Auto vs. Constant CPAP- I am confused

[beneyw]

After a month using tape to control mouth breathing I thought I was getting better 'subjective' results. I admit my ignorance in changing any machine settings but I know the DME set the range on my AUTO between 4 and 12 cm. I am now doing another titration study since the first, with a lot of mouth breathing had a high AHI and snore index.

Last night, everything was constant, the taping, my sleeping position, etc. and after about 3 hours I awoke, noticed the pressure was 9 and I was having some difficulty exhaling or so it seemed. I ramped the setting back to 4.0 and tried to go to sleep again. After about 30 minutes or so, and assuming I had not fallen asleep during that time, I checked the machine again and noted the pressure had risen to 10.0 and felt like a blowfish and/or my lungs were about to burst. At this point I became agitated and well, sleep for this night was about over.

It raises several questions:

Why did the machine not re-adjust to my needs and yet remain at a pressure of 10.0 cm. when I was not asleep? Is that how the AUTO works, once it reaches the maximum pressure I need shouldn't it automatically re-adjust downward during a wakeful period of time?

Could there have been leaking I was not aware of to cause the highest pressure yet recorded after 2 months of machine use or are there other things I should be considering? I know one thing, the 10.0 cm. of pressure was too much for me to nasal exhale.

I guess my understanding of how the AUTO CPAP works may not be correct and I am confused unless some of you great people have some possible explanations. Thanks.

[NightHawkeye]

Why did the machine not re-adjust to my needs and yet remain at a pressure of 10.0 cm. when I was not asleep? Is that how the AUTO works, once it reaches the maximum pressure I need shouldn't it automatically re-adjust downward during a wakeful period of time?

Beneyw, I'll answer your question, but first I'll explain the likely sequence of events for this thread:
1) question involving Respironics algorithm is stated (i.e., your question)
2) a possible explanation is offered
3) numerous statements are made that Respironics algorithm is so close to perfect no one could notice any adverse effects
4) thread degenerates quickly into tangential issues, emotional harangues, and vicious personal attacks as vested interests attempt to diffuse any direct discussion of the issue

(Please understand that this discussion forum is open to all and that some posters here are seriously vested in white-washing certain topics.)

Could there have been leaking I was not aware of to cause the highest pressure yet recorded after 2 months of machine use or are there other things I should be considering? I know one thing, the 10.0 cm. of pressure was too much for me to nasal exhale.

Yes, and as a practical matter, I think you would be well advised to monitor your therapy and try to understand what happens to cause the pressure increases. What I observed WHEN I USED A REMSTAR-AUTO was that 1) nasal congestion caused uncontrolled pressure increases, and 2) leaks caused uncontrolled pressure increases.

Are other machines any better? Beats me. I've never used anything other than Respironics. What worked for me was nightly nasal irrigations and careful control of leaks. As near as I can tell, taking these actions works for others as well. Again, I'll say that monitoring therapy with software is likely to help you understand and deal with this. Also, you should probably also consider alternative machines, however painfully expensive that prospect might seem. The major manufacturers APAP algorithms are significantly different from each other so that even if one causes problems for you, the others might not.

Hope this helps.

Regards,
Bill (just telling it like it is)

[Selena (but really Julie)]

NH - What? Beney wrote in with a legitimate question re setting his new machine, but your response was just incredible. Instead of help, you reamed him out about a whole load of stuff that was not in his note to begin with, and then did not answer his Q's at all!
To Beney - The diff. between CPAP and Auto is that while both have a 'theoretically available' range of 4-20, your MD or sleep techs start you out with a suggested setting of whatever.. e.g. 6 for the low setting (which means your machine starts you off at 6, though if it's initially too strong for you to fall asleep at, you can use the ramp to START at 4, and then it gradually comes up to 6 within 20 mins. THEN when you're asleep, if you have a CPAP, it will remain at 6 regardless of anything, but if you have an Auto, it may well jump to 8 or 11 or 15 if it detects a need based on how many apneas you actually experience. It may also go back down to whatever number periodically if things improve, and back up again if necessary. But if you're finding that you have trouble exhaling at pressures it rises to (in response to # of apnea events), possibly you need an Auto WITH C-FLEX (Respironics) machine that not only detects a need for higher pressures overnight, but can adjust itself at the same time to make exhalations easier, even if the pressure rises. So look into that machine with your MD or DME, etc.

