Ramp on an APAP Machine

I don't understand what the purpose of the "ramp" is on an APAP machine. I understand that an APAP machine will automatically provide increased, adjusting pressure when apneas or hypopneas are detected, but when I first put on the mask and start the machine, I haven't yet fallen asleep and therefore don't have apneas/hypopneas that would require increased pressures. So what exactly does the ramp feature do on an APAP machine?

The ramp is a comfort feature to ease you into the pressure needed for treatment. Some people, especially neophyte users find it easier to go to sleep with lower pressures. Most of the people on this forum don't feel the need to bother and just go "full tilt boogie" right from the get-go. I include myself in the latter.

TASmart wrote:The ramp is a comfort feature to ease you into the pressure needed for treatment. Some people, especially neophyte users find it easier to go to sleep with lower pressures. Most of the people on this forum don't feel the need to bother and just go "full tilt boogie" right from the get-go. I include myself in the latter.

But if I'm awake when I turn on my APAP machine (before I fall asleep), I am not having apneas or hypopneas and therefore shouldn't be needing any increased pressures. What am I missing?

The ramps sole purpose is to help you ease into whatever pressure it is that you are supposed to start the night with.
That's it. Comfort only. Some people have to start out the night at much higher pressures than you...like me...I have to start with minimum of 10 when on apap so that the machine can get to 16 or 18 fast enough for my REM events. When I started it with a lower minimum I would have too many events clustered in what was likely REM.
Now I never really needed to use a ramp to help ease me into that 10 cm starting point but it was there if I ever needed.
Some people like starting low and slow and moving upwards in pressure that way. Some people just like the full pressure from the start.

Yes, Respironics machines will suspend ramp and go directly to work if it detects the warning signs of the airway closing...they have always done this when in auto mode but now they have the smart mode available for cpap mode also on the DreamStation models.
ResMed even has something similar in their auto ramp mode. They didn't used to do that.

So the sole purpose is comfort so that the person can false asleep and not stay awake fighting the machine until they get used to it.
If you don't want it or don't need it then it doesn't have to be used. Personal choice.
Just another tool to help avoid the machine's pressure maybe causing comfort problems because if we aren't comfortable it's hard to fall asleep.

Number one goal...fall asleep and try to stay asleep. Nothing much else matters if we can't sleep for whatever reason.

But if I'm awake when I turn on my APAP machine (before I fall asleep), I am not having apneas or hypopneas and therefore shouldn't be needing any increased pressures. What am I missing?

People still need to get to the minimum starting pressure for one thing and the other thing is that until recently none of the machines except Respironics in auto mode only would suspend ramp if it sensed something going on with the airway.
It's always best to try to prevent something from happening than it is to try to fix it after it happened. You do that by being at the minimum starting point and not at the minimum ramp starting point. Suspending ramp helps...but it is best to just hold the airway open better in the first place because suspending ramp still means the machine can take a couple of minutes to get to the needed pressure and sometimes the airway has closed and opened back up again while the machine is trying to get from say 4 cm to maybe 8 cm.

So what is happening with "ramp" if my ramp is set to start at 4cm H2O for 5 minutes, but my pressure range is 7 - 20cm H2O?

If you engage the ramp button when you first turn the machine on it will start out at 4 cm and in 5 minutes it will be at 7 cm whether you are awake or asleep.
It gradually will move up 3 cm in pressure during the ramp time and in your case it will take 5 minutes to do it.
If for some reason you fall asleep before the 5 minutes is up and it senses the airway trying to close up (snores or FLs most likely) it will suspend ramp and go directly to auto mode and do its thing. Once it no longer senses any airway closures if it has time it will go back to where it was in the ramp cycle but most likely with a short ramp of 5 minutes there won't be any ramp time left and the machine will stay at 7 cm until it needs to go to work again.

Pugsy - what's an FL? Is there a place where abbreviations are defined?

FL flow limitation

For the actual definition go here http://sleepyhead.sourceforge.net/wiki/ ... p/Glossary
Plus a lot more.

jweiner wrote: . . . But if I'm awake when I turn on my APAP machine (before I fall asleep), I am not having apneas or hypopneas and therefore shouldn't be needing any increased pressures. What am I missing?

If I may attempt to add my personal angle to Pugsy's excellent info:

There is wake. There is sleep. But in a sense, there is a third state, which is the transition from wake to sleep. We don't instantaneously flip a switch to get fully from one to the other instantly. In many respects, the first stage of sleep is a sort of combination of wake and sleep. It is as if the body were trying to switch gears and as it steps on the clutch, there is a brief pause in breathing that can easily lead to a narrowed airway BEFORE we are fully asleep, as it were. (Many of us were built four-on-the-floor, not automatic transmissions, apparently.)

For some of us, if any sort of narrowing of the airway starts to occur during the transition from wake to sleep, that will startle us immediately into full wake with a serious jolt that can keep us from falling asleep for a good while after that. For those of us with that issue, using ramp or having too low of a starting pressure is more detrimental than helpful to us, because we may start falling asleep before the ramp ends or before the pressure is high enough to keep the airway open.

The above is based more on my personal experience than on what I've read.

If you're not uncomfortable with the minimum pressure, there's no reason to use the ramp.

If you do find the minimum pressure too strong, then you should use the ramp.

Note that the "Smart Ramp" feature will accelerate the ramp if it thinks you need more pressure prior to the pre-set ramp-up time. This is available on the DreamStation APAP.

jweiner wrote:Pugsy - what's an FL? Is there a place where abbreviations are defined?

https://www.youtube.com/watch?v=-gie2dhqP2c

For anyone wondering about what I said about ResMed machines...remember we are talking apap/cpap models here...not talking about what ResMed bilevel machines may or may not do with ramp. I don't remember seeing it in my AirCurve 10 ST but then again I didn't look. If I have time later I will go look.

The new AirSense 10 machines have "Auto Ramp" which is supposed to be able to sense when someone is asleep and when we are asleep is when the airway will try to collapse (if it tries) so presumably the machine should be able to handle any airway collapses because it should already be at the prescribed pressure because it thought a person was asleep. I have no idea how accurate this feature is but I would think that there was extensive testing to prove their marketing hype.
page 10 of the manual and page 16 talk about it.
https://sleep.tnet.com/home/files/resme ... -guide.pdf
I can't tell if Auto ramp is available on the Elite or CPAP models. It appears to be an option from the manual though.
No S9 machine has AutoRamp....brand new to the AirSense and maybe the AirCurve.

This Auto ramp thing is brand new to the AirSense models (and maybe AirCurve but I haven't verified and don't have the time at the moment).
It's new and it's a back door way of addressing any airway collapses that might occur when a person has fallen asleep prior to ramp time being over. It is a special ramp setting though...the regular ramp does like ResMed has always done...you use up the ramp time first and then the machine is at the minimum pressure. If ramp is set for 45 minutes and you fall asleep after 15 minutes and the airway closes at 5 minutes after sleep onset then it is very possible that the pressure won't be up near to what it needs to be to deal with it. It all depends on what the ramp starting point is and what prescribed setting is. Not a big deal if it is taking 45 minutes to go 3 cm but could be a problem if it takes 45 minutes to go 12 cm.

Respironics has similar but calls it SmartRamp and it's available in all modes and they talk about addressing airway collapses instead of sleep onset but the end result is the same...we don't have an airway collapse that is sleep apnea unless we are asleep. That's why they call it sleep apnea.

Respironics has suspended ramp in auto mode on the apap machines since at least the M series machines...so that's nothing new and something that is built in and a person doesn't have to make a special selection...now they also offer it in other modes including bilevel machines (fixed or auto)...but it's now called SmartRamp.

So the old advice about "you don't get therapy when in ramp" isn't necessarily a statement that pertains to everyone anymore.
It depends on which machine, which mode and if using a newer model (DreamStation or AirSense) it will depend on if SmartRamp or AutoRamp is being used.

Now can the ResMed really distinguish sleep status?...beats the heck out of me. I haven't seen any documents discussing accuracy but I would think they have some to back up the hype. I just wonder why if they can tell if a person is asleep or not then how come we get sleep/wake/junk flags on the AirSense machines.

It seems that ResMed is calling it an "auto Ramp," but Respiornics is calling it a "Smart Ramp." It works like a standard ramp, except that it will ramp up sooner if it senses distress. Somebody said that it will ramp up if it senses sleep, but I don't think that it really can identify sleep.

Chiming in with my two cents based on what actually happens on my PR DreamStation BiPAP Auto when I use the Smart Ramp. I won't speculate on what happens with the Resmed AirSense/AirCurve machines and their AutoRamp.

First: Yes, I'm a wuss when it comes to pressure. For years I was able to use an EPAP range of 4-6 with good results, but for reasons that remain unknown to me and my sleep doc, this past spring it was clear my old settings (min EPAP = 4, max IPAP = 8, min PS =2, max PS =4) were no longer working to control the OSA as well as I needed. So we discussed experimenting with increasing the min EPAP pressure to 6 and the max IPAP to 10. But the old aerophagia problem returned. So in experimenting with what to do, I decided to turn on the Smart Ramp feature with a starting EPAP = 4.

My current pressure settings (which are working for me in terms of AHI and are tolerable wrt aerophagia) are:
min EPAP = 5.5
max IPAP = 10
min PS =4
max PS = 4.5

My ramp settings are: SmartRamp = ON; Starting EPAP = 4; and ramp time = 30 minutes. So when I hit the ramp button, the pressures are immediately reduced to 8/4 (which is comfortable for me and does not induce aerophagia).

But because the SmartRamp = On, the machine does NOT immediately start gradually ramping up the pressure. Rather a modified version of the standard PR Auto algorithm is in place meaning this:

1) If the machine scores anything that warrants a pressure increase, it increases the EPAP (and IPAP) pressure under the standard auto algorithm and will NOT reduce the EPAP pressure below the new EPAP pressure setting as long as that new EPAP pressure setting is less than (or equal to) the min EPAP.

2) If the breathing is stable enough for the danged "PR Search Algorithm" to kick in during my longish ramp period, a modified version of the PR Search Algorithm kicks in. On a PR BiPAP Auto, the Search Algorithm is usually only increases the IPAP, but during the Smart Ramp period, the Search Algorithm increases both my EPAP and IPAP. And if the breathing is not improved with the 1cm test increase, the pressure is lowered back down. If the breathing improves, the search algorithm continues with the new higher pressure as the "minimum pressure" until the end of the ramp period is reached.

3) If the EPAP pressure reaches the minimum EPAP setting (of 5.5 cm in my case) during the Ramp Period, the pressure is never allowed to go below the min EPAP pressure. In other words, the Ramp effectively ends once events or the Search algorithm cause the pressure to be increased to the minimum pressure setting.

4) If the EPAP pressure is still below the minimum EPAP pressure at the end of the ramp period, the pressure is then increased linearly over a short period of time until the minimum pressure setting is reached.

My understanding is that the Smart Ramp on all PR Dreamstations works in a somewhat similar fashion. This is quite different than how old PR System One BiPAP Auto's regular ramp worked. On the System One, the ramp was a linear ramp that started increasing the pressure right away; with the Smart Ramp the pressure stays at the beginning ramp pressure until an event occurs or the Search algorithm kicks in.

I'll end my reiterating: Yes, I know I'm a wuss when it comes to pressure: When I am trying to get to sleep at the beginning of the night, the stomach does not want to deal with an EPAP of more than 4cm. And when I wake up in the middle of the night, my first thought is "Make the Stomach Comfortable" so that I won't have additional trouble getting back to sleep. For me, the big difference between using the Smart Ramp and my old setting of Min EPAP = 4 is that except for the ramp period, the EPAP pressure is never lower than 5.5. When I was using Min EPAP = 4, my EPAP pressure was often below 5.

This is exactly my situation; can't use ramp because of sleep onset centrals and /or
Airway collapse as I fall asleep.

Great description. Too many of those jolts in a row and I'm unable to get back to sleep
For hours.

jnk... wrote:

jweiner wrote: . . . But if I'm awake when I turn on my APAP machine (before I fall asleep), I am not having apneas or hypopneas and therefore shouldn't be needing any increased pressures. What am I missing?

If I may attempt to add my personal angle to Pugsy's excellent info:

There is wake. There is sleep. But in a sense, there is a third state, which is the transition from wake to sleep. We don't instantaneously flip a switch to get fully from one to the other instantly. In many respects, the first stage of sleep is a sort of combination of wake and sleep. It is as if the body were trying to switch gears and as it steps on the clutch, there is a brief pause in breathing that can easily lead to a narrowed airway BEFORE we are fully asleep, as it were. (Many of us were built four-on-the-floor, not automatic transmissions, apparently.)

For some of us, if any sort of narrowing of the airway starts to occur during the transition from wake to sleep, that will startle us immediately into full wake with a serious jolt that can keep us from falling asleep for a good while after that. For those of us with that issue, using ramp or having too low of a starting pressure is more detrimental than helpful to us, because we may start falling asleep before the ramp ends or before the pressure is high enough to keep the airway open.

The above is based more on my personal experience than on what I've read.