Advice Needed-Aircurve Vauto or ASV

[William Dunn]

Hello everybody,

I have recently been diagnosed with OSA through a home study.  The doctor has prescribed BiPAP treatment to start with, in ranges of 12/7 to 25/20, with the goal of then dialing things in based on the results.  I had narrowed down my machine of choice to the Aircurve Vauto and was about to order... however, a wrinkle has just appeared.  I now have an opportunity to buy a used Aircurve ASV machine with around 350 hours on it for about $400 to $500 dollars.  I realize ASV and Vauto BiPap are slightly different animals, but I also suspect, based on my research and experience, that I am experiencing Central Events as well as OSA and anticipate I may very well end up with an ASV down the road.  I have seen others on these boards that finally got down to an ASV after multiple sleep studies and months or even years of trying to work things out before finally dialing things in on an ASV machine.  Considering the opportunity for this used machine, which I will be able to get for less than my insurance deductible anyway, I was wondering if I might just save myself the potential trouble and expense and jump on this opportunity while it is here.  If I can use the ASV machine in a way similar to the initial parameters set up by the doctor, I can then dial things in as I go, and if I end up needing the corrective for central events as well then I already have the machine to do it with and don't have to go through another song and dance later to try and get it.

I know this isn't exactly what I was prescribed by the doctor, but the doctor is going to be dialing things in by trial and error himself anyway.  My initial study was done at home, not in a lab, and I am supposed to consult with him again in two months, where he will no doubt just read the data and make adjustments.  I am not one to sit back and wait, however, when I can do the dialing in myself through experience and the help of the knowledgeable and experienced people on this forum - after all, I'm the one that needs sleep each night, not him!

So the question for you guys, who all have far more experience and knowledge than myself, is "is this plan feasible"?  Can I use this ASV machine in a way similar to an Aircurve Vauto?  What are the downsides, if any?  And what would you do in my place, knowing what you know now?

Thank you for your time and help.

[ajack]

Assuming you have normal heart and lung function. I think the common bpap can be substituted by the ASV. It's when other health problems present and a s-t-vaps type machine is needed. You will be better talking this out with your doctor, there is always another second hand machine out there.

[jerrydaw]

This is a hard choice.  If you suspect that you do indeed have centrals, then the ASV is about the only thing that will treat them.  I guess you know that the ASV machine will also function in a mode as a regular CPAP machine.  That will clearly handle your obstructives.  But i am not sure it will function in a true bilevel fashion. However, a regular CPAP machine does function in a limited (up to 3cm) bilevel  fashion via the exhale pressure relief option. I have my ASV set on a 3cm differential between inhale and exhale, and it seems OK.  With the ASV machine, you could start using the regular CPAP option, then shift if necessary to ASV.  

If it were me, I would jump on the ASV machine at this price and low hourly usage. That is practically a gift.

[dmeRT]

I'd get the ASV. you can adjust the settings to make it run as cpap, bipap, bipap s/t or asv

there must have been central events in your home sleep study to warrant starting with bipap. Save yourself the difficulties of acquiring an asv through insurance and pick up now.

[silversnore]

I think that the Aircurve ASV will do CPAP, ASV and ASV auto, not sure that it will do s, t or st. The ASV mode is going prod you to take mandatory breaths based on you normal breathing. There are a lot of of different parameters and i am not familiar with the programming to know if you can default the parameters. You should apply for the clinical manual from Super Sleeper to determine if the ASV will do what you need and want. Most of the time doctors want a cardiac work up for an ASV as there is some danger of using the machine if you have certain heart problems, especially in the the left ventricle.

[William Dunn]

Thank you for your opinions and advice everybody. Anybody else wanna chime in?

[ajack]

AFAIK The big difference is the asv works on the last 3-4 minutes average of ventilation volume. The asv will target 90% of this number. If this volume is insufficient, I don't think the ASV can increase to a preset target ventilation volume.
An ASV doesn't substitute for the more specialised units. It isn't for hypoventilation, nor do they all have trigger and rise adjustment.

I have recently bought a s9 adapt asv and am waiting on delivery. I'm not against them, but it must be kept in mind that they don't treat everything.

[DeepBreathing]

I think that the Aircurve ASV will do CPAP, ASV and ASV auto, not sure that it will do s, t or st

I believe this is correct. The modes available on the Resmed ASV are:

CPAP (fixed pressure only, no APAP)
ASV (with fixed EPAP)
ASV Auto (with auto EPAP)

There is no provision for setting the backup rate, rise, time in IPAP or trigger - these are all done automatically in ASV and ASV Auto mode, and not available in CPAP mode.

The doctor has prescribed BiPAP treatment to start with, in ranges of 12/7 to 25/20

Can you clarify this please? I take it to mean a variable EPAP between 7 and 20, with a variable IPAP between 12 and 25, with pressure support varying up to 13. Is that correct?  The Resmed ASV won't be able to emulate those settings exactly, but could come close if you use:

Min EPAP: 7
Max EPAP: 15
Min PS: 5
Max PS: 10

Note that the ASV has a max EPAP of 15. Also, it will adjust PS on a breath-by-breath basis, which is not the way the bilevel operates, but I don't think it would be troublesome.

Given the bargain deal you can get for the ASV, I'd give it a try. If it doesn't work out, you can always try to trade it in for a different machine.  The other thought that occurs to me is that the price might be too good to be true. Do you know and trust the vendor?

[ajack]

It's a bargain, only been dropped once 

[William Dunn]

Thank you for the info - yes, you are correct on the doctor's settings.  They were pretty vague but that's how I interpreted them as well.  I do not know the owner of the machine personally and this, of course, is also weighing on my decision.  However, I do know that he formally owned a sleep study business and supplier and this particular unit spent most of its life being used on a nursing home patient.  Owner is no longer in business and getting rid of some of his stuff.