RE: 3 Months on CPAP, still tired despite Dr saying my apnea is controlled
Higher tidal volume is good to a point but it is a balancing point. If it is too low your body will work hard to get enough air(high effort, high respiration rate). If it is too high your body will decrease respiration effort (slow breathing, paused breaths, central apnea).
It is also a balancing point that can change as your body adjusts. If your body has been struggling to breath for 20 years and you open airways with cpap and increase flow with ps then it can take a while to adapt to improved flow (treatment emergent central apnea) but after doing so there may still be room for more minor improvement.
RE: 3 Months on CPAP, still tired despite Dr saying my apnea is controlled
I don’t know much about the Ti Max, Trigger and Cycle yet but the current settings are
Easy-Breathe: On
Ti Max: 3.1
Ti Min: 0.3
Trigger: Low
Cycle: Med
RE: 3 Months on CPAP, still tired despite Dr saying my apnea is controlled
Timin and max are fine, they don't apply in your situation.
I would change trigger to medium (which would have been default) and cycle can stay same.
RE: 3 Months on CPAP, still tired despite Dr saying my apnea is controlled
Hey all. I just want to clarify something for myself since I’ve been reading a ton about UARS and flow limitations.
I essentially need a higher pressure in order clear up the flow limitation? And the point of getting the BiPAP is to be able to do that without increasing the EPAP like I would have to on the CPAP.
RE: 3 Months on CPAP, still tired despite Dr saying my apnea is controlled
You are correct. The bi-level CPAP will allow for a greater pressure difference between the EPAP and IPAP pressures. You can maintain your EPAP pressure but increase the IPAP by setting the PS value. Just make sure that the IPAP maximum setting is equal to or higher than the value of adding the EPAP and the PS pressures together.
RE: 3 Months on CPAP, still tired despite Dr saying my apnea is controlled
The bilevel pressure support actually comes in behind your spontaneous effort to assist getting to your peak flow. CPAP pressure can get uncomfortable at higher pressures, but bilevel pressure offers a contrast between inspiration and expiration. CPAP pressure cannot change respiratory volume or cause people to take a deeper breath. A more extreme example, people with central apnea need ASV which provides a lot of pressure during inspiration when spontaneous effort is weak or absent. They would not get a breath at all with just CPAP pressure, but they can have normal respiration with the pressure support of ASV. With UARS an analogy might be to think of a car trying to go over a hill using a fixed throttle. As the car climbs it reaches a maximum speed and may even slow down. Bilevel pressure is like using the throttle in that car to keep it climbing over the hill without losing speed, then letting up on the throttle to go down the other side.
RE: 3 Months on CPAP, still tired despite Dr saying my apnea is controlled
(02-09-2022, 10:56 AM)Sleeprider Wrote: The bilevel pressure support actually comes in behind your spontaneous effort to assist getting to your peak flow.. With UARS an analogy might be to think of a car trying to go over a hill using a fixed throttle. As the car climbs it reaches a maximum speed and may even slow down. Bilevel pressure is like using the throttle in that car to keep it climbing over the hill without losing speed, then letting up on the throttle to go down the other side.
Thank you. That helped make a lot more sense in my head!
RE: 3 Months on CPAP, still tired despite Dr saying my apnea is controlled
That analogy to me is more like an ASV than a basic bilevel, a basic bilevel doesn't change the throttle it just provides more pressure support all the time.
To stay on the theme I would explain a bilevel as the car having more horsepower that allows it to climb the hill efficiently rather than getting stuck or slowing down significantly.
That might not seem as elegant a solution as a variable throttle (ASV) but the reality is we already have a built in throttle. When breathing is tough our respiration effort and rate increase. When it is easy respiration rate and effort decrease. The extra pressure support from a bilevel gives us the ability to breath without significant issue when restriction is present and then when breathing is easy our body relaxes.
RE: 3 Months on CPAP, still tired despite Dr saying my apnea is controlled
Thanks. Getting used to the greater PS for now, got my apneas under 2 at 11/6.4 so I'll stick with that for a few nights before dropping some more charts on here. Still having the flattened curve on the flow rate so I'm guessing I'll definitely be needing to bump IPAP pressure up.
RE: 3 Months on CPAP, still tired despite Dr saying my apnea is controlled
As I read more and more about UARS and symptoms that seem more specific to it, my eyes are opening. Seems to be a lot of correlation to low blood pressure, anxiety, POTS, cold bands and feet which I have all of the above. I have an upcoming appointment with an ENT that I’ve been waiting 6 months for and I’ll definitely be bringing flow limitations up.
I’m curious to know if any of you have come across this answer or not. Is it typically a higher IPAP that fixes the flow limitation or is the greater PS that fixes it? I’ve read the Our Collective Wisdom article and it seems like there’s real known reason that BiPAP is better for people with flow limitations but on average he says that the PS is between 5-6, even going as high as 12
