Sharhamm wrote:Did you see anything in the graphs? I was not awake and thinking about breathing, I was "awakened" with intense blowing and was unable to exhale. It seemed as if the machine thought I was still inhaling. My pressures are 12/16 and these events wakened me.
I don't see anything unusual in these graphs.
It's possible that a glitch in your breathing woke you up. Or it's possible you woke up, then had the glitch in the breathing, and then
really woke up. What I mean by that is that waking up is a process and one part of that process is changing the control of the breathing from the autonomous nervous system (night time breathing) to the voluntary nervous system (daytime breathing). And that transition is not always completely smooth. Another part of the process of waking up is coming to a fully conscious, wakeful state. Studies have shown that most people will NOT remember waking up at night
if the length of the wake is less than about 5 minutes. In other words, it takes a while for us to get to full consciousness where we're capable of remembering things. If you were in the
process of starting to arouse anyway and the breathing glitch happened while you were in the process of waking up, your conscious memory of the events could easily be "the breathing glitch woke me up" simply because you were not aware that your brain was already transitioning to a wake state when the breathing glitch happened.
As for the sensation that you could not exhale fully and that the problem was caused by the machine failing to cycle from IPAP to EPAP: These machines are very, very good at detecting our inhalation/exhalation patterns, but they are not
perfect. It is possible that the machine missed the beginning of the exhalation for some reason just as you were starting to wake up anyway. It's possible that you are sensitive enough to the change in IPAP/EPAP pressures that when the machine failed to detect an exhalation, that your body picked up on that fact as "something unusual" and woke up more than it ordinarily would have. Or it's possible that your sensation of the pressure not going down was just a sensation. In order to sort out what
might have happened, we'd need to see the following two graphs lined up together:
The flow rate graph at the time of the incident zoomed in to show roughly 3-5 minutes of breathing.
The high resolution Mask Pressure curve that the Resmed machines record zoomed in to show the same 3-5 minutes of breathing.
The Mask Pressure curve (which ONLY the Resmed machines record) shows exactly what is happening to the pressure
at the mask end of the hose during each and every breath. You can physically see how the EPR algorithm works on the Resmed CPAP/APAPs and you can physically see how and when the switch between IPAP and EPAP occurs on the Resmed VPAPs.
It's been since Dec. 16 and I have only had one 6hr period where I have sleep continuously and maybe one or two, four hours sessions.
Continuous sleep for 6 hours straight is actually pretty rare---regardless of whether one is on PAP or not. Many people slightly awaken after every REM cycle and they occur about every 90 minutes. But most people don't remember these post-REM wakes because they are short (less than 5 minutes) and cause no disruption of the overall quality of the sleep.
Some people are much more prone to waking up
completely after many REM cycles and
staying awake long enough to remember the wakes. If the length of the wakes are long enough, the sleep will feel disturbed. The trick here is to try to teach your body to
not freak out when you find yourself awake for no real reason, but to quickly get back to sleep. It's easier said than done for many of us. I've been PAPing for 4 1/2 years, and most of the time I wake up every 1-2 hours enough to turn the machine off and back on to reset my pressures back to the min EPAP/IPAP settings. I think the longest I've ever gone without waking up while on PAP is probably about 3 1/2 hours. But when my sleep is actually
good (and I'm waking up feeling rested and refreshed), I see many more "turn machine off/turn the machine back on" incidents in my nightly data than I remember wakes. In other words, I may feel that I've pretty much sleep for most of the night, but the data still shows I woke up enough to cycle the machine off and back on after almost every presumed REM cycle. The difference between a good night and a bad night is that I don't remember any of the wakes on a good night and I remember 1/3 to 2/3 of the wakes on a bad night even before looking at the data.
These were disturbing events last night. It did happen once before but at that time I was groggy and not very alert. This time I realized exactly what was going on.
It sounds like you are starting to (inadvertently) train your body to come to full alertness when something like this happens. If you can avoid unnecessary worrying about this kind of event, you may be able to return to sleep fast enough where you no longer remember the wakes and then your sleep will feel much better.