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Perception vs reality
(01-26-2015, 07:09 AM)me50 Wrote: My AHI is always great there's something that I don't really understand in their graphs and lately I haven't been sleeping good or I don't feel like I have and so I made an appointment with my respiratory therapist or whatever you call them to look at my machine and the information to see if there needs to be any changes and if it doesn't work then I will call my doctor I just never have learned much about the bi-level yet

Some of us find that tinkering with things like raising our minimum pressure makes us feel better even though AHI doesn't change.

This might be related to UARS or flow restrictions. Unfortunately, we don't really seem to do a good job figuring that sort of stuff out from the data, and trial and error may be the only way to handle it.
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There is no big secret about the bilevel machines. They are like a CPAP that has EPR on steroids. One can get more exhalation pressure relief with a bilevel, and it gives one the Easy Breathe option which I think works great and makes the pressure transitions very smooth. The other difference is that the bilevel can reach higher pressures.

What is the bilevel good for? It is normally suggested for those of us with higher therapy pressures. It may help those with aerophagia since one can use lower exhalation pressures to reduce the average pressure to the persons airway. Of course the autoset can help with aerophagia by reducing the average pressure used for the night. Bilevel might be of some help for some cases of pressure induced clear airway apneas for the same reason as above. I can not think of anything else. Hope this is some help.

Best Regards,


Admin Note:
PaytonA passed away in September 2017
Click HERE to read his Memorial Thread

~ Rest in Peace ~
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thanks PaytonA

I get all of that but I don't know how to make changes to the pressures. Also, and this isn't a Bi-Level issue, I have not perfected or even had time to figure out about the flow, MV, etc. etc. Guess we are just spread too thin right now and not in the right places lol
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I think this is where SH comes in handy. I had an original setting of 5-20, and I had a couple of nights of runaway pressure that woke me. Ironic, as this thing is supposed to improve my respiration in sleep, not interrupt my sleep by waking me up.

So I looked at my dailies for the past couple of weeks, and saw that pressure normally never went above ~13, but the two occasions where it woke me it went to 18-20. So I took this to mean that I really did not need pressure high enough to wake me, and cranked the top limit back to 14. Problem solved, AHI as low as it ever has been, consistently lower every month.

What is puzzling is that you post your pressure as a fixed number (10.8). If you have a machine that changes pressure dynamically in response to your breathing patterns, such as an APAP, runaway pressure can happen (until you corral it), but if you have a machine with a fixed pressure (CPAP) it typically will blow at the same rate all the time.

I have the same machine, and it is indeed APAP capable, but it can be fixed to be a CPAP. So it is unclear what is going on with yours if you are certain that the pressure is supposedly fixed at 10.8.
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(01-26-2015, 08:40 PM)me50 Wrote: thanks PaytonA

I get all of that but I don't know how to make changes to the pressures. Also, and this isn't a Bi-Level issue, I have not perfected or even had time to figure out about the flow, MV, etc. etc. Guess we are just spread too thin right now and not in the right places lol

Do you know how to get to the clinician menu? If you do and assuming that you are operating your VPAP auto in auto mode the 2 selections after mode will be min EPAP and Max IPAP (may be in reverse order). This is where you set the total range of pressure that you want the machine to work within excluding ramp. The settings in your profile look like you are set at max IPAP=18 and min EPAP=8. Next is the Pressure Support setting. This will set the pressure reduction for exhalation but the machine looks at it the other way around. It says how much higher it wants your IPAP pressure to be than the EPAP. A number of folks have the Pressure Support set for 4. That means that the EPAP will always be 4 cm/H2O lower than the IPAP. So, in effect, you would have an EPR of 4 and both the EPAP and IPAP will always stay within the range that you have set.

Hope this is some help.

Best Regards,


Admin Note:
PaytonA passed away in September 2017
Click HERE to read his Memorial Thread

~ Rest in Peace ~
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A little confusion: On your sidebar you specify you are running a cpap of 10.8. If that is accurate, then your machine should not have occasion to "creep up to 20." The bad mask leaks probably occur in the higher ranges. So first thing to check is what are your min/max settings on the machine? What is your median and 95% pressures when things are working well for you? Knowing those numbers you can design yourself a range that starts low, but not too low, and terminates above the area where your events are controlled. For instance, for you a nice low might be 7, and a nice max around 12?
Those are just guesses.