[GoofyUT]

Beneyw-
You asked great questions. Don't fret.

Now answers:

1) I don't use a Respironics machine. I use a ResMed S8 Autoset VAntage. Itoo, have noticed it increasing presssure while I was awake. What seems to be happening is that the machine is interpreting variations in your wakeful breathing flow as being SDB (sleep disordered breathing) events and is mistakenly adjusting pressures to attempt to treat them. Now, with the ResMed, it has a feature that allows you to turn off the "brains" of the machine to allow you time to fall back asleep. This "SETTLING" time forces the machine to ignore events and not score them, and also not to treat them for a defined period of time (in my case, 30 minutes) while I fall back asleep.After that time passes, it goes back to doing its job of examining my flow rate and shape and detecting events which it them treats.

Now, Respirornics APAPs don't have a SETTLING feature as best as I know. They do have a ramp feature in APAP. HOWEVER, as I understand it, invoking the ramp (and having the ramp time set to anything other than "0" in Auto modes will cause the Respironics Auto to think it is doing a "split-night" titration study, and it will STAY at its MINIMUM pressure for quite a long time (hours). Given this, I'm curious as to how your machine went from 4 to 10 in a half hour when you "ramped" it back to 4. Can you tell us just how you actually ramped it back?

2) Your pressures are low enough that you generally wouldn't be a candidate for bi-level PAP. So, if you're having troubles with exhaling, you might want to consider adjusting your C-Flex setting. ResMed machines have NO expiratory relief in AUTO mode, and Puritan-Bennett have NO expiratory relief.

3) As Nighthawk pointed out, there have been reported instances of Respironics machines experiencing "runaway" pressures. I don't know much about this though.

Hope this helps.

Chuck

[Snoozin' Bluezzz]

...but first I'll explain the likely (future)sequence of events for this thread:
1) question involving Respironics algorithm is stated (i.e., your question)
2) a possible explanation is offered
3) numerous statements are made that Respironics algorithm is so close to perfect no one could notice any adverse effects
4) thread degenerates quickly into tangential issues, emotional harangues, and vicious personal attacks as vested interests attempt to diffuse any direct discussion of the issue

(Please understand that this discussion forum is open to all and that some posters here are seriously vested in white-washing certain topics.)

Bill, I'm normally with you but in this case I'm with
Selena, I don't think your aside was helpful to Beneyw, or anyone else, and obscured the real positive help you offered, and which was useful to me as well since I am struggling with a bout of congestion and haven't gone to the requisite lengths because it can be a pain in the patootie.

Perhaps you didn't have a good night last night?

We don't know where this thread will go and I even given my sense of how this forum can go at times I would not have predicted what you did given this comment.

I have noticed my numbers being distorted by late morning congestion and some congestion battles all night but not quite reflected in the APAP's behavior like Beneyw's.

Beneyw - your equipment show the current Remstar Auto with C-Flex rather than the older model without? Is this correct? I had the older Auto (without C-Flex) and it would do the same thing if ramp and ramp time were not set to zero when it was run as an auto.

David

[oldgearhead]

WOOAH! Two things:

1) Pressure 4 - x, too low for 'Min' pressure. What was your titrated pressure? Many agree 3 cm/H2O below and 2 cm/H2O above titrated pressure
gets the best results,
On the Remstar auto, the 'Ramp Time Setting' needs to be set at 0.0. Then what the ramp button does is to reset the machine to the 'Min' pressure. I suggest a higher 'Min' pressure.

2) Congestion - Taping your mouth and using a nasal interface will not solve a nasal congestion problem. You must find a way the limit the congestion, or try to adapt to a full-face mask..

I need at least 7 cm/H2O 'Min' pressure, to check for leaks, and assist my inhale function.

What's your C-Flex setting? How do you know 10 cm/H2O is not your 'correct' pressure?

[Snoozin' Bluezzz]

WOOAH! Two things:

1) Pressure 4 - x, too low for 'Min' pressure. What was your titrated pressure? Many agree 3 cm/H2O below and 2 cm/H2O above titrated pressure
gets the best results,
On the Remstar auto, the 'Ramp Time Setting' needs to be set at 0.0. Then what the ramp button does is to reset the machine to the 'Min' pressure. I suggest a higher 'Min' pressure.

