Question About Lowering AHI

I've only been using my equipment for about a week. I've managed to download the Sleepy Head Program and have actually imported a little bit of data. At some point soon, I'll attempt to upload data when I have a question.

In the meantime, I've had to rely on "My Air" for most of my data. The program says I'm attaining nearly 100% with my treatment, but I'm wondering what things will generally lead to attaining a lower AHI. My diagnosed overall AHI was 23; my doctor prescribed a pressure range of 5-9; my average has been 7.5; my average AHI has been 5; and, my mask seal averages a lost of 6 L/min. I would like to do better than an AHI of 5 even though "My Air" thinks 5 or less is great.

Generally speaking, what things can be done to effectively lower the AHI? It doesn't seem that a pressure adjustment is called for since I've never exceeded 8.5, so what's left? I apologize for not having voluminous charts and graphs at this point. I'm just wondering if I should simply accept that I'm getting excellent results (as far as some are concerned) and leave it alone. thanks

Try raising the min pressure to 6-7.

LSAT wrote:Try raising the min pressure to 6-7.

OK. So by raising the minimum (even though I've never gone above my prescribed maximum of 9), that should cause me to go above 9--and/or I would spend less time near the minimum, thereby improving my AHI? Certainly not arguing. Just trying to understand how the whole thing works. thanks

Comfortably Numb wrote:OK. So by raising the minimum (even though I've never gone above my prescribed maximum of 9), that should cause me to go above 9--and/or I would spend less time near the minimum, thereby improving my AHI?

Raising the minimum won't cause you to go above 9. All it does is help the machine get to where it needs to go in a bit more timely fashion.

While the knee jerk reaction to a higher than we might want AHI is "more pressure"....I prefer to know what that AHI is made up of first before doing the "more pressure" thing.

More pressure is most likely indicated if the bulk of that AHI is obstructive in nature (OAs/hyponeas) but if the bulk of the AHI is central in nature then more pressure won't help at all and might even make things worse.

Oh..the pressure number reported at MyAir isn't an average pressure ...it's what they call a 95% pressure number and all that means is you were at OR BELOW that number for 95% of the night. People often forget or don't realize the "or below" part of the definition of a 95% number.
Same thing with the leak number...it's a 95% number...so at or below that number.

Raise the max to e.g. 15 and see if the machine even once gets up there... you've prevented that from happening by capping it at 9 which is pointless. But do raise the low end (the meaningful one) by 1-2 at least. Your doctor (like so many unfortunately) doesn't understand how the machine works or he wouldn't have set a high pressure so low.

Your doctor (like so many unfortunately) doesn't understand how the machine works or he wouldn't have set a high pressure so low

I think 9 was the pressure at which I achieved the best results on the night of my sleep study. That's the only reason (other than the lack of understanding you mention) he set the max so low. It makes sense to me that a higher minimum means less time ramping up to the maximum and therefore more time spent at a higher overall pressure. I don't see how adjusting the maximum upward, however, will make me go where I've never been before--not that you said I would. And, almost all of my apnea is obstructive.

Again....I wouldn't go increasing pressures until I was for sure that the problem I was wanting to fix is fixable with more pressure.

While the odds are that more pressure is probably what is needed...without more information (like what that AHI is made up of) we don't know for sure that more pressure is needed...AHI event categories is easily available...there's no reason or excuse to guess in this situation.
More pressure in the face of all centrals...won't fix a thing and could make things worse.

So....what is the AHI composed of? Then a decision is made as to whether or not more pressure is needed or would even help.

How about sharing a copy of the software report so we don't have to guess? I don't like guessing if there is any other way to get around it and in this situation even without software reports...event categories are available on both the machine and any online reporting data.
viewtopic/t103468/Need-help-with-screen-shots.html

And, almost all of my apnea is obstructive.

The minimum is the most critical pressure setting when dealing with obstructive stuff.
Without seeing what your pressure graph is doing....it's really hard to offer more than a guess but I would think a 2 cm increase in the minimum would likely be a good starting point given what you have just said and if the AHI is primarily obstructive and is running in the 4 to 5 range all the time.

As for the maximum...if you never hit the maximum it doesn't matter if it is set to 9 or 20.

I'm with pugsy on this one.

Until I know more about what that AHI is made of, I am cautious about making a knee-jerk recommendation to raise either or both the min and max pressure settings.

