[Treatment] Need help interpreting Oscar data

[Jay51]

You are very welcome.  I think I can understand where you are at right now and what is going on (big picture).  When the RT put in the settings that they calculated and were supposed to work, they hurt your chest and lungs (volutrauma) with the Triology.  The same thing happened to me initially and I have read a post here that a similar thing happened to another 1st time ventilator user.  

You and your RT and Dr.(s) then became very cautious (and rightly so) and went to the opposite extreme:  very conservative treatment and settings.  Right now, using the "ST" mode with EPAP 3, IPAP 12.8 (and PS set at 9.8).  This is tolerable for you, but you are instinctively recognizing that you are probably having more co2 building up in your lungs.  And by your actions of coming to ApneaBoard and asking for help, you are ready for a little bit of advancement in your therapy (very slowly and very carefully).  

With such a low EPAP of 3, it seems like sleep apnea is not much of a concern.  Your most vital concern is adequate ventilation.  Around 12.8 (or roughly 13) may be the maximum tolerable IPAP you can tolerate.  Maybe a bit more.   Pressure support at 9.8 (roughly 10) is some pretty high pressure support; but appears to be working fairly.  

Hopefully, you can get the capnography testing to prove your intuition.  Like Sleeprider said, IVAPS can be more customizable, but with all ventilators, if too aggressive settings are used, pain, and possible damage to the lungs can occur.  Your settings would need to be very conservative in IVAPS when/if you start using it.  Your current settings in ST mode could be roughly switched over to IVAPS with some other minor tweaks.  If IVAPS proved to be intolerable, you could always switch back to these current settings in ST mode.

[OldPolioLady]

I would like to try IVAPS if you and Sleeprider could tell me what settings to use. Thanks

[Jay51]

How tall are you?  (Used for some calculations).

[OldPolioLady]

I am 5'4" tall.

[Jay51]

When you switch to IVAPS mode, transfer all the numbers that you can over from your post #6 here in this thread into the IVAPS mode settings.  What settings now are left blank and need values for?  Those can be calculated.  And 5 feet 4 inches tall is 162.5 cm.  You can round to 162.

[Jay51]

A thought just ran through my mind.  I am probably doing the exact same thing your RT did when they initially programmed your Trilogy that resulted in the "epic fail" that caused pain in your chest like your heart was going to explode.  These calculations "should" work, but very well may not.  

Tonight, sleep with your same ST mode settings again.  A trick my RT used that was the game changer was reducing my values enough so that they were at least tolerable.   I don't want the same thing to happen to you tonight that happened to you when you tried the Trilogy.  

I will try to recalculate some numbers tomorrow to reduce everything by 10%, 20%, or even 25%.  I can plug in 5 foot 3, 5 foot 2, 5 foot 1, and 5 foot 0, etc.  Those values should at least keep you from any volutrauma.  And we can always go up from there based on comfort and your OSCAR charts.  Seems like the safest plan.

[OldPolioLady]

There are 3 values that need to be set in IVAPS mode that I don’t know what they should be. Target Va L/min, Min PS, and Max PS. 
What is the difference between IVAPS and what your trilogy is set to?

[Jay51]

I have played around with some numbers.  

Try Target VA L/Min   4.6  (I am basing this on your previous OSCAR in ST mode showing your median respiratory rate at around 13 and tidal volume median around 460 - I used 450 here).  

Can you check the setting, "EPAP/PEEP" to see if it is set to 4.  I need to know this number to be able to calculate your Min PS and Max PS.  

IVAPS is basically the same as my AVAPS.  Just 2 different brands and a slight difference in their algorithms.  Target VA L/Min is the most important settings for IVAPS.  Also, the iBR (intelligent back up rate) setting is important.  We can try 13 here, but if it seems to fast, then we can lower it.  Also, it the volume of air seems too high for your lungs, we can always adjust and lower the 4.6 value.  

IVAPS may smooth out your respiratory rate, tidal volume, and minute ventilation during sleep.  Most likely when your minute ventilation dips, co2 is building up in your lungs.  By keeping things more steady with less variability, hopefully things will improve.  And most importantly, if anything feels off, or it feels too fast or too powerful, you can always stop for the night and go back to ST mode settings and finish the night and we can look at OSCAR and try to figure out what is happening.

[Jay51]

These are the settings on my Trilogy Evo for comparison.  I like the "auto" settings because they provide flexibility.  

Prescription 1 -
CIRCUIT:  Passive
MODE:   AVAPS - AE
Advanced
SIZE:  Adult
ACTIVE HUMIDIFICATION:  On
Using default calibration
TIDAL VOLUME:  500 ml
MAX PRESSURE:  25 cm/H2o
EPAP MIN/MAX:  4/10 cm/H2o
PS MIN/MAX:       4/20 cm/H2o
PC BREATH:  Off
INSP. TIME: Auto
BREATH RATE:  Auto
TRIGGER TYPE:  Auto - Trak
TRIGGER SENS.  Auto
FLOW CYCLE SENS.  Auto
RISE TIME:  3 
AVAPS SPEED:  5 cm/H2o

If you can set the EPAP/PEEP value to 3, then put in 3.  If it won't go that low, put in 4.   
If 3, then put Min PS as low as it will go and put Max PS at 11 (10 would make your settings as identical as possible to your ST settings, but adding one more to make it 11 might be worth it).  
If 4 is what you put in, then use the lowest number you can for Min PS and put in 10 for Max PS.  I have tried to keep your settings as close to the current settings you are using in ST mode.  Hopefully it will be a smooth transition to IVAPS.

[OldPolioLady]

Epap is set to 3. min PS can be set to 0. I don’t think it should be 0. What value do you suggest?