Can this AHI be correct?

So I've been having a hard time finding a mask I can sleep with since starting with my AutoSense for Her Jan 16. The one I keep going back to is the Nuance Pro, which I have trouble keeping on my head (back strap slips up on the back...hair too slippery). But very low leak rate and much less discomfort on my nasal bridge and pretty much none on my nostrils compared to any other nasal pillows I've tried.

Anyway, the last few nights, my AHI has not been great, 7.37 and 3.25. But last night, for my nighttime sleep (I tried to take a nap during the afternoon), I had NO events! Can that possibly be correct? I'm attaching all three charts.

I still wake up multiple times per night and have difficulty getting back to sleep, hence the attempt to nap yesterday.

Also, I don't really understand how Flow Limitation relates to the other graphs, since it seems to be high and all over the place. Is that something I should be trying to address as well? Thanks for any help.

Last nightTues nightMon night

I have the same machine and mask... did you do anything different at all when you got the low AHI? Sleep in a different position? Was your hair different? Anything that might account for the change? Even things that have no apparent connection to CPAP?

and yes - while I don't know how to interpret SH data the way others can - it is possible to have no events. I have no idea if that's what happened with you - but it is possible

No, I don't think I did anything differently, but it was great to see a low number this morning. Hopefully it will be low again tomorrow morning! And maybe I will even sleep tonight--skipped the nap!

It is common to have different AHI values every night. Your flow limits are all over the place. High flow limits will cause your pressure go up. Your minimum pressure (8 cm) is too low. I would try raising it to 11 or 12. This may be too large of a change to do in one step. If it is too much of a change, make smaller change increments (1 cm at a time).

OK, I will try raising the minimum pressure to 10 and EPR to 3 tonight and see how I do. I have also been having trouble with rainout, so I made a cozy for the short hose which is not heated. I am hoping that will help.

I will post results tomorrow.

booksfan wrote: ↑

Thu Feb 15, 2018 6:56 pm

OK, I will try raising the minimum pressure to 10 and EPR to 3 tonight and see how I do. I have also been having trouble with rainout, so I made a cozy for the short hose which is not heated. I am hoping that will help.

I will post results tomorrow.

Your pressure needs vary based on many factors including position and REM.
Do the above for a week. Your AHI will likely improve.
Then you need to increase your minimum even more. A minimum of 13 and a maximum of 20 is closer to where your needs are.

Regarding rainout, turn the humidifier down or keep the hose warmer. When the humidity condenses, it is not making into your breathing so there is no point in keeping the setting so high. Rainout means the setting is too high for the system to effectively deliver - improve delivery or turn it down.

OK, so zero events was a mistake. Resetting the machine "fixed" it.

I didn't get much sleep last night, pretty much as usual. Awake (at the very least!) ~12:30-1245, ~1:35-2:00, ~2:30-3:00, ~4:00-6:00. Longest period asleep was probably about 1-1/2 hours. Total sleep time, MAYBE 4 hours? Possibly just a bit more since I tried to sleep a little once I took off my mask. That is pretty typical of my sleep pattern for the last as long as I can remember. I don't know when I last slept more than a couple of hours at a time <sigh>. Nights are endless!

The increased pressure was a little difficult at the beginning. It felt kind of like a reverse balloon--I was being blown up! My nasal passages felt like they were expanding and every few minutes a puff of air would work its way out of my mouth. But during the night, no problems. Hopefully no more issues tonight.

I've noticed a few things that lower my AHI... and this is just personal... huge YMMV sticker.
Alcohol (more on this later)
Gaba (probably why the alcohol lowers it)
Ashwaganda (also related to gaba)
Sex (probably related to oxytocin which is a huge anti-inflammatory)

booksfan wrote: ↑

Fri Feb 16, 2018 10:20 am

OK, so zero events was a mistake. Resetting the machine "fixed" it.

What do you mean?
The figure you showed was in error? Did sleepyhead misrepresent the data?
Resetting which machine - the PAP or the computer?

I'm sorry I was less than clear. I reset the machine, by unplugging it for 10 seconds, then plugging it back in. I have since had night with events, which seems more reasonable.

In fact, Friday night was particularly bad. I only slept for about 2-1/2 hours (an hour, awake for a while, then slept another hour and a half, woke and couldn't sleep again). Did you know you can't cry wearing a CPAP mask? I was VERY discouraged! I did eventually put the mask on again for a little while and dozed. Last night was much better! I did still have multiple wakings, but they seemed shorter lived than usual. I am still having trouble with the back strap of the mask slipping and now the pillows need adjusting a lot more, so every time I turn over (I am a restless stomach/side sleeper), that wakes me even more. But I am in a much more positive frame of mind today!

Thanks for clarifying.
Last night's data looks better.
I think you understand your challenges (mask, movement, pressure). Ideally you would be comfortable with your mask, body movement would not disturb the seal, and you would be at enough pressure to minimize your OSA. Getting to this goal can be difficult. In my opinion, time and effort helps us figure how best to adjust the mask. We also learn to be less bothered by small mask leaks. I also think that we train ourselves to move less since that can disturb the seal. The cluster of OA on Friday at 2AM was likely the reason you awoke shortly after. More pressure will be needed to avoid those clusters and keep you sleeping soundly. Unfortunately, more pressure often exacerbates mask issues.

Remember that your cpap data shows events that have not been prevented. You don't know how many events the cpap prevented. You could have an AHI of 0, but have had some number of events that were prevented by your cpap machine. So looking at an AHI of 0 or a very low number is a misleading indicator of how many events you really had.