ASV curiosity

[greenall]

I took it upon myself a few weeks ago to switch myself from a straight cpap at 16, to an ASV machine as I was starting to feel tired again, and couldn't seem to get any consistency in my AHI scores. I have severe apnea (my untreated score was around 59) My cpap scores weren't really bad, but some nights they would be high, and other nights low. I spent tonight going over and comparing the two years of sleepyhead stats I had on the cpap against the ASV and over the last 3 weeks and found some items I really found interesting. Yes, I admit it, I'm a bit of a numbers nut.

• AHI went from an average of about 3.5 down to a 0.2. I've even had a few 0.0's in there since the change

• Leaks now are basically 0. Less pressure, no leaks. Gotta love that.

• Total time in apnea before was about 5 minutes. Now its down to less than a minute. Even better, I'm down to only about 2 or 3 events total a night.

• Now for what I feel is the most interesting one, that I have a bit of a hard time explaining. My min respiration rate is basically unchanged at about 14. The part that I find really interesting is the peak and 95th. The 95th is much lower on the ASV. (16 compared to 22)and the peaks are massively lower. On the cpap, I would peak every night at around 50. On the ASV, the peaks are in the mid 20's. Never anywhere near the high of 50 as before. I have a SPO2 monitor that I used before and after the ASV machine, and basically no difference there (90-95 before and after) , so that doesn't explain the respiration change.

So, I know i've got it pretty dialed in now, but that dramatic peak in the respiration rate has me intrigued.

[Pugsy]

I would need to see the actual breath by breath flow rate for that 50 respiration rate to be sure but I suspect SH was probably double counting a little blip in the flow rate as an extra breath.
When people have reported high respiration rate in the paste we go look at it zoomed way in and in reality it has been about half that high rate. Sometimes little blips in breathing pattern confuse SH and it double counts the respiration rate.

I suspect that using the ASV smoothed out your breathing so no more of those little blips to confuse SH.

[greenall]

okay. I went back to October 3rd and pulled a slightly worse than average night. I've grabbed a shot of the entire night, and then focused on one area where it went high twice.

[Pugsy]

You didn't zoom in enough. Need to be able to clearly see the 1 second lines to count the respirations.

Like this if not a little bit closer. Need to be able to see each 1 second hash mark and the shape of the breath.

[greenall]

Here you go.. a couple even closer.

[greenall]

In case that was too far..

[palerider]

Sh has a bug where it wants to count every zero crossing as a breath, even if they're not breaths...

you have to count a minutes worth of actual breaths to see what the true RR is.

That said, ASVs have a wonderful tendency to normalize breathing.

[greenall]

yeah, you can really see that in the last couple I posted. Where they aren't really breaths and it is just kind of slightly passing above/below 0 quickly.

Agreed looking at the graphs with the ASV, you just don't see that. the ASV really does an amazing job of smoothing out the breathing patterns. Wish I had changed to one earlier!