Bipap questions

[Clinte89]

Hello all I went to my sleep doctor and he recommend me change to a bipap machine and said that I could use a backup rate to get rid of central but we will try bipap for a while to see how that does along with medication to do something with a nerve to keep me breathing. So my question is I am dealing with my dme about this and seeing if they will work with me to trade out my cpap ds260 machine. I do not want to get screwed if they do agree to work with me. So what machine do I need for the option of a backup rate. I may not need it but it's costing me a good bit of money going to a different machine and all the sleep tests. So I would like to know what I should ask for and what is the absolute machine I should get based on that info. If I have to get my doc to specify a machine I can as he just put bipap down. thanks for the info and help

[Pugsy]

Get this machine.
Model 960 PR System One 60 Series BiPap AutoSV advanced (it's what we call an ASV type of machine)....and it will work with your existing humidifier.
It offers the back up rate as well as dealing with the centrals when they pop up.
https://www.cpap.com/productpage/pr-60- ... anced.html
It's full data machine and software (Sleepyhead and Encore) is available.

[Clinte89]

Ok thanks. I'll have to talk to them about that. They said they need the doctors notes. I think they are full of crap.

[JDS74]

The only BiPap machines that Respironics makes with a backup rate are the BiPap S/T and the BiPap AutoSV

Both are quite expensive. The AutoSV is more flexible in setting up and is Respironics first line in the treatment of CSA and complex sleep apnea.

Your doctor may be thinking of the BiPap Auto model 760 which doesn't have a backup rate.
The AutoSV is the model 960.

That is a big jump in technology.

Edit: Typos corrected

[Clinte89]

Should I talk to him and have him specify that model? I am already gonna have to pay a lot of money for the new machine

[palerider]

The only BiPap machines that Respironics makes with a backup rate are the BiPap ST-A and the BiPap AutosSV.

prs1 doesn't make a st-a model, you're thinking about the bipap S/T.

the ST-A is the resmed S9 VPAP ST-A

[Pugsy]

Yes...just have the doctor specify that model (the 960). It will eliminate a lot of confusion.
The PR S1 660/760 doesn't have a back up rate available so it is totally out.
And I don't think that the PR S1 BiPap S/T (forget which model number it is) will do what you need in terms of treating the centrals...it does have a back up rate but doesn't have the speedy response to centrals that the 960 does.
It might do the job and it might not and it is still nearly as expensive as the 960 is...and I know the 960 will cover your needs...both the back up rate and the speedy response to centrals.
It's going to be expensive anyway you go so might as well get for sure what you need instead of maybe what you need.
The BiPap S/T...might get the job done but then again it might not and it's not that much less expensive.

[cnaumann]

I concur with the simple answer to what machine to get, the DS960 should give you excellent results.

A little background. There are basically three classes of PAP (Positive Airway Pressure) machines. Each class has its own prescription code. The three classes are CPAP (single pressure), BiPAP (different pressure for inhaling and exhaling), and BiPAP with Backup rate (BiPAP with the ability to initiate a breath if you do not). Each class is a substantial jump in price.

In the last category, BiPAP with Backup, there are two main subclasses depending on how the backup breathing is activated. One subclass is S/T (spontaneous / timed), the other is subclass is ASV (auto/adjustable servo ventilation). The S/T subclass will initiate a breath at a fixed rate if you do not breathe on your own. The ASV will try to initiate a breath at a rate based on your breathing pattern. The DS960 is an ASV machine, but it also allows you to select a fixed backup rate if you desire.

The both the S/T machines and the ASV machines are useful for treating Central Sleep Apnea. The ASV machines are really the front line for treating Central Sleep Apnea, however, there are some conditions such as COPD or Obesity Related Hypoventilation Syndrome where ASV is contra-indicated. There is really no difference in price in the two subclasses, and there is usually no difference in insurance coverage requirements.

BiPAP with backup rate machines are quite expensive, often retailing for over US$5,000. They can be purchased new on the internet for around $3200. It is also possible to find them ‘open box’ or used from around $1500.

My insurance requires that I ‘fail a CPAP trial’ in order to be eligible for BiPAP coverage, and to ‘fail a BiPAP trial’ in order to be eligible for a BiPAP with a backup rate class machine.

[palerider]

In the last category, BiPAP with Backup, there are two main subclasses depending on how the backup breathing is activated. One subclass is S/T (spontaneous / timed), the other is subclass is ASV (auto/adjustable servo ventilation). The S/T subclass will initiate a breath at a fixed rate if you do not breathe on your own. The ASV will try to initiate a breath at a rate based on your breathing pattern. The DS960 is an ASV machine, but it also allows you to select a fixed backup rate if you desire.

the main difference in the S/T and the ASV is that the S/T doesn't vary ipap on a breath by breath basis to maintian a target minute vent rate, the ASV does, not just giving a set breath after a set time, but assisting breathing as necessary to maintain the ventilation level..

[cnaumann]

the main difference in the S/T and the ASV is that the S/T doesn't vary ipap on a breath by breath basis to maintian a target minute vent rate, the ASV does, not just giving a set breath after a set time, but assisting breathing as necessary to maintain the ventilation level..

