pressure rising?

After being titrated at 9 during sleep study 7 months ago, and switching to autopap 2 months ago my pressure is rising to 15.6 as oppose to the usual 12.4. My ahi, ai,hi, are on the rise along with mask leak........but I feel more rested today. Any ideas on what's up with this would be greatly appreciated. I see my sleep dr. next week for the 2nd time.......Ellen
P.S. as you can see my dr. is very, busy??????????

Ellen -

Why is your pressure going so high?

What is your upper limit set to in APAP? it should not be set to more than 3 or 4 cm above your titrated pressure.

- roberto

Hi Ellen,

To continue with what Roberto mentioned, could you please give us a little more information on your settings.
It could be any number of things, not the least of which could be a need for more pressure on some nights.
Do you have the "Settling" setting programmed?
Could be mask leaking.....which is also going to be higher with increased pressure.
Snoring.....

Glad you're feeling good though.

Best wishes,

Den

hi,
when i first got the resmed vantage it was wide open at min 4 max 20 the first few nights it went from about 11 to 12.8 . all my ahi,ai, hi, stayed below 5. then after joining the forum i set the maching at min.7 max 13........well my dr, called and told me to keep it wide open that was why she agreed to the auto machine.........she had me on straight cpap at 9 with the resmed elite........and after 3 months of only 4 hours of sleep per night i received the auto machine. i don't think i should keep it wide open with the pressure on the rise????????? thanks........ellen

The doctorb is ... umm ... well I'll say it... insane. 4 - 20 is not a good idea.

I said it before and I'll say it again, if your sleep patterns include any central based events and/or you are at risk of them, Resmed's autopap algorithm is the wrong machine for you. One hint that is happening is when your 95% pressure is a moving target, it means the machine is mis-reading your SDB events (e.g logging central events as obstructive).

The higher the pressure goes the more events you will appear to have, most likely an increase to HI's more so than AI's.

Drag out your last lab PSG or titration, look for any CA or MA events noted on that report. IF you have any of those events noted you have the WRONG autopap machine.

The solution is to go back to your lab titration value (9.0cm?) then you MUST set the Max. pressure to that value to prevent the machine from runaways from falsely reading your events.

It works like this... as the autopap runs it detects a snore, it increases pressure, the longer snores exist the more pressure is delivered until machine starts triggering central hypopnea/apnea events, since the machine can NOT distinguish between central and obstructive it "thinks" it is seeing obstructive events when they really are central. So the cycle continues with the machine increasing pressure triggering more events and you SEE the pressure continually rising with elevated HI levels. AI's may also increase if the duration matches that of a obstructive apnea.

Any way you look at it, the Resmed machine is bad news for your treatment. Like I said, you can get around that problem by carefully controlling the Max. pressure and using a set Min. pressure of 6.5cm, using a 30-minute Settling timer also helps.

I've always tried to avoid labeling that machine a POS, but over and over patients come here with the same problem as yours. Some can swear by that machine's algorithm all they want, but if your SDB events get misread by it which triggers increasing pressure it is junk.

You want to see your numbers drop?

Set the Min. pressure to 6.5cm
Set the Max. pressure to 9.0cm
Set the Settling timer enabled and set for 30-minutes.

When you start off, hit the settling button and go to sleep, I'll bet your numbers will be lower if leak is under control. If you want to go off trying other settings then come back and say it didn't work then you are on your own.

Too bad you didn't have a Remstar Auto w/Cflex to trial, it would treat your condition much better than the Resmed.

The Respironics machines will also pressure-runaway chasing snores. :/

hi snoredog, i agree with you 100 percent.. i will change the settings tonight.......should i try to get the respironics machine or is jcraig correct about getting the same runaway results..........thanks ellen

[quote="JCraig"]The Respironics machines will also pressure-runaway chasing snores. :/

Snoredog wrote:You are WRONG, the Remstars have a limiting control circuit for snores it will pause if snores persist over 3 pressure increases based upon a time frame.

Read the patent if you don't know how it works.

Must be another reason that my machine will constantly raise the pressure in line with what it thinks are snores, then.

In reading SnoreDog's post, that's about what I experienced when I ran my Auto in a range. I set my range from 10 to 15. The snores DID seem to increase the pressure, but in 8 nights, it only got to 15 for 1 1/2 minutes on one night. It either snuffed out the snoring or went up the 3 pressure levels and stopped.....usually at 13 or 14. It lowered my snoring, but my AHI was a little higher than on single pressure (between 1.0 and 1.5). I'd prefer the lower AHI.
One thing I HAVE noticed with my setting at 11 now is that my Variable Breathing numbers are remarkably consistent.....whatever THAT means. AND, my Snore Index is very low and also pretty consistent (for me). AHI is generally under 1.0. I think I've found my ideal setting....for now.

Den

[quote="Wulfman"]In reading SnoreDog's post, that's about what I experienced when I ran my Auto in a range. I set my range from 10 to 15. The snores DID seem to increase the pressure, but in 8 nights, it only got to 15 for 1 1/2 minutes on one night. It either snuffed out the snoring or went up the 3 pressure levels and stopped.....usually at 13 or 14. It lowered my snoring, but my AHI was a little higher than on single pressure (between 1.0 and 1.5). I'd prefer the lower AHI.
One thing I HAVE noticed with my setting at 11 now is that my Variable Breathing numbers are remarkably consistent.....whatever THAT means. AND, my Snore Index is very low and also pretty consistent (for me). AHI is generally under 1.0. I think I've found my ideal setting....for now.

Den

So if I'm understanding this correctly ...

The RemStar auto is a much better machine if you use it to titrate your pressure at home in the absence of lab equipment and a qualified tech.

The ResMed auto is OK if you already know what your titrated value is which allows you to safely set the upper limit and you are simply using the auto to minimize the overall pressure needed during a normal sleep period.

- roberto

I too found out about chasing snores, but the cure it simple set the top limit to the best pressure for you in the cpap mode, then it can't go past that level and you still get the best treatment.

The problem is the machine treats snores, like it supposed to. Increasing pressure to stop the snoring, the rub comes from the higher pressure, causing more mask leaks, so you keep snoring. and the machine keeps trying to do it's job, by increasing the pressure.

If the mask wouldn't leak, the pressure would stop the snoring, and the pressure would go back down. However we end up with the dog chasing it tail. The answer is to lower the top pressure to our best treatment pressure. (Help the dog, by holding it's tail so it can catch it).

It's a simple cure that works. We all make different levels of sounds (Snores), when we sleep, what we need is a dial to crank in the level of snoring that each of us is best suited to. That dial doesn't exist, and if it did, a lot of folks would have it turned the wrong way, the more knobs the higher chance of poor treatment. Masks type make a big difference in how treatment works, but that's a different story. Jim

Snoredog wrote:If you recall there was at one time here a Respironics auto titration DME training "program" (autoalgorithmtraining.exe) that simulated how the Remstar Auto-pap algorithm functioned (think it was taken down at the request of Respironics Prod. Mgr.).

Do I dare admit that I HAVE a copy of it? I think I went through part of it, but that's been quite a while back.

Den