2) Congestion - Taping your mouth and using a nasal interface will not solve a nasal congestion problem. You must find a way the limit the congestion, or try to adapt to a full-face mask..

I need at least 7 cm/H2O 'Min' pressure, to check for leaks, and assist my inhale function.

What's your C-Flex setting? How do you know 10 cm/H2O is not your 'correct' pressure?

IMO - Perfect answer to start with. The particulars may vary for you Beneyw but it works exactly the same way for me and 7cm is where I need to start.

I agree with the congestion comment too but you have not said whether it is a problem for you or not. It sounds like it might be based on your difficulty in exhaling against 10cm (which is not particularly high but folk's responses vary quite a bit). Have you spent much time at 10cm in the past? You may need to be at 10cm and going down to 4cm or even something significantly under 10 may not be helping your therapy much.

As an aside I seem to have variable responses to congestion. As summer builds up I have mild to moderate congestion in response to various allergens that builds to at least one very bad bout in the fall in response to Ragweed. This tails off through the winter to where I am pretty clear (on the xPAP) in late winter early spring (wish I could stay that way all the time). I have just been lucky to be quite clear for some time and am resistant to the congestion management regime I will have to undertake which is - irrigation, Flonase, and Astelin. I do not want to go to a FF interface, unless the Hybrid proves to be effective.

Hope this helps.

David

[beneyw]

The machine I am using is the Remstar Auto with C-Flex. My original titrated pressure was 8.5 cm. and I had a constant CPAP machine originally. I paid for the upgrade to the AUTO because I thought the word 'auto' meant auto adjusting as needed but the comments about being awake are interesting. The machine 'thought' while I was awake I needed more pressure perhaps and that only added to my heavier breathing therefore making an already bad situation worse. I thought I may have had some nasal congestion as well and with the mouth taped shut there was no way air could escape. By this time of course my mind is thinking all sorts of things each of which affect breathing and the resulting sleepness night.

I will be taking the smart card to a DME next week so we can see what the actual patterns show. One thing for certain, the tape sure as heck creates a closed system except for the nose.. slightly congested nose equals more pressure equals blowfish syndrome. Gosh, I knew it would take time and just when you think you got it nailed..bam, another fly in the ointment.

Ain't this fun??? Your comments are so well appreciated.

[Goofproof]

Oldgearhead, suggestions were right on. I suffer congestion 100% of the time and started out with a FF Mask, it is the most reliable method of treatment, not liked by many but the idea is to get the treatment working. I cuss the leaks at 6 am. I am sure the noises are being recorded as snores, and I toss & turn, but the first half of the night I sleep like the dead.

A Ff Mask, can be your friend, you just have to tame it, they are wildcritters.

Jim

[Bonnie]

Selena (but really Julie)
The ramp feature on the Remstar Auto Cpap cannot be used in auto, only straight cpap mode is my understanding.

_________________

CPAPopedia Keywords Contained In This Post (Click For Definition): auto cpap, CPAP, Ramp, auto

[Linda3032]

Bonnie, in the true sense of ramp, you are right the auto doesn't have it.

But, on my machine which is set from 6 to 8, if I hit ramp, the pressure reverts to my low pressure which is 6.

I haven't had to use ramp in some time, but with my nasalaire and pressures from 5 to 10, I used it quite often when I woke up with my pressure blowing at 10. It would immediately go down to 5 long enough for me to get back to sleep.

[GoofyUT]

But isn't it true Linda, that if you have the ramp time set to anything other than "0" in Auto, then when you hit the ramp buttton it'll go down to your lowest pressure and STAY THERE for a couple of hours?

Chuck

[beneyw]

When I hit ramp button now with the AUTO it goes back to 4.0 BUT not as long as with the constant CPAP. At least that has been my situation.

[Guest]

After a month using tape to control mouth breathing I thought I was getting better 'subjective' results. I admit my ignorance in changing any machine settings but I know the DME set the range on my AUTO between 4 and 12 cm. I am now doing another titration study since the first, with a lot of mouth breathing had a high AHI and snore index.

