Settings for an Aircurve ST-A machine

[CPAPSteve]

So my regular machine is a airsense 19 for her with a setting of 11.4 min and a 20 max pressure with no EPR.

I have this practically brand new Aircurve 10 ST-A machine that I wanted to give it a try to see how it’s different.

What mode and settings should one use to closely match what my airsense 10? I understand that the ST-A unit is a really specialized unit that isn’t really used to treat just sleep apnea but for those with COPD or other severe respiratory issues. It seems like a ventilator more than a CPAP machine.

I kinda played around with iVAPS and ST modes but there was also a CPAP, S, T and one other mode.

Cpap mode is self explanatory but the other modes while I get mostly what they do that there are a lot of settings I am clueless about. Target va, volume, tmin/tmax rise time, cycle...

So many things on this machine.

[raisedfist]

I understand that the ST-A unit is a really specialized unit that isn’t really used to treat just sleep apnea but for those with COPD or other severe respiratory issues. It seems like a ventilator more than a CPAP machine.

Because it is a non-invasive ventilator. Using iVAPS mode to treat obstructive sleep apnea absent any other issues is like using a boulder to crush an ant.

You won't be able to mimic the settings of your APAP, as the algorithms exist for entirely different purposes. The IPAP varies in iVAPS to maintain a target alveolar ventilation rate that you program in. It doesn't respond whatsoever to hypopnea, obstructive apnea, flow limitation or snoring. The EPAP is static.

[CPAPSteve]

Yes I knew that the ST-A models weren't meant mainly to treat sleep apnea but actually respiratory diseases and issues

I only ask for my own curiosity. I have kinda messed around with the settings and it is bizarre that the machine is trying to breathe for me but if I relax and just let it do it’s thing my breathing eventually syncs up with the unit.

[Pugsy]

Best you can probably do with it is S mode...fixed bilevel mode.
There's no auto adjusting on it at all like the apap mode.

I have played with the ST model...I didn't like the mode where the timed breaths kick in...really annoying.
So I used S mode...essentially fixed bilevel. The drawback to it is your EPAP has to be a bit higher than you can get by with using an apap.
I did adjust rise time (I think it was rise time) to be more in tune with my own respiration rate...so you can tweak some of those comfort settings a bit and smooth out the transition.

Since you don't use EPR...then you may want to keep the PS at zero or maybe 1... unless you find you like it.

Obviously this machine can do stuff you don't need to have done...and it won't do some stuff that the apap does...but it's a decent enough spare machine if a person is happy with fixed pressures of some sort.

[raisedfist]

Yes I knew that the ST-A models weren't meant mainly to treat sleep apnea but actually respiratory diseases and issues

I only ask for my own curiosity. I have kinda messed around with the settings and it is bizarre that the machine is trying to breathe for me but if I relax and just let it do it’s thing my breathing eventually syncs up with the unit.

You can be the driver of breathing if the machine is set correctly. You can test it while awake by setting your height, change target alveolar rate up or down until you see the Vt value change to 6ml/kg, and then set the target patient rate to 15bpm. Leave PS min and PS Max, and all other settings, at the default value. The target rate is most important for being in sync with the machine. If you breathe below 2/3rds the set rate, it will force breaths on you, which is probably what's happening.

[CPAPSteve]

I tried playing with iVAPS mode and the self learning target values and it came up with 5.4L/minute plus a bunch of other values (BMP I believe is 15 which I changed to . EPAP value was 12 with a PS of 10. Figured these settings would be close to what my APAP is (11-20 pressure range). Strapped on a mask and because I was tired I fell asleep.

It was odd for a machine to breathe for me but I fell asleep for an afternoon nap and while it was somewhat weird feeling that I must’ve been so tired to sleep through it all. Wife said it had a breathing machine whooshing/clicking noise but I stayed sound asleep lol.

Woke up and it recorded 0 events.

Is it dangerous to use in iVAPS or ST mode? CPAP of course I know is safe.

[raisedfist]

I tried playing with iVAPS mode and the self learning target values and it came up with 5.4L/minute plus a bunch of other values (BMP I believe is 15 which I changed to . EPAP value was 12 with a PS of 10. Figured these settings would be close to what my APAP is (11-20 pressure range). Strapped on a mask and because I was tired I fell asleep.

