Increase or Decrease Min EPAP?

jdm2857 wrote:

RandyJ wrote:If you set max PS at 4, EPAP will not change until IPAP increases by more than 2 cm (and they will never be more than 4 cm apart). At least, that is how I understand it for Auto mode only.

With PSmax set to 4, increases in IPAP will not affect EPAP until IPAP rises to 4 cm above EPAP. After that every increase in IPAP will drag EPAP up along with it.

I should have been clearer above. I meant that since you have IPAP 2cm above EPAP when you turn the machine on, IPAP needs to rise more than 2 cm before it would have any impact on EPAP with a PS of 4.

jdm2857 wrote:It's Saturday and Dori is thinking about dancing.

Any plans for tonight?

Does Walmart have a dance floor?

jdm2857 wrote:Try inching up EPAP min to 16 and see what happens. You may even want to go up to 17 eventually.

I went ahead and tried going up from 15 to 16. Last night was my 3rd night at 16 min and I have been getting AHIs of 1.0 - 2.5 versus 2.5 - 4.0 at 15. I'm not certain if what I am seeing here is meaningful but this the kind of apnea cluster I would see at 15:


Here is the same kind of cluster at 16:


Is is just my imagination, or is the cluster of events starting with less severity, allowing more breathing between each event, and getting under control faster with the slightly higher pressure?

I see first talked about report image and have attempted to put it up for viewing. It shows in preview but sometimes it doesn't show when submitted. So your first report image is below my comments. I would like to see the most recent image after the EPAP increase from 15 to 16.
It's hard for me to form any sort of opinion based on this single report and the last image talked about I can't see.
My first suspicion for this report below is that the clusters are related to perhaps REM stage sleep or supine sleep (or maybe both).
Looks a lot like my report.
EPAP....for obstructive apneas
IPAP ....for hyponeas
CAs....we ignore since number is insignificant.

Baseline EPAP would be my first thing to look at if it were me. My thinking is a little more EPAP which I guess has been tried and an attempt to show results just gives me the word "image". If the clusters of OAs are broken up...that is what I would have suspected would happen with the increase in EPAP just a little.
I have a couple of examples of my own. I will see if I can find them.

Here's the link to my little pressure adjustment last month.
viewtopic.php?f=1&t=89894&p=826020#p826020
A little more EPAP was all that was needed to clean things up.
My AHI didn't change all that much but it did change a little and the "clutter" (snores and FLs) pointed to the pressure not being quite optimal.
My OSA issues are 98% OAs....never had many hyponeas
So with the standard rule of thumb...EPAP for OAs and IPAP for hyponeas I chose to go with the high probability that the snores and FLs were working on growing up to be OAs...so that was my reasoning for more EPAP.
My PS is 4...I am okay with 5 but anything above that and I don't sleep as well.

I don't know how much of this may relate to what your issues are or what you are seeing on your reports but the common basics as to how these machines work are pretty standard.

You changed your settings by your own choosing. Be careful...don't make too many changes too fast. There is some truth to the "give it time" speech. Remember Science 101...with experiments keep variables to a minimum so you can measure the response more accurately.
If you are going to explore changing things do educate yourself on what you are doing and why.

Thanks Pugsy. I would have responded earlier, but as you point out I had already made the change and I wanted to leave it be for a while. I think the pressure change is having an effect, but not as much as I had hoped. For now I'm just going to, as you say, "give it time."

At an EPAP min of 15 I get clusters like this:

I can't imagine it is good to have strings of half a dozen 30 second OAs hitting 30 seconds apart like that.

At an EPAP min of 16 I get clusters like this:

I'm still getting the clusters, but it seems there is more time between events and a few less total events before the machine raises the pressure enough to get them under control.

While I believe I have a basic grasp of the whats and whys you mention, my concern comes from uncertainty in how to balance the reduction of the clusters on one hand and the higher pressures on the other. Even though I have gotten myself into < 5 AHI territory, I'm sure those remaining clusters aren't a good thing. To speculate a hypothetical situation, suppose I found I could have three or four event clusters like those in the first picture and keep my average AHI around 4 or 5 while spending the rest of the night at a lower minimum pressure of 14. Alternatively, I could knock those clusters down to two or three moderately spaced events and keep my average AHI around 1 or 2 by running a higher minimum pressure of 17. Assuming I don't suffer bad aerophagia or other side effects from the additional pressure, which is the better scenario? I suspect the answer is, "Whichever one gives you the best overall results," However, I have had several knowledgeable people react negatively to my high minimum pressure setting without being very clear about WHY... enough to make me question what they might know that I don't, even if they can't explain it very well. If things were as simple as raising minimum pressure to an overall effective level, why wouldn't we all just set our Auto machines to our 90% pressure (unless it is and I'm just overthinking this)?

Pugsy wrote:You changed your settings by your own choosing.

Yep. I make my choices and I own the consequences for better or for worse.

Regarding increasing the EPAP concerns by some people. The biggest concern that comes to mind is the issue that people think that higher pressures cause central apneas to materialize. While it can happen..people can get centrals popping up because of as little as 6 cm pressure. It doesn't have to be higher pressure and higher pressures don't always cause centrals. People get scared about centrals when there often is no reason to be scared.
I often see nearly 20 cm on my bilevel reports...I don't have any more centrals because of it...pretty much the same random occasional central that I might see when my pressures don't increase at all..
There are people using Bipaps with EPAP and IPAP greater than 20 cm...with no increase in centrals.
The actual % of the population who have pressure triggered central apneas (called Complex Sleep Apnea) because the pressure treating the obstructive apnea causes the central apnea is only around 10 to 15 %....

