You may have another horrible night (or not) getting used to a new mask. Can you post up some sleepyhead graphs?
Using FlashAir W-03 SD card in machine. Access through wifi with FlashPAP or Sleep Master utilities.
I wanted to learn Binary so I enrolled in Binary 101. I seemed to have missed the first four courses.
Thanks for the encouraging words, Alan! LOL!!
I'll post some SH graphs tomorrow.
FWIW, I had one or two CAs in my home study (AHI 55.7 untreated). I have probably twice the CAs than other events consistently under xPAP, however. Common sense says no CAs without xPAP and over 50% with xPAP somewhat points to the CAs not being a real issue, especially if the treated AHI is below 5 (mine is well below).
Some of that may be that while you have the mask on, the pressure from the blower is still circulating 02 (certainly at a lower rate than during inhale, or exhale) and that means that your CNS does not sense low 02 simply because it does not get as low as quick between breaths as it would without moving air. Moving air from the blower will increase aveolar respiration to a degree larger than inhaled air that is not moving, because the 02 molecules come in direct contact the aveoli more efficiently when the air is moving. Air that is not moving may be in your lungs, but it it is just sitting there static and not contacting the aveoli, the 02 does not get absorbed efficiently. Many of the sensors that are integral to the feedback loop that tells you its time to take another breath are actually directly in the aorta and other non-lung areas. Bottom line, it can take longer for the feedback loop to tell your system to inhale under those conditions, and longer pauses may be interpreted as CAs, even incorrectly.
But what is important is whether not taking a breath for a few seconds is actually contributing to an 02 sat that is low. If it is, then maybe the CAs are something to look into. But maybe a long pause between breaths is just normal every so often if it does not significantly contribute to a low 02 sat. This is where I would concentrate if I thought my CAs might actually be problematic.
But I have tweaked things to an average AHI of ~1.2 for the last couple of months, so I feel that's an acceptable number. The pressure can actually cause CAs, which is why when under APAP it is important to set a top limit to the range that helps prevent this (generally speaking, you can bring that number down until you start to bump up against that ceiling in most cases). In my case, lowering the top limit might lower CAs even a bit more, but I would indeed be bumping up against it (the APAP would be trying to deliver a higher pressure because it senses that I might need it) and I don't think my pressure limit is so high as to really be contributing to CAs all that much.
CAs are a little scary, because an OSA event is just a physical obstruction that you can fix with pressure, while the xPAP does not really have an effective therapy for CAs (or hypops) and a CA is not an external obstruction that can be dealt with; it is a function of the CNS directly. So it gets your attention. In most cases, however, for common OSA, a raise in CA events is caused by the pressure, and they are actually false positives for the most part.
The thing to really look into is whether your CAs might be something that would warrant a different type of machine, such as an ASV. A good PSG and a sleep doc that will parse that data and tell you yea or nay on that point is probably in order.