet

I had some issues with my Mac which I fixed last week (finally)

I really need to! I am meeting with my sleep doc next Thursday and would like to be informed. Last time the NP looked at my useage only.

I never completed an in lab test (due to anxiety) only a home sleep test

I will attempt tomorrow

THANKS!!

palerider wrote:

Day_Dreamer wrote:Hi,

I am not sure if 4 days is a good judge of things but;

I recently increase minimum pressure from 4 to 4.6 and find My AHI has gone from 2.5 to 3.5

yes, in some poeple, higher pressure can cause central apnea to appear.

*generally* that's at pressures over 10cm, and only in roughly 1 in 7 people.

your AHI encompasses a lot of things, you should pull detailed data off your machine and examine it.

Thanks Pale Rider

As mentioned in my response to LSAT I was 1 of the 7 who gets centrals from high pressure.

I have read that EPR could cause centrals. So I was concerned an increase in my min pressure could have the same results

Bear in mind that the occurrence of a few centrals being flagged are considered "normal" and it's only when the centrals start occurring in large numbers or causing a problem that we start worrying about them.

It's common for some "centrals" to be flagged while awake or semi awake...we don't worry about these at all.

It's also "normal" to have what we call sleep onset centrals when transitioning in the sleep stages. Most often from awake to first sleep stage. Unless they occur in large numbers...cause desats...cause a lot of awakenings...we don't worry about those either.

So not all central flags are related to pressure or an increase in pressure. If you are one of the minority of cpap users who do develop centrals as a response to cpap therapy you would still need to have more centrals than you are having right now and that's assuming none of your "centrals" are awake/semi awake centrals. Like 5 per hour, every hour, every night...type of thing.
If the bulk of your central flags are in close proximity to known awake times then there's a good chance they aren't the real deal anyway. This is where it comes in handy that you learn to evaluate your software detailed daily reports.

Finally even if your centrals are indeed the real deal and directly related to pressure increases there are some things that can be done to try to reduce the number (should the number warrant reduction) and sometimes the centrals will go away on their own as the body gets used to cpap pressure in general.

Until you look at your detailed data, you don't even know if you are having central. If you are, could they be clustered around wake ups. It could be Hyponeas. It could be OA while sleeping on you back.
Without looking at the details you just don't know.

bwexler wrote:Until you look at your detailed data, you don't even know if you are having central. If you are, could they be clustered around wake ups. It could be Hyponeas. It could be OA while sleeping on you back.
Without looking at the details you just don't know.

Agreed

I am working from assumptions

But once that pressure was dropped from 14 to 10 the events subsided and stayed low every day for a few weeks.

Pugsy wrote:Bear in mind that the occurrence of a few centrals being flagged are considered "normal" and it's only when the centrals start occurring in large numbers or causing a problem that we start worrying about them.

It's common for some "centrals" to be flagged while awake or semi awake...we don't worry about these at all.

It's also "normal" to have what we call sleep onset centrals when transitioning in the sleep stages. Most often from awake to first sleep stage. Unless they occur in large numbers...cause desats...cause a lot of awakenings...we don't worry about those either.

So not all central flags are related to pressure or an increase in pressure. If you are one of the minority of cpap users who do develop centrals as a response to cpap therapy you would still need to have more centrals than you are having right now and that's assuming none of your "centrals" are awake/semi awake centrals. Like 5 per hour, every hour, every night...type of thing.
If the bulk of your central flags are in close proximity to known awake times then there's a good chance they aren't the real deal anyway. This is where it comes in handy that you learn to evaluate your software detailed daily reports.

Finally even if your centrals are indeed the real deal and directly related to pressure increases there are some things that can be done to try to reduce the number (should the number warrant reduction) and sometimes the centrals will go away on their own as the body gets used to cpap pressure in general.

So I should probably hold off on that new AVS machine

I need to post my data. I am a bit of an idiot when it comes to these computer things

Day_Dreamer wrote:So I should probably hold off on that new AVS machine

I don't see you needing ASV (or even getting close) at this time. Even if every one of your centrals was indeed related to pressure there simply isn't enough of them happening at this time.

What issues are you having with the software? Is it the software itself or the posting of images?

Day_Dreamer wrote:... I made some changes to my max pressure (14 down to 10) and it dropped to 1.5. Now its been creeping back up. I am new but, once I experienced a few night of AHI below 2 I can not go back to greater than 4.

You are right though 4 days is not a good judge. I left my minimum pressure alone and this mornings AHI was 3.1

Do you find it difficult to exhale with the pressure at 14cm?

You can also lower your AHI by moving your lower pressure closer to 10 say 6 or 7.

You can also lower your AHI by moving your lower pressure closer to 10 say 6 or 7.

Won't help the AHI if the AHI is primarily central in nature to increase that minimum and for someone with a history of pressure triggered centrals it cold possibly create more centrals.
OP has a history of centrals at higher pressures and that's why the maximum setting was reduced from 14 cm down to 10 cm...just so that didn't happen.

Day_Dreamer wrote: So I should probably hold off on that new AVS machine

this is what needing an asv looks like: