goodonya,
The Resprionics ASV machine has a backup rate feature. It can be set to OFF, AUTO, or a specific number of "breaths per minute" when the machine is run in ASV mode.
If your prescription did not include a back up rate or specified that the back up rate be turned off, then chances are that the DME set the machine up with the back up rate turned OFF because they were following the prescribing doc's orders.
And if you buy a brand new Resmed S9 Vpap Adapt (the Resmed ASV), and have the DME use the same prescription to set up the S9, then chances are the DME will turn the backup rate OFF on that machine as well.
In other words, the first thing you need to do is find out
why the prescription has no back up rate. It could be that the sleep doc's office intended for the back up rate to be set to "Auto" instead of "Off", but the DME misinterpreted the script.
In other words, the first step may be to get your current machine set up with better settings rather than spending $3000 or more for the S9 VPAP Adapt. If I were you, I'd call the sleep doc's office and ask them to change the script so that the Backup Rate is set to AUTO rather than OFF. (If you're comfortable with changing your own settings, you could do this yourself through the clinical menu.)
(01-09-2014, 06:05 AM)goodonya Wrote: I was reading the fine print on my Respironics ASV Bipap and saw where they said the machine was not intended to be a breathing restarter. My prescription on that machine had the Backup Rate turned off. I could hold my breath and the machine would simply not pump any air.
I'm pretty sure that regardless of what the back up rate is set to, if the apnea appears to be an OA based on the results of the PP algorithm, the machine will wait for you to start breathing on your own. And I'm pretty sure the Resmed S9 Adapt reacts the same way: If the apnea in progress appears to be an OA based on the results of the FOT algorithm, the machine will wait for you to start breathing on your own.
On both the Respironics ASV and the S9 Adapt, if the backup rate is set to OFF, the machine is NOT going to respond to an "CA apnea in progress". I'm not sure what each of these machines does if the apnea in progress appears to be a CA and
the back up rate is turned ON. But I believe that if the backup rate is ON, on both the Respirionics ASV and the S9 Adapt, the ASV algorithm will kick in after several seconds of "no flow into/out of the lungs"---provided the apnea appears to be
central in nature.
And it's also important to note that whether a machine will score an intentional holding of breath while awake as an OA or a CA seems to depend on exactly how you hold your breath. In my case, when I run that test, the fake apnea is more likely to be scored as an OA for some reason.
Quote:I am now looking at buying a Resmed S9 Vpap Adapt. Is there a back up rate on these and if it is turned on will it push me to breath when I have stopped?
If the back-up rate of either the S9 Adapt or the System One ASV is turned ON, then the machine will attempt to
trigger inhalations when the breathing rate drops below the target number of breaths. The idea is to
prevent the central apneas from happening in the first place by preventing the CO2 overshoot/undershoot cycle from developing. When the machine detects variations in the breathing pattern---including both slower than expected and shallower than expected breathing, the ASV algorithm kicks in and starts triggering inhalations by cycling between the IPAP and EPAP pressures AND increasing the IPAP (sometimes drastically) while leaving the EPAP alone.
But neither machine is going to respond to an OA in progress by increasing the pressure. Both machines will wait until the OA is over to respond by increasing the EPAP if they're run in AutoEPAP mode.
And, as I said before, I don't know what these machines do if a CA happens without any precursor "tell-tale" changes in breathing patterns. My impression is that if the CA lasts long enough and the back up rate is set to ON, then both the Resprionics ASV and the Resmed VPAP Adapt will try to trigger an inhalation by switching from EPAP to IPAP pressure. And if the CA continues, my impression is that both machines will continue trying to trigger inhalations by switching between EPAP and IPAP at regular intervals determined by the back up rate setting. And both machines will rapidly increase the IPAP pressure (but not the EPAP) as the pressure cycles back and forth between EPAP and IPAP.
Quote:What is this all about where the machine does not pump air when you either hold your breath or stop breathing? I was under the impression that keeping us breathing is what these machines are for.
The PAP part of your therapy is NOT designed to make you breath when an obstructive event occurs. PAP works for obstructive sleep apnea by making it more difficult for the airway to collapse in the first place---in other words, PAP
prevents the vast majority of the obstructive events from happening in the first place, but it is expected that a few events may still get by the defenses. When using a machine that is run in AUTO mode, the machine does NOT increase pressure during an obstructive event; rather the machine waits until the event is over and then increases the pressure to make it more difficult for future events to occur. That is how the machines are designed to work.
The ASV part of your therapy requires additional settings and careful titration. Again, the ASV part of the algorithm is designed
to prevent the vast majority of central events from occurring in the first place. In other words, the ASV algorithm is designed to prevent the CO2 overshoot/undershoot problem from developing in the first place. (It is the CO2 overshoot/undershoot problem that is the main problem that leads to excessive numbers of CAs in the first place.)
In other words, even if an ASV machine is set up in ASV mode, it's only acting as a non-invasive ventilator that will
help stabilize breathing by triggering inhalations when the breathing pattern becomes sufficiently ragged, but is still present. It's not going to blast a huge amount of air down an airway when the airway appears to be obstructed. And it's not completely clear what it's going to do for an isolated CA that is NOT part of an unstable breathing pattern.
The "holding your breath" tests mimic
isolated events rather than genuine unstable breathing patterns, and that can explain why the machine doesn't "do" anything when you intentionally hold your breath while awake. And for some people, the way they hold their breath results in the machine scoring an OA not a CA, and that also can explain why the machine doesn't "do" anything when you intentionally hold your breath while awake.
Quote:I could not help but wonder if it was a way for the whole system that took all my money to also provide a quiet exit strategy for me. Us baby boomers being kind of a glut on the system and all.
Once more, the point behind the machine is to
prevent the vast majority of the bad breathing from occurring in the first place. Even a completely normal person has a few OAs and CAs that occur each night, but these are NOT problematic because they are few in number and don't lead to serious O2 desats or fragmented sleep. The point of your ASV machine is to prevent the vast majority of your OAs, Hs, and CAs from happening in the first place rather than "treat" the events as they happen. If too many OAs, Hs, and CAs are occurring when you are using your machine, then the settings on the machine are not yet optimally set. In your case, if the Backup rate on your Respironics ASV machine is set to OFF, that may be interfering with the machine's ability to properly treat the central part of your sleep apnea. And that's why you need to talk to the sleep doc about why the DME thinks prescription says "back up rate = off."