It was odd for a machine to breathe for me but I fell asleep for an afternoon nap and while it was somewhat weird feeling that I must’ve been so tired to sleep through it all. Wife said it had a breathing machine whooshing/clicking noise but I stayed sound asleep lol.

Woke up and it recorded 0 events.

Is it dangerous to use in iVAPS or ST mode? CPAP of course I know is safe.

What do you mean by the machine breathing for you? Bi-level machines assist or augment your own breathing, they don't breathe for you unless you fail to spontaneously trigger a breath or breathe below the set backup rate. It's not a life support machine. You can check the therapy data for your "spontaneous trigger %" result. You have to set a PS min and PS max in iVAPS mode. You can't equate EPAP or EPAP range with a pressure support or pressure support range. Just like you can't equate CPAP with bi-level therapy.

Neither mode is likely to be dangerous, but fiddling around when you don't know what you're doing, or without a reason to use either mode, is ill advised. If you promise to sign a waiver, I can recommend some settings that actually could be dangerous?

[CPAPSteve]

.

[CPAPSteve]

I tried playing with iVAPS mode and the self learning target values and it came up with 5.4L/minute plus a bunch of other values (BMP I believe is 15 which I changed to . EPAP value was 12 with a PS of 10. Figured these settings would be close to what my APAP is (11-20 pressure range). Strapped on a mask and because I was tired I fell asleep.

It was odd for a machine to breathe for me but I fell asleep for an afternoon nap and while it was somewhat weird feeling that I must’ve been so tired to sleep through it all. Wife said it had a breathing machine whooshing/clicking noise but I stayed sound asleep lol.

Woke up and it recorded 0 events.

Is it dangerous to use in iVAPS or ST mode? CPAP of course I know is safe.

What do you mean by the machine breathing for you? Bi-level machines assist or augment your own breathing, they don't breathe for you unless you fail to spontaneously trigger a breath or breathe below the set backup rate. It's not a life support machine. You can check the therapy data for your "spontaneous trigger %" result. You have to set a PS min and PS max in iVAPS mode. You can't equate EPAP or EPAP range with a pressure support or pressure support range. Just like you can't equate CPAP with bi-level therapy.

Neither mode is likely to be dangerous, but fiddling around when you don't know what you're doing, or without a reason to use either mode, is ill advised. If you promise to sign a waiver, I can recommend some settings that actually could be dangerous?

The slightest effort to breathe in results in the machine "helping" push air into me. Upon my inhaling that just before I stop inhaling that the machine lowers the pressure and then I exhale naturally only to repeat the cycle all over again. Where would I see the spontaneous trigger % result in SH?

It would appear SH doesn't pull all the data and display it properly for this particular machine.

Any suggestions on what the ideal settings should be set to for this machine so that I can have it ready as a backup?

As previously stated my AS10 autoset has a min pressure of 11.4 and a max pressure of 20. I used to use an EPR of 3 BUT I stopped using EPR because I didn't want to have my min pressure go below my ideal minimum pressure.

Forgive my ignorance here but how is S mode vs. iVAPS different? iVAPS varies the ipap pressures and given some of the information on the unit's screen that iVAPS appears to push a specified minimum volume of air into a person to keep them properly ventilated. In my case it shows 5.4 l / min. I assume that is how much air I have to breathe in based on the auto detect algorithm that I first ran.

There is also this mode called PAC mode. Clueless on what that is or what it means. I will start looking for a manual book on apneaboard...

Is there much demand for a ST-A machine here? What would be a fair price to let this one go or should I keep it as a spare?

[Jas_williams]

The Aircurve ST I used worked fine with Oscar. The pressure line was not availiable for some reason but mask pressure was there and all the sleep stats

[raisedfist]

The slightest effort to breathe in results in the machine "helping" push air into me. Upon my inhaling that just before I stop inhaling that the machine lowers the pressure and then I exhale naturally only to repeat the cycle all over again. Where would I see the spontaneous trigger % result in SH?

That sounds to me like the "trigger sensitivity" setting should be turned down then. You can't see that that statistic in SleepyHead - only on the machine itself under the data summary, or in ResScan.

