Pressure Changes & BiPap Auto

[MS69]

Usually Im very compliant with therapy but I am having some issues for the past week or so. Ive been having a hard time sleeping, waking every hour or 2, really unable to get a good nights sleep. Previously, no problems at all. My pressure requirements have change in the past (pre-BiPap Auto) with lifestyle changes like weight loss or increased exercise. The Auto is set to a range of 7 to 16. Would changing it help? Does the range need to be narrower or wider? Should the Auto be able to detect any pressure needs change and be able to adapt to it with no resetting? Any advice is appreciated

[bdp522]

What was your titrated pressure? If you were titrated at a pressure of 11 or 12 or higher, the machine may not be getting enough time to respond to events. Do you have the software? Without it it's hard to find the problem. What was your machine set at before? I found it difficult to sleep with my machine on auto. I have to use cpap mode.

Brenda

[MS69]

Brenda-

I dont have the software. The Ipap was 16, Epap was 7. Is that what your asking? Im starting to get a little punch drunk now so I might not be clear. I can get data off the smart card from this RT I kind of deal with but I dont have the Encore Pro at home and it looks like that avenue is closed. This always happens when I make a change in lifestyle and its a lagging indicator. Ive been lifting weights and riding a bike every day, want to lose weight. It feels like one day my body says whoa your getting too much air and its off to No Sleepsville. At least thats what I think anyway, 98% of the time I have no problems whatsoever. Im just an amatuer and you guys are the pros. I wish I had medical insurance but I dont.

[bdp522]

When you had your sleep study they should have come up with one pressure that they felt you did best at, do you know what that pressure was? If you don't already have it you need to get a copy of your sleep study. The info on it is very important. Lacking that, I think a narrower range may be better for you. If it were me, I'd raise the bottom pressure to 8 or 9 and see if that made a difference. Without the software you don't really know where your problem is.
Hopefully someone with much more experience will jump in here to help.

Brenda

[MS69]

Brenda, thanks for the replies. My sleep study results would be useless I would think. It was over 6 years ago. I will try the narrower range. Can I ask whats the logic behind the narrower range? Not saying your wrong, just the reasoning behind the answer, so I can learn more.

[bdp522]

I'm thinking that if you narrow the range it will take the machine less time to respond to the events that may be occuring. If your machine is set to 7 and you need a pressure of 14 to stop(or prevent) the event, the machine doesn't just go right to 14, it does it in steps. If you start at 9 it has less steps and will get to the needed pressure sooner. Like I said with out sleep study info or software it's just a guess.

Brenda

[Wulfman]

Are you running it in a straight Bi-PAP mode?.....or do you have auto ranges set for min and max EPAP and IPAP settings?
An EPAP of 7 sounds pretty low to me, too......from an IPAP of 16. You could be having events and it's obviously disturbing your sleep.

Also, without the software, you're shooting in the dark.

Den

[Goofproof]

You could maybe reset it to the settings you were using on you old machine for a few days. I wonder why without Ins you had to have a BiPAP, when you treatment was ok with what you had BiPAP introduces more complex treatment, without software you need bulletproof shoes. Jim

[Snoredog]

that is the WRONG machine to be "narrowing" the range on. Does NO good to make a change to the machine unless you know what the change will do.

You only want to increase EPAP if you are having residual OA's. You only want to increase IPAP if you are having residual Hypopnea. The only way to know that for sure is to observe a Daily report. Because of the type of machine you then have, you need to understand the logic behind how the machine responds.

On that machine there is PS or Pressure Support, get that set too high or wide and you actually limit how the machine can respond to particular events. Sure it might give you greater seperation between IPAP and EPAP pressures but that isn't going to treat you or make you feel any better.

You are waking up after 2hrs? Ask yourself why: If xpap is allowing you to get into REM, that is where you probably are when you wake up. REM is also where you are more likely to have an apnea event since you go through cycles about every 90 minutes. I haven't seen your daily reports, so I have no idea what your SDB activity is during that time and what your 90% pressures have been running. You are more likely to spend more time in REM as the morning approaches.

At this point, I'd say your Minimum EPAP is fine, your max IPAP is probably also fine, I suspect your PS setting is set too high/wide like at 8cm. This means when you turn on your machine pressures start at 7cm EPAP and 9cm IPAP. With PS=8, IPAP will move up as Hypopnea is seen, if very few apnea is seen then EPAP will remain at 7cm. If apnea is not seen until you get to REM there would have to be enough Hypopnea seen during that time for EPAP to ever move higher (because of a too high a PS setting). '

Now, if PS=4cm, the you would still start off sleep at 7cm EPAP and 9cm IPAP but once IPAP got 4cm higher than EPAP it would begin to "pull up" EPAP from 7cm to 8cm automatically. With a PS=8cm, it wouldn't begin doing that until it reached the end of the max PS of 8. So for you the patient you will be setting there with a high IPAP and a low EPAP, nothing I'd want to write home about.

So the point is, instead of increasing pressures, increasing noise, increasing leaks, increasing discomfort of therapy that goes along with those increases, simply shortening the PS setting down to 4cm will accomplish the same thing but do it automatically.

By shortening that parameter you actually improve the response of the machine not reduce it. It works on the downward side just as well as the upward side, when events settle down EPAP will drop, as it drops and reaches the end of that max PS setting it begins pulling down IPAP pressure. If that setting is at 8, it EPAP then has to drop much farther down before it will begin pulling down IPAP with it. If PS=4cm is still a huge amount of exhale relief but it can begin pulling IPAP down much sooner. You probably won't notice the difference.

Now if your PSG showed only Hypopnea and zero apnea, then the above probably would not apply. If that was the case you probably don't snore at all either.

I would simply lower the PS=4, if you are already there, then I would increase EPAP by 1cm.

[rested gal]

Mike, if it were me (I'm not a doctor or anything in the health care field) I'd try these settings with your BiPAP Auto:

AbFLE (mode)
9 min EPAP
20 max IPAP
8 max PS
3 Flex
0:00 Ramp
0:00 Start
0 Patient
1 Light
___ Nights (leave that number as it is.)

[Snoredog]

Mike, if it were me (I'm not a doctor or anything in the health care field) I'd try these settings with your BiPAP Auto:

AbFLE (mode)
9 min EPAP
20 max IPAP
8 max PS
3 Flex
0:00 Ramp
0:00 Start
0 Patient
1 Light
___ Nights (leave that number as it is.)

Psssssssssst RG, I bet it wouldn't have worked if you also didn't raise IPAP max, by raising that alone, you allow EPAP to run up higher But how do you know which parameter worked?

are you assuming he is still at 7cm EPAP when those REM apnea take place? or are you assuming his IPAP is at the 16cm ceiling? Or both?

That was my guess if PS=8, that could easily happen if no OA's were seen until he reached REM. If only Hypopnea was seen IPAP could be near the 16cm ceiling and EPAP sitting on the bottom, then once he hit REM the apena started kicking in, too late for EPAP to increase to eliminate them.

A shorter PS shoulda/woulda accomplish the same thing without increasing pressure any. When IPAP bumps up to the 20cm Max ceiling, with a PS=8, he may still be at 12cm EPAP (20cm -8cm = 12cm).

With current pressure ranges remaining unchanged (i.e. 7-16cm) using a shorter PS setting, PS=4, if he would bump up against the IPAP 16cm setting, EPAP would have to be at 12cm (minimum) but at a much lower IPAP pressure being used (16cm vs 20cm).

Mike: try it both ways and let us know which works better will ya?

For you, one way means a lower starting pressure and how that relates to therapy comfort when you are falling asleep. If you are okay with higher pressure it may not mean anything.

The other way results in a higher starting pressure (9cm vs 7cm) and higher IPAP pressure ceiling, both basically accomplish the same thing which is allowing EPAP to run up higher to address the apena seen during REM (which is your main goal of this thread). Hypopnea seen (with the machine) don't generally wake you up, apena would. So the events that are waking you are most likely apnea, not hypopnea, since the unique pressure of that machine addresses these events differently, you work on the one that addresses the apnea or is causing the problem.

Hopefully you now better understand the concept(s) behind your machine and what rules that apply to setting it up and can make the change needed. Let us know.

[Wulfman]

Mike,

If you DON'T have the software and card reader to monitor your therapy.....it would be well worth the money.

Best wishes,

Den

[MS69]

Thank you for all the responses. The PS was set at 5, I moved it to 4 but there wasnt that much of a difference. What would happen with a higher IPAP? I generally wake up and hour or 2 after I fall asleep, go back to sleep, and then wake up again in progressively longer cycles. sleep--->2 hrs wakeup---> 4 hrs wakeup and so on. There may be more that I dont notice. The software is coming so I can post results without asking you to throw darts at the target in complete darkness. Thanks again.

Mike

[bdp522]

Glad to hear you're getting the software(and card reader too, I hope)! I'm sure you will find it to be an excellent investment. If you have any trouble with the installation, post back and someone will help.

Brenda

[rested gal]

snoredog and I agree on a few things, but not on how to handle the PS (Pressure Support) setting on the BiPAP Auto machine.

Unless a person has a particular medical reason to not allow IPAP and EPAP to range away from each other very far, I think it's best with the BiPAP Auto specifically, for most people to set the Maximum Pressure Support as high as it will let you. Depending on how far apart the EPAP and IPAP have already been set, "8" cm's is the most the PS (Max Press Sup on M machines) will allow for setting the maximum distance EPAP/IPAP can actually operate apart from each other.

I see no reason for most people to have the PS set closer. I see no reason for most people to have IPAP dragging EPAP up unnecessarily. When using the BiPAP Auto with auto-titrating turned on, I think it's better to let both those separate pressures "do their own thing" as much as possible.
viewtopic.php?t=15666
Dec 08, 2006 subject: Question for BiPap users - UPDATED 12/14/2006

I personally wouldn't want a tight leash (the PS) between EPAP and IPAP making EPAP be dragged up simply because the IPAP might have to range upward quite a bit at times during the night.

Turning to the regular EPAP/IPAP pressures for a moment...in my non-medical opinion, it's important to have the EPAP pressure set high enough to prevent apneas. Of the two pressures, EPAP is the most important pressure to "have right", imho. If you have the EPAP set right when using auto-titrating with the BiPAP Auto, the EPAP pressure is generally not going to have to go up much at all on most nights.

If a person has the cpap titration table from their night in the sleep lab, they can get a good idea where to set the EPAP. Set it at the pressure where they were in REM and no Obstructive Apneas were showing up. For most people, I'd bet that pressure is something like 7 or 8 or 9, even if the final titration pressure that was prescribed ended up being more...even quite a bit more. The "more" is what the IPAP pressure will take care of.

If a person does not have access to their cpap titration table from the sleep lab, then having the software is a must to be able to see what goes on with the settings you choose.

While the EPAP is the important pressure (again, in my opinion) it's also important to set the IPAP high enough to let the auto-titrating BiPAP Auto use what's needed to handle other events -- hypopneas, flow limitations, residual snores. If leaks are well under control (very low leak rate) it doesn't really matter how much "too high" you set the IPAP when using the BiPAP Auto with auto-titrating turned on, since the IPAP is not going to go up there unless needed. I'd set the maximum IPAP at 20.

As the others have mentioned, having the software to see what's going on is crucial if a person is going to try to work with his/her settings on any machine other than a straight cpap. I'd want to be using software even if there were a doctor in the loop, but especially if the person is going to handle their own settings completely alone.

All that said, of course there will be people who do better with certain settings, certain machines, and even straight cpap with no exhalation relief. Everyone's different, but if a person is going to use the BiPAP Auto and let it auto-titrate, I think a good starting place for most people (not "all", but "most) is:

Bi-level (M machines) or AbFLE (the older machine)
Min EPAP set at 7 or 8 or 9
Max IPAP set at 20 (assuming the leak rate is nice and low)
Max Press Sup (M machines) or Max PS (the older machine) set as high as it will let you. In the case of these EPAP/IPAP settings, "8" will be as high as it will let you.
Biflex turned on, set at 3

Results seen through the software would give you an idea of what, if anything, needs changing from settings like those to start with.