(12-17-2013, 05:37 PM)pdeli Wrote: - I'm now wondering if I made a mistake pushing for the Bi-Pap to replace the C-pap. In looking at my C-Pap data, I see that my "pressure" on a given day went from a base of 7 to as high as 11.
Maybe, maybe not. The thing is: With the BiPAP, you can always switch it to straight CPAP mode if you prefer. Or with the 560, you can make it act just like a System One APAP by doing nothing more than setting min PS = 0
and max PS = 0
. That small change in settings is all it takes to make the machine use the same pressure on both inhalation and exhalation like your CPAP. And in this setting, you can just use the Bi-Flex setting to mimic whatever A-Flex setting you used to have.
In other words, the System One BiPAP is a more flexible machine than the System One APAP. You can make the BiPAP mimic the APAP, but you can't make the APAP act like a BiPAP.
Quote:The machine is a Respironics System One 560P, RemStar Auto with A-Flex. Mode: APAP 7-13cmH20.
My question is, what is the distinction between the application and results of this machine vs. the Bi-Pap with its 6 IPAP and 16 EPAP ??????
From a previous post, we've determined that your BiPAP's settings are:
- min EPAP = 6
max IPAP = 16
min PS = 0
max PS = 10
Your old APAP was set with
The short answer to your question
- min pressure = 7
max pressure = 13
The biggest difference between the APAP and the BiPAP is that on the APAP when you are exhaling, the pressure is the same as when you were inhaling, while on the BiPAP there are two pressures---one for inhalation (the IPAP) and one for exhalation (the EPAP). And these two pressures do not have to equal each other.
In your case, on the APAP, the starting pressure for the night is 7 = min pressure
setting. And any time you turn the machine off and back on, the pressure is reset to 7cm. And on each and every breath through the night,
- 7 <= current pressure <= 13
The pressure will adjust through the night, but on any given breath, the pressure on the inhalation will be the same as the pressure on the exhalation. (Flex will provide a small, variable decrease in pressure at the start of the exhalation, but by the time the exhalation is complete, the pressure will be back up to what it was during the inhalation.)
On the BiPAP with your BiPAP settings, the starting pressures for the night are:
- starting EPAP = 6 = min EPAP
- starting IPAP = 6 min EPAP + min PS
And any time you turn the machine off and back on, the pressures are reset EPAP = 6 and IPAP = 6. And on each and every breath through the night,
- min EPAP + min PS = 6 <= IPAP <= 16 = max IPAP
min EPAP = 6 <= EPAP <= 16 = max IPAP - min PS
- min PS = 0 <= IPAP - EPAP <= 10 = max PS
The biggest difference between the BiPAP and the APAP is that on the BiPAP, the IPAP does NOT have to equal the EPAP on every single breath, and with your settings, it is possible for IPAP = 16 and EPAP = 6 since max PS
= 10 = 16 - 6.
The way the BiPAP works is this: When you are inhaling, the machine increases the pressure to the current IPAP pressure; as soon as your exhalation starts, the pressure is decreased to the EPAP pressure, which can be quite a bit less than the IPAP. The cycle of increasing the pressure at the start of each inhalation and decreasing it a the start of each exhalation continues for each and every breath you take whenever your IPAP > EPAP. The BiPAP Auto algorithm is very similar to the APAP's Auto algorithm and it allows both the IPAP and EPAP pressures to change during the night. But in the BiPAP Auto algorithm, sometimes the machine will only increase the IPAP pressure in response to events; sometimes it will only increase the EPAP; and sometimes it will increase both the IPAP and EPAP pressures.
The point of having two different pressures on a BiPAP is that for many people, the switch between IPAP on inhalation and EPAP on exhalation (when IPAP > EPAP) makes breathing against the positive air pressure seem more natural. The drop to EPAP during the entire exhalation also makes it easier for some people to exhale against the pressure. (The pressure relief provided by Flex does not last for the full exhalation.) And in general the average pressure level the body has to deal with is lower because roughly half the night, you're exhaling at EPAP. And this can reduce the tendency to swallow air, which reduces aerophagia. For people who have a tendency to develop pressure induced CAs, the fact that EPAP can be much lower than IPAP can help reduce (sometimes even eliminate) the problem of pressure induced CAs.
A longer, more complete answer to your question: What is the distinction between the application and results of the APAP vs. the Bi-Pap Auto?
requires some understanding of how each of these two machines respond to obstructive apneas, hypopneas, flow limitations, RERAs, and snoring. I'll save that for another post.