Remstar Auto - Runaway Machine or Runaway Body?

JL · Post by JL » Fri May 13, 2005 4:09 am

Strange...have been having reasonably good luck and consistency with pressures staying in the 8 - 11 range most of the time with a few minutes at 12 or 13. Last night felt like things ran away from me. Awoke due to high pressures I guess and was unable to sync up my breathing with the machine to go back to sleep. Just shut it down and got up. Downloaded data and was shocked to find that pressures had gradually kept climbing over the night from 8 on up to 18. The report does show OA/H events as pressures climbed but no more than I've had on previous nights without it going ever higher and higher in pressure. Definitely going to reset limits tonight from current 8-20 to something like 8-14.

Anyone have this experience? Ideas on what happened...machine runaway or body runaway?

Jim

wading thru the muck! · Post by **wading thru the muck!** » Fri May 13, 2005 4:31 am

Jim,

Same thing happened to me last night. I know I was "mouth breathing" last night and think this was the cause. The easiest thing to do is to just hit the ramp button. This will reset the machine back to the min pressure. Excesive snores can cause this to happen also. Let me know if you come to any conclusions.

JL · Post by JL » Fri May 13, 2005 4:57 am

Numbers for AHI a bit worse than usual at 8 and 9, snoring worse than usual at 10 but no snoring above 11 (wearing chinstrap). Numbers at higher pressures just don't seem to justify machine going over 13/14 tops.

Sleep study suggested pressure setting at 10. Will reset tonight for 8 - 14 and "start over"...at least then I won't have to worry about the RUNAWAY ROGUE CPAP MACHINE!!

Jim

Janelle · Post by **Janelle** » Fri May 13, 2005 7:13 am

This seems to be a problem on both the Remstar Auto and the PB 420E Auto. Usually resetting the 1FL to 0 will do the trick. You could limit the top pressure too, but resetting the 1 FL seems to take care of this problem on these two machines.

wading thru the muck! · Post by **wading thru the muck!** » Fri May 13, 2005 7:17 am

Janelle wrote:This seems to be a problem on both the Remstar Auto and the PB 420E Auto. Usually resetting the 1FL to 0 will do the trick. You could limit the top pressure too, but resetting the 1 FL seems to take care of this problem on these two machines.

There is no adjustment for this on the REMstar machine. Only the PB420E has this option.

neversleeps · Post by **neversleeps** » Fri May 13, 2005 9:34 am

Okay, so what are we supposed to do about it????

I have the REMstar Auto and have the same problem with runaway pressure. So aside from setting it on CPAP at a set pressure, is there any solution for runaway pressure? If I use it on the APAP setting at 10/14, it goes up to 14 and stays there. If I use it at 10/17, it goes up to 17 and stays there.

I did a self-titrating experiment over the course of a couple weeks (thanks RG, for your guidance!) and it seems I have the least amount of occurrences at 11 or 12. It frustrates me that the REMstar Auto doesn't function as it's supposed to when its set at a low/high range. It just streams up to the highest pressure and stays there.

I understand it has to do with the algorithms used by REMstar, but this means I can only use it in the CPAP mode to avoid runaway. I can't use it in APAP mode for the purpose it was intended: to adjust for sleep position, illness, weight, or any other variables as I had hoped when I purchased it.

So apparently the 420E has this thing you can turn off so it won't runaway and it will adjust for the afore mentioned variables in APAP mode, right? Well, I wish I'd known this before I bought my REMstar! Why would anyone buy a REMstar if they knew this in advance?

The question is, should I sell my REMstar and buy a 420E instead? But the 420E doesn't have a cflex-type function, does it?

I'm at a loss for what to do next... Any opinions???

wading thru the muck! · Post by **wading thru the muck!** » Fri May 13, 2005 9:47 am

Neversleeps,

The PB420E does have several options for making adjustments but it is in no way fool proof. You may experience this pressure run-up with the PB also. You mention rested gal. I know she required this adjustment when using the PB, but also uses the REMstar auto as-is with no problems. The algorithms are designed to work within a range of common breathing patterns. Some people are outside of this range and do not do well with an auto-pap. My guess is that it is recognizing your normal breathing pattern as an obstructive one and is attempting to set a pressure level that eliminates the obstruction. Do you have a nasal obstruction of some kind? As a consolation, you may find that using a fixed pressure on the REMstar along with the C-flex may provide more comfort than PB420E responding correctly but without C-flex.

derek · Post by **derek** » Fri May 13, 2005 10:07 am

How appropriate! I just posted a new thread
CPAP is better than APAP
that I think explains how this runaway might occur. I have noticed it also. It all has to do with your pressure-AHI curve and can generate a positive feedback contition if you have a definite minimum in your curve...

Anyway, that's my theory and I'm sticking to it...

derek

neversleeps · Post by **neversleeps** » Fri May 13, 2005 10:54 am

Thanks for the info, wader!!

