Event Experiment

Okay, guys, will this work?I'm thinking about setting my 420E to the lowest pressure as a CPAP. I never got a really good sleep study the first time. