Inhalation stops abruptly; please help a new bi-level user.

[hal]

I've been using a cpap machine (a Resmed S7) with Mirage Swift nasal pillows for over 2 years. It's worked pretty well, but my doctor feels that I would benefit even more from a bi-level machine.

So a few days ago I started using one (a Resmed VPAP III), and I'm having a terrible problem. After a few seconds of inhaling, the machine stops the inhalation abruptly, and I feel for a moment that I can't breathe. Before I’ve finished taking the full breath in, it’s as if the machine is telling me that I’ve had enough.

My settings (prescribed by the doctor) are 11 inhalation and 7 exhalation. As far as I know, all the other settings are the defaults.

Before I call my DME and my doctor, I turn to all the knowledgeable people on this forum. (I've read some of your posts, and am greatly impressed by the information and suggestions in many of them.)

Why is the inhalation ending abruptly before I've taken a full breath? Could there be some way in which this is normal? Is the machine defective in some way? Do some settings have to be changed? (I have the Technician's Manual, and I understand that any tweaks should be done very carefully.) What can I do?

The past few nights have been the worst of my life. Any help you can give will be very much appreciated. Thank you.

[oceanpearl]

If it is a flex system I would try changing the flex settings. That worked for me.

[hal]

If it is a flex system I would try changing the flex settings. That worked for me.

I'm new to this. How do I know if the VPAP III is a "flex system"?

[rested gal]

I used a resmed VPAP III for a few weeks, just for the heck of trying it out.

I had the same thing happen you did, hal... inhale breath abruptly cut off long before I'd finished inhaling. It doesn't actually stop the flow of air, but it sure feels like it when it switches suddenly to the lower EPAP pressure before you've taken in a normal full breath.

The IPAP Max setting is what's probably cutting the IPAP off too soon for you.

Here's what I did to mine:

I went into the clinical menu.

I left my IPAP/EPAP where they were (I had already set IPAP 12 / EPAP 9 ... the way I wanted it. )

I adjusted three other settings to these numbers:

Rise Time 900 mS
IPAP Max 4.00 s
IPAP Min 0.10 s

Went more smoothly for me like that.

Personally, I find using bi-flex in a bi-level machine more comfortable that adjusting a rise time. If you ever get a chance to try out the Respironics BiPAP Auto with Bi-flex (or even any Respironics BiPAP with Bi-flex) you might like that even more.

Or not. Everyone's different. The Respironics bi-levels give you a choice of setting a rise time or using bi-flex. Very versatile.

Good luck.

How do I know if the VPAP III is a "flex system"?

It's not. "Bi-Flex" is Respironics' trademark name for a comfort feature that softens the transition between inhale and exhale. The main thing I liked about using Bi-flex is that it makes the beginning of the already lower EPAP pressure be even a tad lower. Like icing on the cake. Very easy to exhale.

[oceanpearl]

Isn't the flex on that one called TiControl??

[hal]

I used a resmed VPAP III for a few weeks, just for the heck of trying it out...

I left my IPAP/EPAP where they were (I had already set IPAP 12 / EPAP 9 ... the way I wanted it. )

I adjusted three other settings to these numbers:

Rise Time 900 mS
IPAP Max 4.00 s
IPAP Min 0.10 s

Many thanks for the information, rested gal, but I don't understand. If your IPAP is 12, what does it mean to set your IPAP Max to 4.00? And why also change the other 2 settings?

[christinequilts]

How ironic when this is exactly what I just suggested to BrianRT in his thread about what do want to see covered in handouts for patients.

There are two things that can be going on- one is the machine may need to have what I term 'comfort settings', versus regular prescription settings that are determined by titration. The other thing can be user-machine interface issues- that's a polite way to say sometimes people don't interface with BiPAPs very well in the beginning I'm not sure how you know about how BiPAPs work, but the machine is not in charge, you are. When you inhale, it gives you the higher IPAP pressure, and when you exhale, it gives you the lower EPAP pressure. If you do nothing, it stays at the lower EPAP pressure. The machine has to try to predict somewhat when you're going to switch from inhale to exhale and back, so what can happen is that at the end of your inhale, you don't realize its getting weaker and the switch over to EPAP kind of slaps you in the face. Which throws you into a panicky mode. Try taking a few deep breaths in through your nose and out through your mouth- assuming you're using a nasal mask. I don't know why this helps, but I remember nearly 4 years ago when I started with BiPAP that it helped if it didn't feel in synch with me. If you start trying to follow the machines lead, you soon start to feel like a dog chasing its own tail. You're the one who is leading the machine, not the other way around.

If you work through that and its still happening, then you'll have to consider if the 'comfort settings' may be incorrect, but don't start playing with them until you're sure its the machine, not you...and you write down all the setting before you change any of them. Thankfully RestedGal recalled the exact terms the VPAP III uses & she gave you very good setting ranges, though I would tend to set the Rise towards the middle of the road, around 500ms, and only go up to 900ms if you need it. If rise time is set too low/too fast, then the switch from IPAP to EPAP feels jerky, startling, or even like a slap in the face feeling. My best friend tried to get me to 'hear' the slap or boom over the phone when she was switched to BiPAP a couple years ago. We had a good laugh once I realized what she was experiencing and we got her machine set correctly.

Let us know how it works out. Occasionally some of us just don't get along with a certain machine- me & VPAP II STA & VPAP III STA never could get in synch, so I ended up on a Respironics Synchrony until I switched to the new VPAP Adapt SV 6 months ago, which is a whole another animal.

[betty303]

I am still unclear what the rise time does, and how to set it. (Isn't it limited by the gap between your Ipap and Epap?

I use a Respironics M-series Auto Bi-Pap, with 11/7pressure settings and BiFlex on 3.

It is confusing to me what Bi-Flex is doing and what rise time does.

[christinequilts]

Not RG, but I'll jump back in...


Rise Time 900 mS = time spent transitioning between IPAP to EPAP, 100mS would really fast, sudden & jerky; 900mS would the the slowest (IMHO- start at 500mS and go up from there)

IPAP Max 4.00 s = the maximum amount of time that it can spend at IPAP, in all honesty, you're never going to inhale for more then 4 second (most people breath 12-16 times per minute, at 12 times per minute, you would inhale & exhale in 5 seconds)

IPAP Min 0.10 s = the minimum amount of time spend in IPAP. For people with OSA, setting it at 0.10 s is the best bet. Both IPAP Max & Min are used more for other, none sleep related breathing disorders.

Check your clinical manual, there should be charts that recommend Rise Times, IPAP Min/Max times for various uses- you want standard, run of the mill OSA.

[christinequilts]

I am still unclear what the rise time does, and how to set it. (Isn't it limited by the gap between your Ipap and Epap?

I use a Respironics M-series Auto Bi-Pap, with 11/7pressure settings and BiFlex on 3.

It is confusing to me what Bi-Flex is doing and what rise time does.

Rise time is how quickly it switches from IPAP to EPAP, but with Respironics BiFlex, you not only get the rounding or smoothing from IPAP to EPAP, but it also dips below your EPAP setting momentarily to make it an even smoother transition. Clear as mud?

Check out this graphic from Respironics:

See how the wave is really square with BiFlex off? Rise Time would round the corners, but you can see how BiFlex actually goes beyond that, and dips below for just a hair to make it easier to transition. I've never used a machine with BiFlex, only Rise Time, so I don't know how much it really adds personally. I do know if I set my Rise Time to the lowest setting on my Synchrony, it wasn't a pleasant experience. But more is not always better either, some people do best with BiFlex of 1 or 2, other need 3- so its a good idea to play around with it and see what works best for you.

[hal]

...Try taking a few deep breaths in through your nose and out through your mouth- assuming you're using a nasal mask.

I'll certainly try what you're suggesting, but -- since I'm using nasal pillows, not a mask -- do you think it would work the same way? Thanks.

[christinequilts]

Yep- it just doesn't work as well if someone is using a full face mask. And its only a few breaths to get yourself settle in, never more then 10 in row. It might also help to try to play with how the breathing feels a while before you go to bed, I know you've been on CPAP, but BiPAP is different enough that there is going to be a transition period.

Check the Rise time & IPAP max time too, but if your machine was brand new, I think the off the shelf settings are usually okay on VPAP III.

[hal]

Many thanks to christinequilts, rested gal and anyone else who may still contibute to this post. I'll try your suggestions over the next couple of days and report back.

[dsm]

Hal,

I have Vpap III S & S/T & have used them over approx 12 months in various trials & data gathering exercises. I am confident I can guide you through the use of yours (& can double check on the ones I have).

Forget BiFlex - that has nothing to do with your Vpap III (& serves as a bit of a warning as to the levels of expertise being offered to you on an open forum). BiFlex is on Respironics Bipap machines.

If your ipap cycle is ending abruptly 1st question I would ask is do you have an S/T model or an S model, this makes quite a difference in this area. The model type is on the front top of the machine.

Also, are you a COPD patient ? - (are you on BiLevel because of respiratory complications ? ) i f so I will be super cautious about any changes I suggest. Changing some values can be best done by an RT.

Do you know how to access the current settings & can you list them (if not we can guide you thru that).

Over to you & good luck

PS my own use of Vpap III was ipap=13 & epap=10

DSM

#2 Another critical bit of info in regard to what you are experiencing - what mask to you use & what mask have you set on the Vpap III's menu ?

#3 Created this thread after following one of Christine's references (tks CQ)
viewtopic/t20910/BiLevel-machines--how- ... -much.html

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CPAPopedia Keywords Contained In This Post (Click For Definition): respironics, bipap

[hal]

I apologize for not posting an update here much sooner.

Because of the helpful replies that were posted here, I did raise my Rise Time from the default of 300 to 900, and I also raised my IPAP Max from the default of 2.0 to 4.0. That solved my initial problem, and I no longer feel my inhalations cutting off abruptly. Thank you!

However, because of various other problems (some of them unrelated to cpap), I haven't used the machine at all for the past couple of weeks.

When I resume, I'll begin a new thread here -- and it'll certainly begin with asking how to deal with the noise that the VPAP makes.

In the meantime, though, thank you again.