No, I don't have a nasal obstruction; had the surgery and everything. I do know that my airway is easy to close just by imitating a snore as I sit here. Also, when they put in the breathing tube during my surgery, they had a very difficult time getting it in.... claimed I was anatomically 'different'. I wish someone would invent a permanent breathing tube to surgically replace my own. No more CPAP, no more snoring!!

wading thru the muck! · Post by **wading thru the muck!** » Fri May 13, 2005 11:03 am

My guess is your anatomical "difference" is what is fooling the apap (if that is what is causing the presure run-up). The nature of your airway obstruction may be other than what is recognized the the apap algorithm. I know you may be disappointed if the auto feature does not work for you, but that is the beauty of today's apaps. They can be switched to fixed pressure mode if that suits you better. You might consider a trial using a very narrow range to see if bring up the bottom can minimize the run-ups.

neversleeps · Post by **neversleeps** » Fri May 13, 2005 11:11 am

That's a good idea. I'll try the narrow range experiment and see what happens. I will, however, always wonder if the 420E in its auto setting would have worked for me with my apparent anomaly...

WillSucceed · Post by **WillSucceed** » Fri May 13, 2005 11:59 am

neversleeps wrote:

So apparently the 420E has this thing you can turn off so it won't runaway and it will adjust for the afore mentioned variables in APAP mode, right? Well, I wish I'd known this before I bought my REMstar! Why would anyone buy a REMstar if they knew this in advance?

Neversleeps: I'm sorry that this has happened to you. Any chance of returning your machine for a different one or, raising a stink with Respironics to get them to help you out somehow?

Forum members/posters:
For months now I have been reading the virtues of RemStar Auto with C-Flex as though it is the answer to everyones prayers. Clearly, it is not. I've also encouraged (in MANY posts) those who are getting ready to purchase a flow generator to trial ALL of the auto machines, for several weeks each, BEFORE they make their selection, so that they can get the machine that fits their individual needs the best.

I think we do a disservice to new users of this forum when we rave about any one machine (I've seen many, many statements like: 'get the Remstar Auto with C-Flex') rather than talking about the features of all the machines. People new to OSA are likely to be feeling very frightened and vulnerable (I know I was) and need lots of helpful information moreso than they need individual opinion.

I realize that it is human nature (actually, the dynamic is cognitive dissonance) to want to talk positively about the value of the thing that we have invested in and, see it's perceived value increase when others also invest, but, in this example, the reality is that the RemStar Auto algorithm is not good for everyone. Further, having C-Flex does make the RemStar units 'better' machines; if the auto function of the RemStar machine is not working well for an individual, the C-Flex function isn't worth jack squat as compenstation.

So, for those of us who have some experience with treatment, we should talk about our good experience with any particular machine, but do so with the clear statement that this was our individual experience only and that anyone looking to purchase a new machine should really try to trial ALL of the machines. Let's try to help others avoid the problem that 'neversleeps' now has.

neversleeps · Post by **neversleeps** » Fri May 13, 2005 2:18 pm

WillSucceeed-

Well, I'm just as guilty of cognitive dissonance as the next person...

I doubt Respironics would do anything about my poor REMstar Auto experience. Buyer beware and all... I'm not doing this through insurance so I can't return it for a different machine. I am toying with the idea of buying the 420E. I could see if it works for me in the Auto mode and if so, try selling my REMstar. So many people love the REMstar and the algorithms are right for them, I should think it would be easy to sell.

Then again, I read Derek's post:

viewtopic.php?t=2831

and I wonder if APAP is all it's cracked up to be.

What to do, what to do....

You are right about people espousing their choice in machine and/or mask. In terms of mask selection, I think there should be a permanent post explaining comfort and fit are highly subjective based upon the shape of one's head, the shape of one's face, the shape of one's nose, the amount of fat on one's face, the prominence of one's cheekbones, the distance between one's eyes, etc. There are so many factors influencing proper fit and comfort, one cannot possibly make a selection based on someone elses proclivities.

This really is a never ending process, isn't it?

rested gal · Post by **rested gal** » Fri May 13, 2005 2:50 pm

Neversleeps, while waiting until you can try a 420E, you could do this:

Set your Remstar auto to a range of the low you prefer and a top of 11 or 12.

That would be no "worse" (pressure-wise) than setting it for straight cpap at 11 or 12.

With it on auto reined in at a top of 11 or 12, you might still get to spend some of the night at lower pressures. And you'd still get to see data. Bearing in mind, of course, that the data would be what the machine is sensing (right or wrong) about your particular airflow characteristics....not necessarily what's really happening.

Having seen your data from the Remstar, I do think the excessive amount of snores that are showing up are the culprit. Is there any way you could audio record yourself one night to find out if you really are snoring that much?

wading thru the muck! · Post by **wading thru the muck!** » Fri May 13, 2005 3:09 pm

Willsucceed,

I think YOU do a disservice to particular forum members when you put words in their mouths. I don't recall ANYONE ever posting that the REMstar auto is "the answer to anyones prayers" You have attempted to misrepresent the information presented by supporters of the REMstar auto. I personally wrote a very detailed review of all the features and drawbacks of this machine. There is no way to know if an individual is incompatible with a particular auto unit unless they try it. In the large scheme of things these machines are incompatible with very few people. A far as the C-flex it is completely independent of the auto feature. The auto feature does not even have to be on to use the C-flex. Have you used this machine? I have used this machine and the PB420E and though both work fine for me I much prefer the auto w/ C-flex. By making that statement am I misleading the "frightened and vulnerable?" I can't see how I am.

Remstar Auto - Runaway Machine or Runaway Body?

Remstar Auto - Runaway Machine or Runaway Body?

Runaway pressures