I get clusters (like yours at 15 cm EPAP) with 8 cm EPAP on my machine...when I use 10 cm EPAP...those clusters are pretty much broken up and only occur sporadically.
Why do we get them during parts of the night and not other parts? Most likely suspects are either REM stage sleep or Supine sleeping or a combination of both. It's common for people to have more events during REM or supine sleeping and/or need more pressure at time during REM or Supine sleeping. In my case it is REM stage sleep. Sometimes the events I have in what is likely REM sleep are really difficult to prevent and other times they are easy to prevent and my pressures don't vary much.
When they are being difficult to prevent is when I see the EPAP and IPAP push 20 cm. I have wondered if Supine sleeping was involved but I spent a month with a wall built so that I absolutely could not get on my side and I still had times where the pressures went high so I don't think that supine sleeping is much of a factor in my pressure needs.
Even if it was a factor...I wouldn't do anything but just let the machine do its job but it would offer a nice explanation as to why.

Did you ever read Kenwood's thread? It's quite long now but it might interest you.
viewtopic/t87166/AHI-131---Help-me-unde ... sults.html

Regarding the 90% pressure number thing. I don't think it is the holy grail myself because I have seen it manipulated too easily.
Sure on the night's that I might push 20 cm it will be higher but I sure wouldn't want to use those higher pressures every night and all night just to deal with maybe a couple of 30 minutes sections of time where I might need more pressure.

Higher pressures can also cause an increased risk of aerophagia. When that happens we simply have to make some compromises and maybe let a few more apnea events happen to avoid severe aerophagia. It can be quite miserable and cause more problems in how a person feels than a few random apnea events that slip past the defenses.

Your EPAP of 16 report above. Really looks pretty good. That last cluster of OAs...real close to wake up time and unless I saw a lot of those clusters I think I would be happy with 16 EPAP if it were me. I still get little clusters occasionally myself but they are random and small.
If I saw those type of clusters often...then I might try just a little 0.5 more EPAP.
You will find that your AHI and events and clusters will vary from night to night with no changes in anything at all. We simply don't sleep the same each night. This is why we say to "give it time" when we make a change and want to evaluate things.
Need to look at overall trends and patterns and not go chasing events nightly with various changes.

So I think that at least on paper you are real close to optimal as far as settings go for optimal treatment. I don't see any evidence of centrals rearing their ugly head with your pressures. There simply isn't enough of them to warrant concern. We all have a few from time to time anyway and that's normal.

So my next questions....how are you feeling? Sleep quality? Feeling during the daytime? Having any issues that you feel need work? Wake up often during the night?

Pugsy wrote:So I think that at least on paper you are real close to optimal as far as settings go for optimal treatment. I don't see any evidence of centrals rearing their ugly head with your pressures. There simply isn't enough of them to warrant concern. We all have a few from time to time anyway and that's normal.

I think so as well. Originally I didn't think I should dive right in to the higher pressures so I initially set Max IPAP to 12 and logged a startling 82.2 AHI with the machine pegged at 10/12 the entire night. I increased the maximum pressure by 1cm each subsequent night and each night the machine would climb to the max pressure and stay there, but my AHI numbers fell steadily for a week until I got to 20. I ended up with the machine wide open, 90% pressures of 18/20 with infrequent spikes as high as 21 or 22 for brief periods, and AHIs in the single digits. The biggest problem I had was going to sleep at low pressures and waking up shortly afterward feeling like I had a leaf blower in my face. I raised the minimum EPAP to 15 on the reasoning that it would limit typical pressure swings to 4cm or so and that seemed to work well enough that I left things alone and was happy getting AHIs around 4. It wasn't until I got into the software and saw the clusters of events that I thought perhaps I should improve things by targeting a more effective Min EPAP.

Pugsy wrote:So my next questions....how are you feeling? Sleep quality? Feeling during the daytime? Having any issues that you feel need work? Wake up often during the night?

To be honest, being on the machine and in the effective treatment range at all is such a big and new change that I have difficulty evaluating the smaller differences that occur within the range of effective settings. I am waking up on my own most days, and waking up when my alarm goes off instead of sleeping through it on the others. I do awaken occasionally for brief moments during the night, but from what I understand that is normal for most people. I don't fall asleep watching TV or even feel the need to take naps during the day, let alone get that overwhelming desire to just lie down on the floor and nap like I used to. Unexpectedly, my coffee and soda cravings have dropped dramatically, probably because I am not craving the stimulant effect of the caffeine. I may be experiencing minor aerophagia, but then again it could just be the Mexican food.

Overall, other than perhaps eventual fine tuning of pressure and flex settings for optimal numbers, my only challenges lie with finding the most comfortable interface between the machine and my face. (I ended up with a lot of masks with my used machine) The Mirage Quattro either leaked on the sides of my nose or gave me angry red sores on the bridge. The F&P Forma and FlexiFit were okay on my nose, but seemed to sprout random leaks here and there whenever I moved my face no matter what I did. The Amara was like a compromise between the two extremes of the Mirage Quattro with only minor leaks at the sides of the nose and only minor soreness on the bridge. Lately I have been trying a Liberty Hybrid and am pleasantly surprised how well the nasal pillows perform under pressure. The smaller seals around the mouth and the nose seem to make the seal more resistant to sprouting random leaks. I know I tend to open my mouth at night, but the effectiveness of the nasal pillows on the hybrid have me wondering how well a nasal mask and pap cap combination would work. It would most likely be more comfortable that the full faces and hybrids if I didn't end up blowing air out my mouth.

Thank you all for taking your time to participate in this community and offer the benefit of your experience to others.