Resmed S9 vs Resmed AirSense 10, algo differences?

I've been "on the PAP" for about 9 years. I've been using a Resmed S9 Autoset (based on all the good things I've read about APAPs from this forum.)

Something came up recently: I was "forced" to have an annual appointment with a sleep doctor. (I don't usually see one, because I take it from the standpoint of a mechanic: if it ain't broke, why would I go asking about problems? I mainly self manage my care, but was originally diagnosed by a sleep doctor.) When I told the respiratory therapist I had my machine for 9 years, she said "yep, it could be time for an upgrade". I've been putting off the Resmed Airsense 10 because: 1) Why I already have an APAP 2) Extra cost for what gain? I haven't heard of new features worth upgrading for. 3) "If it ain't broke, don't fix it."

So, I did get myself a brand new Resmed Airsense 10 Autoset, based on the Respiratory Therapist's advice and renewed prescription. Last night was my first night on the new machine. I just downloaded data to SleepyHead, and I'm very confused. I'm still using the same mask. (Resmed Quattro FFM, and I have an F20 AirTouch on it's way to replace it.)

My biggest/only question is: Why did the S9 have me just about maxed out on pressure the entire night, but the Airsense 10 shows the pressure going up and down?
I suppose it's either:
1) Airsense 10 has a better algorithm? (Also: I'm using the regular APAP mode, not the "for her".)
2) Some other Airsense 10 / S9 design improvement?
3) Maybe the S9 had a failing pressure sensor? (Maybe? My S9 shows zero leaks. I thought my mask fit was just great? Or maybe Airsense 10 has a different algorithm there too?)
4) Some even stranger software bug in S9 that maybe only presents itself after lots and lots of usage? (I am a developer, and it bothers me greatly that Resmed can get away with no open source / no changelogs / nothing.)
5) Extra piece of data: Looking back randomly in SleepyHead for July 2015 with my S9 AutoSet, the pressure did go up and down similar to what the AirSense 10 looks like...
6) Further analysis shows that my Tidal Volume on the Airsense 10 is around an average of ~330, but on the S9 it's an average of ~148. Also S9 shows a higher flow limitation than the AirSense 10. Maybe I had a crimped hose or something weird like that?

If I go back about a week looking at the mask pressure / pressure graphs, they all look about as flat, with some minor variances just like the S9 graph attached. (Also: EPR: off on S9, EPR: off on AirSense 10, just confirmed.)

tl;dr: Why did one pressure graph go up and down during the night and the other didn't, with the exact same settings and mask, just a newer machine?

Could have something to do with your leaks. No leaks with S9.From my understanding the S9 and Airsense have very similar algorythms.

This could have been solved if SleepyHead used some Tidal Volume math. (To flash a huge warning saying: 200ml Tidal Volume is really low!)

LSAT wrote: ↑

Fri Apr 12, 2019 5:16 pm

Could have something to do with your leaks. No leaks with S9.From my understanding the S9 and Airsense have very similar algorythms.

I'm very suspicious of that leak line on the s9... I'd suggest the OP go back and check a few different days. A leak line of 0 all night long is very suspicious (even bleep users usually have at least a couple blips).

palerider wrote: ↑

Fri Apr 12, 2019 7:07 pm

LSAT wrote: ↑

Fri Apr 12, 2019 5:16 pm

Could have something to do with your leaks. No leaks with S9.From my understanding the S9 and Airsense have very similar algorythms.

I'm very suspicious of that leak line on the s9... I'd suggest the OP go back and check a few different days. A leak line of 0 all night long is very suspicious (even bleep users usually have at least a couple blips).

@palerider, after (just minutes ago) reading posts about SleepyHead from back in February, it was strange to see your name. (I haven't read the entire thread, just the first few posts.) Sad to see developers have turf battles like this. (Myself being a fellow developer, and having been helped by having SleepyHead to interpret my data.)

Anyhow, I am attaching more data that helps see more of a picture of what's going on with my crazy night-breathing. Unfortunately, it's missing the detailed data to the left of March 10, because I am a slacker (developer!) and only recently started downloading from the card again. (Or maybe the low amount of oxygen at night has sapped my mental strength. *shrug*) Definitely a higher level of Tidal Volume though, which I am quickly becoming an armchair respiratory therapist to be able to understand what that means. (After reading some pubmed and Google searching, (using 95th percentile) 2 ml/kg every night for the past years going to 5 ml/kg in the past week is kind of a crazy change! RT literature seems to recommend 4 ml/kg to 6 ml/kg, at least when awake...)

I just used "for her" mode last night. I'm hoping my body likes the attack at my masculinity in exchange for just a lower drop off of pressure over time. (Weird how Resmed couldn't just say "APAP mode 2, which may or may not help some people".)

Also: I am tempted to send the physical S9 off to one of those repair services. At least maybe they could test the output pressure in a way that I don't have time or tools to test for.

Afterthought: I never would have seen the weird Tidal Volume without SleepyHead.

Any DME can check the output pressure in a minute. In fact...there are posts here that tell how you can do it at home. I don't have time to do the search, you can try.

LSAT wrote: ↑

Mon Apr 15, 2019 8:58 am

Any DME can check the output pressure in a minute. In fact...there are posts here that tell how you can do it at home. I don't have time to do the search, you can try.

CPAPTalk makes me think of DMEs as some sort of demonic people meant to do nothing but charge me tons of money for very little service. (I'm sure it probably makes sense to go to a local DME and have them take a look at my machine. Just pointing out my reluctance, lol.) I guess I will at least have to get some estimates.

Checking your pressure (for free) is one way they can get you in the door.
If they want to charge--ask how much--while putting your coat back on.