And before recommending that a new PAPer open up the top pressure wide open, I myself want to know whether the person has had any problems with aerophagia. And what (if anything) drives their machine to increase the pressure substantially.

Finally, I would also urge that Comfortably Numb make small adjustments to the pressure rather than large ones---particularly since we have no information about whether s/he is having serious problems getting to sleep with the machine.

I made one small but significant change last night, and it seems to have resulted in over a five fold decrease in my AHI. For starters, I boxed up the Amara View for return to the DME. Then, I used my N10 nasal mask for the entire night. I am still unable to post a screen shot but this is what this morning's data revealed: AHI = 0.66; Large Leak = 0.3%; Clear Air Way = 0.13%; Obstructive = 0.13%; Unclassified Apnea = 0; Hypo = 0.4%; RERA = 0.13%. No adjustments in the minimum pressure were made.

Could it be that a simple change in masks could have caused such a radical reduction in AHI?? All other variables remained the same......

Comfortably Numb wrote:Could it be that a simple change in masks could have caused such a radical reduction in AHI?? All other variables remained the same......

Yep. Sure could be something that simple.
You may have needed more pressure with the full face mask than you do with the nasal mask...if the bulk of the higher AHI was obstructive/hyponea. Quite common really. Not sure why unless it is the way that full face masks end up causing the lower jaw to get positioned making the airway maybe a little more narrow. I know people needling 2 or 3 cm more minimum pressure when using a full face mask to get the same AHI results as they get with a nasal mask.

So yeah...it could be that simple or it could be that last night was a fluke for some unknown reason.
We never totally base anything on just one night...good or bad.

Comfortably Numb wrote: Could it be that a simple change in masks could have caused such a radical reduction in AHI?? All other variables remained the same......

Which mask is more comfortable? Which mask is easier to sleep in?

I'll piggy back on Pugsy's comments: Let's hope the mask switch fixes the problem, but do be aware that one night is not a guarantee. Still, one night is better than 0 nights.

I should mention one variable that completely slipped my mind. Last night was the first night that I waited until the very minute I wanted to go to sleep to turn on the machine. In the past, I've been lying in bed reading for up to an hour with the machine on and the mask in place. I assume that the pressures were low during that hour since I wasn't in sleep mode (or does this machine ramp up regardless??). The nasal mask is definitely more comfortable and much easier to sleep with. I shied away from it initially because I had so many mouth air explosions during the sleep study and ended up with a sinus infection due to 0 humidity and a nasty hospital virus. Also, I think they were testing me at higher pressures during the study. At present, I have a little break through and dryness but absolutely nothing to compare with the sleep study. I may not even need a chin strap!

Comfortably Numb wrote: I've been lying in bed reading for up to an hour with the machine on and the mask in place. I assume that the pressures were low during that hour since I wasn't in sleep mode (or does this machine ramp up regardless??).

Your minimum pressure is 5 and the machine won't increase the pressure within the current parameters unless it senses some sort of obstruction going on which we assume wouldn't happen while awake but sometimes the machine can get fooled. Not often though.
Now if you were using ramp...and it started at 4 while you were reading it would go up to 5 but that's it.

Oh...one other point so that you know the way things are reported and the values
on the LCD screen...these

Comfortably Numb wrote: AHI = 0.66; Large Leak = 0.3%; Clear Air Way = 0.13%; Obstructive = 0.13%; Unclassified Apnea = 0; Hypo = 0.4%; RERA = 0.13%.

Only the Large leak number is a percentage...the rest of the numbers are all hourly averages.
Clear Airway is Respironics term for central apnea.
AHI is the overall hourly average and is composed of Obstructive apneas, hyponeas and Clear Airway/Centrals.
RERA is not part of the AHI on the LCD screen.

hum...I also get the AHI from myair, I need to get the detail info from sleepyhead. After I read this, I worry about if my AHI from my air is accurate or not. I have a AHI of 44 at the sleep study. My doctor set the 7 to 15, with 3 increase. My average AHI always keep within 2 since I use the air curve auto. Since it's average AHI, I would think at least non of the AHI will reach 5 based on the math, right? Is that a true number or I should get more myself? My doctor did check the SD one time, he says it's good.

The AHI as shown on the MyAir site is accurate. The figure is an average for the night. You could conceivably have 10 events in one hour, and then nothing the rest of the night and your AHI would be 1.25 assuming you slept for 8 hours. It is quite unlikely this would happen, but it is possible.