Yes and no. Their is more to an ASV machine than the backup rate timing, I said that wrong and should have been more clear. ASV machine do vary IPAP on a breath by breath basis to try to maintain a parameter. I think the parameter is average peak flow rate on the Philips Respironics machines and something else (average tidal volume?) on ResMed machines. This is a very useful feature for stopping periodic breathing as well as treating central apneas.

However, ASV machines do not target a preset minute vent rate. That feature is called AVAPS (Average Volume Assured Pressure Support) by Philips Respironics and maybe something a little different by ResMed. It is a feature actually found on some S/T machines.

The key difference is that the ASV machines set their targets based on your average breathing rate, where as AVAPS sets their targets on an external parameter. If your average breathing rate is not adequate, ASV is contraindicated.

[palerider]

the main difference in the S/T and the ASV is that the S/T doesn't vary ipap on a breath by breath basis to maintian a target minute vent rate, the ASV does, not just giving a set breath after a set time, but assisting breathing as necessary to maintain the ventilation level..

Yes and no. Their is more to an ASV machine than the backup rate timing, I said that wrong and should have been more clear. ASV machine do vary IPAP on a breath by breath basis to try to maintain a parameter. I think the parameter is average peak flow rate on the Philips Respironics machines and something else (average tidal volume?) on ResMed machines. This is a very useful feature for stopping periodic breathing as well as treating central apneas.

However, ASV machines do not target a preset minute vent rate. That feature is called AVAPS (Average Volume Assured Pressure Support) by Philips Respironics and maybe something a little different by ResMed. It is a feature actually found on some S/T machines.

The key difference is that the ASV machines set their targets based on your average breathing rate, where as AVAPS sets their targets on an external parameter. If your average breathing rate is not adequate, ASV is contraindicated.

actually, just yes.
to simplify:
adapt (ASV):

Ventilation to a moving target
To determine the degree of pressure support needed, the adaptive servo-ventilation algorithm continuously calculates a target ventilation. Based on respiratory rate and tidal volume, the target is 90% of the patient’s recent average ventilation—that means that ventilation can vary gradually and naturally over the course of the night.

ST-A (ivaps)

Unlike other ventilation modes that only target tidal volume, iVAPS targets alveolar ventilation, accounting for anatomical dead space to ventilate the patient more effectively. iVAPS provides an intelligent Backup Rate (iBR)
when necessary while maximizing the patient’s opportunity to spontaneously trigger the device

the prs1 960 and avaps are similar in their differences and what they target. there's also a difference in st and st-a.

[cnaumann]

From http://www.healthcare.philips.com/pwc_h ... ochure.pdf

Servo ventilation (SV) algorithm
• Clinically-proven5 SV algorithm monitors peak flow and
changes pressure support breath by breath to stabilize the
breathing pattern
• By establishing a targeted peak flow, the SV algorithm can
rapidly normalize unstable breathing patterns with quick
adjustments of pressure support

The PR DS960 is an ASV machine. The PR DS960 does not target Minute Vent Rate. It targets peak flow. Therefor ASV machines do not necessarily target MV.

It seems that I was mistaken about the ResMed machine. I swear I read something different about how their algorithms operated, but of course now I can't find it.

I also read 'preset' into your description. Some of the S/T machines (with AVAPS) allow you to set a MV as a parameter and they adjust IPAP accordingly, but not on a breath by breath basics. ASV do not allow you to set a MV as a parameter. But apparently ResMed's ASV machines do target the patient's recent MV.

In all cases, if your average breathing is inadequate, the use of ASV is contraindicated.

[palerider]

The PR DS960 is an ASV machine. The PR DS960 does not target Minute Vent Rate. It targets peak flow. Therefor ASV machines do not necessarily target MV.

I welcome your education upon having dug up some comparisons about how the two machines work.

(and, if "peak flow" doesn't translate into minute vent... then what DOES it translate into?

[cnaumann]

"peak flow" doesn't translate into minute vent... then what DOES it translate into?

It does not really translate into anything. It is a little like asking how peak speed translates into distance traveled.

Peak flow probably correlates well with tidal volume (the integral of positive or negative flow should be tidal volume), tidal volume times respiration rate gives you the vent rate... but you need more information before you can translate peak flow into minute vent rate.

Most of my objection to your post was that I mistakenly read it to say '[ASV] maintain[s] a preset target minute vent rate'.

Your ability and willingness to argue over minutiae reminds me of me.

[palerider]

"peak flow" doesn't translate into minute vent... then what DOES it translate into?

It does not really translate into anything. It is a little like asking how peak speed translates into distance traveled.

Peak flow probably correlates well with tidal volume (the integral of positive or negative flow should be tidal volume), tidal volume times respiration rate gives you the vent rate... but you need more information before you can translate peak flow into minute vent rate.

Most of my objection to your post was that I mistakenly read it to say '[ASV] maintain[s] a preset target minute vent rate'.

Your ability and willingness to argue over minutiae reminds me of me.

well, if you don't care about posting correct information, or correcting misinformation, then *shrugs* w/e

*waves*