It would appear SH doesn't pull all the data and display it properly for this particular machine.

Sort of -- it's not a widely used machine. SH is largely intended for OSA patients.

Any suggestions on what the ideal settings should be set to for this machine so that I can have it ready as a backup?

As previously stated my AS10 autoset has a min pressure of 11.4 and a max pressure of 20. I used to use an EPR of 3 BUT I stopped using EPR because I didn't want to have my min pressure go below my ideal minimum pressure.

Unless you change the machine to CPAP or S mode, the machine has no value to you.

Forgive my ignorance here but how is S mode vs. iVAPS different? iVAPS varies the ipap pressures and given some of the information on the unit's screen that iVAPS appears to push a specified minimum volume of air into a person to keep them properly ventilated. In my case it shows 5.4 l / min. I assume that is how much air I have to breathe in based on the auto detect algorithm that I first ran.

I think you just answered your own question lol. S mode does not auto adjust the IPAP or EPAP for any reason whatsoever- it is a user set IPAP and EPAP.

There is also this mode called PAC mode. Clueless on what that is or what it means. I will start looking for a manual book on apneaboard...

PAC mode is pressure assist-control mode. It is almost exclusively for neuromuscular disease and pediatric patients who have severe breathing problems - they have a hard time triggering, and sustaining, an inhalation. It uses a fixed inspiratory time that determines the length of time at IPAP, and also this determines the breath cycling criteria. This is considered a true ventilator mode.

Is there much demand for a ST-A machine here? What would be a fair price to let this one go or should I keep it as a spare?

While not too common, there are people here with respiratory illnesses. Not sure what a fair price would be...I've never seen this one on the secondary market more than a few times. The older S9 ones I have seen quite a few times though.

[CPAPSteve]

Wow thanks for all the detailed information. I tried to sleep last night using “S” mode and while it was doable that I much prefer my AS10 autoset.

Interesting about PAC mode being the truest to a ventilator. I feel all the modes except for cpap felt like a ventilator.

Any recommendations on pressure settings for S mode given my settings on my AS10 autoset?

Thanks

[raisedfist]

Wow thanks for all the detailed information. I tried to sleep last night using “S” mode and while it was doable that I much prefer my AS10 autoset.

Interesting about PAC mode being the truest to a ventilator. I feel all the modes except for cpap late like a ventilator.

Any recommendations on pressure settings for S mode given my settings on my AS10 autoset?

Thanks

The biggest drawback to S mode is that you have to set IPAP and EPAP for the worst case scenario, since neither of those adjust in S mode, instead of APAP or VAuto where you can set a lower but effective min pressure and if the machine wants to increase pressures while you're asleep it will and hopefully not cause you to wake up (it usually does not).

I'm not good on prescription conversions so maybe someone else will chime in to help you with that. My guess is you'd keep EPAP high enough to keep your airway open, and then IPAP becomes the small hammer to finish off the snoring, flow limitation and hypopnea. But ideally you don't want a pressure support (ps) of more than 4-5, maybe 6, unless you have lung disease. So if the data indicates you need an increase in IPAP, generally you'd increase the EPAP by the same amount to maintain the level of PS. If I had to guess at random, maybe something like 14 IPAP / 10 EPAP sounds pretty reasonable as a starting point. If you have zero OA at EPAP 10, you could try backing off a bit then; generally the lowest pressures that get you the results are what is desired.

[palerider]

Any recommendations on pressure settings for S mode given my settings on my AS10 autoset?

Thanks

They don't correspond.

But, if you want whatever's closest, figure out your max pressure, set IPAP to that, and set EPAP to 3 less.

[CPAPSteve]

Thanks guys, I suspected that the EPAP would be my min pressure and IPAP be somewhere between my average or max pressure. Looking at SH data it seems that most nights my pressure is around 14 so I guess EPAP should be set to 11.4 and IPAP to say 15 ought to be more than enough then.

I doubt I will mile up my ST-A machine. Nothing wrong with my AS10. Using the ST-A was purely for trying out a bi-level / ventilator like machine.

If anyone knows someone looking for one I am still offering it up for sale. Reasonable offers as I have no idea what these things are worth slightly used.

Thanks