As to the bad leaks: As I understand it your machine only checks for leak rates periodically. So it's possible to have a "blowout," wake up, take the mask off, turn the machine off, --- and all of that without the software ever knowing anything happened. That's why when you look at your results the next day you find that the 95% leak is just fine, thank you very much.

As to checking your results daily? I did that for a long time until I got bored with it. Now I look at them every 4 or 5 days just because. I'm a firm believer in obsessing over your numbers, or anything else in life you would like to obsess about. Because after all, if you don't obsess over them, who will?

Once you get everything running about as smoothly as possible, then there is one more thing to try, and that's to smooth out the flow limit line as much as you can. That happened for me by taking my pressure up 1/2 a point beyond the point where I was getting an ahi reading of < 1 each day. Now my ahi comes in at 0 to .5 just about every day. On the occasional day it's higher, I don't worry about it because I probably forgot to check my results that day anyhow.

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my treated osa and my ahi it's good every night it's the other things that I am a little concerned about right now but I posted that in another thread so the 0P's question will not get further lost
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(01-25-2015, 05:22 PM)OpalRose Wrote: Ok, I admit to downloading my info everyday and looking at Sleeyhead and Encore to compare the numbers. Last night was one not one of my better nights. It took me over 2 hours to finally fall asleep after fighting with masks leaks, only to wake up every couple hours. I woke up at 6:00am and felt really tired, so deceided to stay in bed another hour with mask on of course! I figured that my AHI was going to be high anyway, so slept on my back in defiance. Crazy
Well after getting up and feeling a little better, I quicky looked over my numbers on sleepyhead. AHI was .4 the lowest ever, leak rates a little higher. No RERAs, no centrals, only hypopaneas. Maybe I should sleep on my back more often...just kidding!
I assume that I will probably stop checking my numbers as much when I feel I am no longer new at this.

OpalRose, I know this is an oldish post and you may not see this reply, but I have had one thought as I too check my numbers first thing every a.m to see how they do or do not correlate with my feeling and also to see if I can determine what worked and didn't...

That thought is, I think checking once a day, and especially after a bad night, for me at least, makes me feel less bad about the "bad" night...like, I'm gonna learn something from this sucker and it won't have been a bad night in vain. I don't necessarily even learn anything or come to any great conclusions, but it makes me feel like it has a purpose. And then I put the card back in my machine and happily go on my way.

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A wise doctor advised me not to check my weight, blood pressure nor anything else more than once per month unless I was keen to increase my anxiety level.

I have extended this advice to CPAP scores. Once per month over the past 15 months - sometime I forget. The PA will tell me about it during my annual review anyway.

I try to forget about it. Just strap it on at night and clean it on Saturday.
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Its probably human nature to micromanage the parsing of the data. There is somewhat of a hypochodriacal tendency for patients to do that, especially aware patients that also seek out forums.

And it doesn't really do any harm (other than the fretting over a "bad" night), but it also may not do much good and may be a waste of time.

Parsing the data helps to fine-tune things that can help bring down the numbers, but at some point it can also be overkill and has little value, especially once you get everything tuned in properly. So I think that once you get to that point, enough is enough. Never all that sensible to beat a dead horse.

And I am a little concerned with the concept of a "bad night". Last night I had a rare 3.0, while have been consistently under 1.7 for a couple of weeks, averaging 1.8 for a couple of months. But all of these numbers are considered clinically 100% treated, and even a 5 would imply normal respiration and 100% successful treatment.

Sure I'd like to have better numbers than 1.7, and maybe I'll get there eventually. But I've already won the race, just getting it down where it is right now. We all run the marathon for a lot of reasons, but only that guy from Kenya actually runs the marathon to win the marathon.

So was last night a "bad night" for me? Not really. It was an outlier, but I don't think we should be referring to that as a "bad night". Here is what a bad night is, which is every night for decades where I was untreated and had an AHI in the high 50's. Every one of those nights was a "bad" one, even if I had no idea at the time.
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