Please Help..Bi-PAP AVAPS - Calling SWS..

General Discussion on any topic relating to CPAP and/or Sleep Apnea.
-SWS
Posts: 5301
Joined: Tue Jan 11, 2005 7:06 pm

Re: Please Help..Bi-PAP AVAPS - Calling SWS..

Post by -SWS » Fri Jul 02, 2010 8:32 am

Hello, Vikingblade. I am so sorry to hear you're having difficulties getting your AVAPS set up right.
vikingblade wrote: over the last few weeks, i have felt the need to increase my ipap pressure. i was at 18 for a long time, and recently been having alot of difficulty getting a deep breath during the day and in bed. so.. went to 20, 22, 24.. now 26. it finally felt like i was being given a deep breath without me needing to assist much. however, after a couple nights at that pressure, i started feeling kinda strange during the day..shaky and feeling like i couldnt breath very well.

another thing.. i have my tidal volume at 600, but, ipap doesnt move a bit..thought it wasnt working. then started thinking.. maybe at my ipap pressures, im already over the 600. so..i looked at the monitor screens and saw something called vte..exhaled tidal volume.. im thinking this basically tells me what the tidal volume im currently at using my pressures..is this correct?? if so, my tidal volume is like 1100 at an ipap of 26!
It sounds to me as if your lungs are overinflated at those pressures, vikingblade.


vikingblade wrote: i really cant seem to go higher than like 2.2 without it feeling suffocating.
Well, supposedly the reason restrictive or neuromuscular patients need to extend Ti, is so that they have enough time to fully inflate their lungs. However, at your over-inflating pressures (likely), adding more time for lung inflation is counterproductive. When you over-inflate your lungs that way, you are essentially mimicking what happens with chronic COPD/emphysema patients: the disease causes their lungs to hyperinflate; and that, in turn, often leaves them with a suffocating or shortness of breath feeling:

http://www.healthcentral.com/copd/c/192 ... treatments
The basic cause of shortness of breath in folks with COPD/Emphysema is hyperinflation. In the emphysema component of COPD, the lungs actually get bigger. They are over-inflated and stretched out and have lost a lot of their elastic recoil (the ability to spring back when expelling air).



Unfortunately, you cannot rely on comfort alone to ascertain optimal IPAP----since subjective feedback can be paradoxical in the case of over-inflation. If you repeatedly and consistently over-inflate, then you can experience that seemingly paradoxical shortness of breath. And if you try to use that paradoxical symptom as your primary fine-tuning or feedback mechanism, it's going to send you in the wrong and opposite direction regarding how much to inflate your lungs...

You really need to get in the loop with pulmonary/RT type specialists with actual ventilator experience---ones who can get you set up in a properly-equipped lab setting. I know that's not the kind of answer you were hoping to hear, vikingblade. But unfortunately it's the best and most truthful advice I can give.

Good luck, my friend...

vikingblade
Posts: 11
Joined: Sun May 23, 2010 12:41 am

Re: Please Help..Bi-PAP AVAPS - Calling SWS..

Post by vikingblade » Fri Jul 02, 2010 2:38 pm

thanks sws.. makes sense. another thing i wanted to mention is after a night on the machine, i feel pretty good for a few hours. my theory right now is... like yours that my recent increase in pressures and extended inhale times has caused some overinflation and increased my lung volume. problem is.. my accessory breathing muscles are not accustomed to inflating the new volume and hence tire out quicker than they used to. now, since i dont have copd and these recent symptoms im experiencing are likely from hyperinflation due to recent higher ipap pressures.. can that be reversed by simply cutting back on the ipap pressures? i know you see the need for professional help..and i tend to agree. however, its now the holiday weekend and short of going to the er[which i dont want to do] im pretty much on my own for the next few days at least. so..my plan tonight and for the next few is going to be to lower my ipap to prob 22 or lower and keep my inhale time at 2.0 max. is there an advantage to lowering or increasing my bpm? again, i understand you not wantting to advice me in this situation, but, like said, im gonna do something either way. any direction you can point would be appreciated. thanks again