VAuto Journey

[optimalsleep]

Stop breathing for at least 10 seconds

[lbl82]

Stop breathing for at least 10 seconds

So if I stop breathing for 10 seconds that would be 1 mild central apnea event?

[optimalsleep]

depends on how many you have per hour..... and how long they last. Your ResScan software will show that. Go back and read it. And do what I suggested about expanding your flow rate chart. According to your software left hand chart you have 7 per hour.... every time I checked my flow rate chart it was correct. You central apneas are called clearway apneas.

[SarcasticDave94]

That's how it would be counted, yes. It must be for 10 seconds minimum. Obstructive means physical blockage, the throat collapses type. Central is that you do not breathe, no effort and no physical blockage. Centrals can be what I call pre-existing, meaning they'll show on the sleep study pre-treatment, then treatment emergent are ones that CPAP machines cause due to carbon dioxide wash out, and idiopathic meaning unknown cause.

[optimalsleep]

great video on Central Apnea


https://www.youtube.com/watch?v=1OQFESwNXm0

[lbl82]

Continue to lower your PS.  I would also go with the EPAP of 10 for now.
Set PS = 2, we get to PS = 0 before we are done.

Higher PS improves/increases your breathing efficiency, This improves/raises your O[sub]2[\sub] sats and decreases your CO[sub]2[\sub] sats.  When your CO[sub]2[\sub] reaches your apneic threshold you have central apnea, at least one form of it.  Lowering your PS (and pressure) are measures to see if we can control this cause and effect.  While it usually works, this is what we need to know to suggest the best treatment for you.  

Central apnea is always consistent, in an odd way.  It is consistently inconsistent!!  This means that it often can and does jump all over the place, you need to see what happens over a week and the same settings to see if settings actually have an impact.  We can get an idea that it is working but cannot tell for sure until we see the results over a week period. In the meantime, we want to see what happens as we gradually lower your PS.  Just because we lower it and you see a jump in AHI does not mean it is not working when looking at single daily screenshots.

I don't understand the PS.  What does pressure support have to do with IPAP and EPAP? Also, how does the ramp feature work on a VAuto?  What does it ramp up to since I don't have a minimum pressure?

[Gideon]

Pressure Support is simply the difference between exhale and inhale / EPAP and IPAP pressures.
In 'manual mode "S" or spontaneous mode you set both a fixed EPAP pressure and a fixed IPAP pressure, the difference is referred to as pressure support.
In auto mode you set a
Min EPAP pressure, the BiLevel will not go below this
Max IPAP pressure, the BiLevel will not go above this, and a
PS, the amount that will be added to EPAP to reach the IPAP. The difference between EPAP and IPAP will always be equal the PS.
The auto algorithms will alter the pressures within the above limits.

Ramp
Designed to make the beginning of treatment more comfortable, ramp is available in all modes.
In VAuto, S, ST and T modes the ramp functions as follows:
The EPAP gradually increases from the Start EPAP to the prescribed treatment pressure.
Throughout Ramp, Pressure Support is maintained at the same level as that set for treatment.

[Sleeprider]

The difference between IPAP and EPAP is pressure support. IPAP-EPAP=PS. It's that simple. Without difference in inhale and exhale pressure, there is not pressure support. Pressure support increases pressure along with our inspiratory effort and makes inhale easier, then lower pressure to make exhale easier. Your ramp is set to 20 minutes and the chart does not show the ramp start pressure, but it appears to be about 8.0.

I'll be honest with you, your high pressure settings make no sense to me. Why are you using such high pressure when you have no obstructive events? You are using EPAP min of 15 with PS 3. You want to explore better therapy? Reduce your EPAP min to about 8.0. If we don't see obstructive apnea, we will reduce it further. You don't need this high pressure, and someone really screwed up when your machine was setup. You are incredibly over-ventilated and that is why you have so much central apnea.

[lbl82]

   

Great numbers! The settings I changed from the night before last are: EPAP to 10 from 15, Trigger Sensitivity from Medium to Very High. I also turned the Ramp off last night. I did notice that my Clear Airway to Hypopnea ratio changed.  Relative to my AHI number my hypopnea went up slightly and my centrals went done slightly in my opinion.  If you see my graph from the night before last you'll see what I mean.  I might be interpreting this wrong though.

[Sleeprider]

This is exactly what I expected from lower pressure and will suggest you can go all the way to the minimum pressure settings I suggested previously of 8.0. You still did not have obstructive apnea, but had some hypopnea and CA. As we reduce your pressure, we should see CA reduced, and I suspect the hypopnea are not obstructive in this case, so the should go down as well. I based that conclusion on the fact your flow limitation 95% is still 0.00. Your optimum pressure is lower.