I got my new CPAP fired up last night, it's the first one I've had with SD capability since I started on therapy around a dozen years ago.
As the SH manual says, there is way more info than can be made sense of right away.
Some of the info is familiar - AHI numbers.
What are the more important graphs to look at?
I was surprised to see snore data. There was a point last night for about 30 minutes where I showed snoring, it also corresponded with a mask leak. The leak wasn't large enough to trigger a 'large leak' reading, but must have been enough to let me snore but not trigger any hypopneas.
The other thing I noticed were several points where it looked like I would take a very deep breath - breathing rate slowed way down, time of inhale/exhale was long, volumes went up, and one or two other indicators.
There were some other indications of when I woke up or stirred during the night. We had some heavy thunderstorms blast through overnight and I was able to see from the graphs when the noise woke me up either partially or completely.
(07-12-2016, 08:38 PM)KSMatthew Wrote: .......................
What are the more important graphs to look at?
Hi. A lot of folks feel it's flow rate, pressure, leak, and snore (but see below). Those are probably the most important in zeroing in on a good therapeutic pressure range. I personally like to examine all of them (except possibly the cumulative AHI, in which I don't see much value). It's sorta fun to check how some channels correlate with each other - as you've begun doing by comparing respiration rate with volume channels. What I find particularly of interest is to scroll a three-minute window along the flow channel. I try to learn what my sleep vs. awake patterns look like, and whether certain disturbance patterns correlate with apnea events. I'd like to get a handle on the degree to which "sleep wake junk" is contributing to my AHI.
Quote:I was surprised to see snore data. There was a point last night for about 30 minutes where I showed snoring, it also corresponded with a mask leak. The leak wasn't large enough to trigger a 'large leak' reading, but must have been enough to let me snore but not trigger any hypopneas..............
I've seen threads where folks claim that the leak itself causes the snore flags. I believe it from my own experience. The leak transmits a signal down to the flow (and pressure?) sensors, which simulates the same pattern transmitted by an actual snore.
Have fun with SleepyHead. Better yet, feel better.
Oh, and when you get bored with the regular channels, there's always the user-defined functions.
We are such stuff
As dreams are made on, and our little life
Is rounded with a sleep.
Last night was a little rough. I was really beat from the weekend, I worked out pretty hard after work, and my sinuses were acting up a little from the recent rain and pollen it brought. I felt like I had a restless night. My AHI score was something like 2.4 when it normally 1-1.5. The final numbers off my previous CPAP showed my last 7-day average around 2.4 and 30, 60, 90-day average around 1.4.
Yeah, I can see how a leak could generate some feedback the system would read as something else.
There are endless hours of distraction in staring at those graphs and trying to understand what they mean. I finally, suddenly grasped what the Flow Rate and Tidal Volume indicate when viewed together.
07-13-2016, 09:25 AM
(This post was last modified: 07-13-2016, 09:26 AM by KSMatthew.)
I suppose a guy could look at all that data until he fell asleep...
Day 2 on the new machine and my AHI is worse than on day 1. Normal average is about 1.5, day 1 was 2.5 and last night was 7(!).
I know I'm having some pollen reaction the last week and it's causing some issues - maybe I'll try a Benadryl tonight and see what happens. The 30, 60, 90 day values from my old machine were really good, but the 7-day average was creeping up, so I know that whatever's happening has been recent and probably due to some changing weather conditions and the yard work I've been having to do.
I'm using the same settings and the same mask, but a different brand (Respironics now vs Devilbiss). Do they calculate the AHI any differently? Is one more sensitive than the other?
You're going to have good days and bad days, no biggie. I've noticed that my event type and frequency can depend on my physical exertion, or lack thereof, from the my day's activity. The main thing is how you feel.
As far as the difference in event reporting between the two machines, I don't know. Event definitions seem to be fairly well defined between manufactures. The way that each one addresses an event in auto mode is where the "magic" comes into play. Changing machines is probably akin to sleeping in a different bed. . . not bad, but just different enough to effect your sleep quality.
Yeah, I know there are slight differences just because they "sound" different. A day or two here and there isn't a problem. I've been on CPAP around 12 years now, and know what to expect.
Because I have the new recording capability I'm paying much more attention. In the past, I might have looked at my AHI numbers once or twice a year, not every day.
2nd day of data: Interesting differences.
As noted in post #5, my AHI numbers were higher than normal. I felt puny all day, I'm not sure how much is sleep related, and how much is from pollen or whatever else has been causing low-grade sinus inflammation that's giving me a headache.
I looked at my graph. Yeah, I had a high AHI count, but almost all were in the first 30 minutes. After that, I leveled out and if I throw out those first 30 minutes I was probably right down to my normal average. Also, my snore numbers were very high during that same period, then dropped down to almost nothing the rest of the night.
So, it looks like the first 30 minutes of sleep last night were not restful, based on those graphs. Around 2am I had approx 30 minutes of mask leak, but nothing else looked like it was affected by that leak.
I also got a report of "Periodic Breathing = 4.56%" Night #1 did not show any. What does it really mean? Is there a way to see this on a chart?
The DreamStation scores me for PB sometimes too. You can zoom in on the Flow Rate graph until you can see the individual breaths. I do often have a waxing and waning pattern to my breathing. I don't think it is anything to be concerned about until they are separated by apneas. That could be Cheyne Stokes respiration and is associated with heart disease (I think).
Day 3 - AHI is still climbing. Can't figure it out. I'm on fixed pressure, same as before the new machine. What has changed: I put away the older 22mm hose and am using the new 15mm hose. On my Swift FX I alternate between medium and small pillows, I did make a switch to the medium on day 2 and since then I've seen AHI numbers increase. Will go back to the small - I used small on day one and AHI was low.
I haven't looked at the latest detailed report yet, but if it shows what I've seen the last couple of reports, there will be a lot of AHI events in the first 30 minutes, then tapering off to very low, but the average has been driven up. Periodic breathing was showing at 1%, down from from 4.5% day 2 (and zero day 1).
Question: using the wrong size nasal pillows can cause them to collapse and not freely transmit air pressure. What effect would that have? I can see that you'd get a lower therapy pressure to your lungs, but how will the machine and its recording react to what's really an obstructed circuit vs an obstructed airway?