Two nights on CPAP- Perception and SleepyHead don't match

Hello,

I posted yesterday for the first time as a guest, so this is only my second post. I am very new to CPAP and even though I have done quite a bit of research prior to receiving my machine I am still struggling to figure out whether or not I'm on the right track.

With the help of some very patient board members I understand my machine a little better, and have been able to download my first two nights into SleepyHead. The results of the data in SleepyHead came as a surprise, since they are (...as I understand them...) very different from how I perceived the two nights.

Night One:

I was using P10 Nasal Pillows. I really like how they felt, and I believe they "sealed" very well, but as soon as I fall asleep I start breathing through my mouth. I woke myself up a couple of times, and my wife woke me up several more. I did not snore the way I used to, but she described my exhaling as "flapping my lips like a horse." My mouth was very dry when I woke up, I went through all the water in the humidifier, and my throat felt slightly swollen and sore. I didn't consider that night much of a success, no big deal, I'm learning. Chin strap is ordered.

Night Two:

Used one of the full masks I was given during my sleep study, I know it's ResMed, I believe it's an F10. Again the "seal" was very good, I could not detect a leak, and I passed the leak test on the machine. With the help of this forum I discovered that the standard ramp up time is not for me, so I changed the time to five minutes and that worked beautifully. It zips right past the low pressures which make breathing difficult for me. My mouth was covered, so I had no concerns there, and I got to sleep fairly quickly. All in all the night went much more smoothly. My wife woke me up once because I was snoring, but otherwise reported that I was quiet. I woke up once because I felt I didn't have enough air, very unpleasant, and my first reaction was that I'm not putting "that thing" back on. However, I knew that was unreasonable and put it back on. Even though I originally was not real excited about cpap in general because I have a tendency to get claustrophobic, I'm surprised at how easy it has been overall. I went back to sleep very quickly, and don't remember waking until morning. I felt this night went much better. Also, with the full face mask attached to my cpap machine, the machine turned itself off after a couple of seconds, something it did not do with nasal pillows.

Now for the interesting part. I fully understand that I know very little about reading the information in Sleepyhead, but the AHI score for night one was better than for night two, how can that be? I would have guessed that night one was a disaster, and night two ok. I also learned that my pressure seems to be fixed at 9, even though I thought the machine was set on Auto.

Night one was AHI 1.52, night two was AHI 5.65.

I have not experienced that I am sleeping less or that I am more rested in the morning, as I have seen reported by other people. Also, I am just as tired during the day. However, even if that never changes, I'm more than happy with the health benefits, and ESPECIALLY with not snoring.

Night one's low AHI might have been low because you were mouth breathing so much the leak was so big the machine threw up it's little arms and said "I give up" When leaks are substantial the machine loses the ability to both sense and record any apnea events that might be happening.
That's why it's important to have some semblance of decent leak management because if the leaks are bad we don't know if a big blank spot with nothing showing up on the software reports is blank because nothing happened (which is possible) or if a bunch of stuff happened but the machine had thrown up it's little arms and gave up and didn't have a clue what was going on.

Oh...sometimes we have markedly different AHIs and nothing is wrong and leaks aren't the issue because sometimes stuff just happens and we have no logical explanation for it. It happens to all of us...even myself. A couple of weeks ago I had one really ugly cluster of OA events during about a hour in the middle of the night...the AHI was 3.5 over 8 hours of sleep so that was a really ugly cluster of around 30 events during that hour. Now my AHI normally runs around 0.5...so 3.5 was a huge step up for me and even more so because it all happened in one hour. I have no idea what happened. Leak was actually well within acceptable limits for a change. This type of stuff I blame on the aliens playing with us..it's as good of a reason as any because we simply don't know what might have happened.

As a newbie you are likely to have a lot happen and show up on the reports that you may or may not be able to find a logical reason for it happening....and widely varying AHI numbers is one of them.
Also remember...your machine doesn't know if you are awake or asleep and often newbies spend a little longer in awake/semi awake state while adjusting to this therapy....and awake/semi awake breathing is much more irregular than asleep breathing.
Often these machines will flag awake/semi awake breathing irregularities by mistake (often CAs/Centrals) because they don't know sleep status...the just measure air flow. So if you are seeing a sizeable number of CAs/Centrals in that AHI from last night....it might be elevated a little simply from awake events getting flagged and they don't count.

That makes a lot of sense, I'm sure that's exactly what happened. There is no way my score is that low with everything that went wrong that first night. Not to mention I still have quite a ways to go before I'm truly comfortable with the machine. I realized that when I first turn on the machine I am artificially breathing much harder than necessary. Several times during the night I would wake up and think the machine is not working because breathing felt so natural, only to lift the mask and discover that it was indeed blowing full force. I'm guessing that in time I will be breathing naturally from the start.

I am a little confused that it shows my pressure as "Fixed" at 9. Isn't one of the main advantages of this machine that it's supposed to adjust pressure automatically?

Yes the auto adjusting mode can be an advantage but if your doctor wrote the RX for 9 cm then that's what the DME had to set it at.
It can always be changed later. Do you know what the pressure was supposed to be on the RX?

Yes, my pressure is set at 9. I checked the sleep study and this is what is says, "I would initiate CPAP at a pressure of 9 and follow-up for clinical response." That explains it.

Last night I snored so much/loudly that I drove my wife out of the room again, that's with the F10 full face mask. I kept checking for leaks, but couldn't detect any. Leak test on the machine was good as well.

I've been looking around a little. It makes sense that the snoring with my mask on has to do with not enough pressure to keep my airway open, so either I wasn't aware that I was breaking the seal on my mask or the pressure set on my machine is not high enough, right? SleepyHead didn't get me any closer to finding an answer since, as Pugsy put it in previous response, my machine probably "just threw up it's hands" because so much was going on! My AHI score was 1.49, clearly not accurate.