Last night, everything was constant, the taping, my sleeping position, etc. and after about 3 hours I awoke, noticed the pressure was 9 and I was having some difficulty exhaling or so it seemed. I ramped the setting back to 4.0 and tried to go to sleep again. After about 30 minutes or so, and assuming I had not fallen asleep during that time, I checked the machine again and noted the pressure had risen to 10.0 and felt like a blowfish and/or my lungs were about to burst. At this point I became agitated and well, sleep for this night was about over.

It raises several questions:

Why did the machine not re-adjust to my needs and yet remain at a pressure of 10.0 cm. when I was not asleep? Is that how the AUTO works, once it reaches the maximum pressure I need shouldn't it automatically re-adjust downward during a wakeful period of time?

Could there have been leaking I was not aware of to cause the highest pressure yet recorded after 2 months of machine use or are there other things I should be considering? I know one thing, the 10.0 cm. of pressure was too much for me to nasal exhale.

I guess my understanding of how the AUTO CPAP works may not be correct and I am confused unless some of you great people have some possible explanations. Thanks.

_________________

First thing you have to determine on your own is WHAT mode your machine is in. You can't trust them DME's they were flippin burgers last week. Just because you have an "Autopap" doesn't mean it is in the autopap mode. It could be in a straight cpap mode. Doctors like to play games like that when you ask for an autopap they give you one, but program it in the cpap mode so when you come back in a month and say I slept so much better they laugh to themselves and the DME takes back the autopap and gives you a straight cpap machine. I guess it makes them feel superior having the controlling hand over your therapy.

So unplug the machine, hold down them 2 left/right arrows while plugging the power cord back in, hold them down until 3 beeps are heard then release. Press right User button, first parameter will display the mode the machine is in. It if is in one of the autopap modes it will say either AFLE or AUTO. If it says CPAP or CFLE then it is in cpap mode, that will explain your problem. Use up/down arrow button to change values, use left/right arrow buttons to change to next field, On/Off button to save and exit programming.

There should be NO ramp function in autopap modes, that only works in cpap/cfle modes. Why does yours ramp? So if you are pushing the ramp down button and pressure decreases your machine is NOT set up correctly. If you wake up and see the pressure at 10cm, that doesn't really mean anything other than you needed 10cm to clear what ever events you were experiencing. The machine does not know if your awake or sleep, it only sees breathing patterns. If you wake up and start breathing normally, that 10cm should start to decrease gradually. If you were asleep and all events ceased it would take that machine about 10 minutes to drop back down to the LOWest pressure.

So I see your problem as having a machine not set up correctly to function in autopap mode, and having too low a starting pressure of only 4cm. It appears whomever set it up has no idea what they are doing.

So from your post I can tell, your titrated pressure is at minimum of 10cm (where the pressure was last seen at when you awoke). So if you want to fix it, go into the setup mode mentioned above on the machine and set it to:

AFLE mode (options are AUTO, AFLE, CFLE, CPAP)
Use CFLEX setting of 2 for starters (options are 1, 2, or 3).
Set LOW Ramp pressure to 6cm (default=4)
Set High Ramp pressure to 12cm.(default=20)
Set Ramp Timer value to 00:00 (default=00:00, must be zero as shown**).

**Set to zero 00:00 for AFLE/AUTO modes. If using CFLE, CPAP mode you could input a value between 00:05 to 00:45 minutes, then it becomes a standard Ramp timer but ONLY in CPAP/CFLE mode(s). Other possible modes available are 01:00 - 04:00 hours which are a special split-night modes, do not use these (your machine could be using this mode, again, person setting up machine had no idea what they are doing enabling this).

Now if your machine is set to the above, it will function like an autopap is supposed to. The above settings will NOT impact your titration study at all. Look in your manual for using the C-Flex feature, this will make breathing against the pressure much easier. The machine has to increase pressure when you are having OSA events. If you are a chronic snorer the machine will run at higher pressures to eliminate those snores.

[Selena (but really Julie)]

Hi - I use a Resp. Auto without C-flex, and I do have a ramp feature and I can use it whenever I want (though it's extremely rare that I do except to reset my pressure occasionally, which is another story entirely). Maybe newer (or older) machines don't have a useful ramp feature, or maybe the C-flex ones don't, but mine does and it does work.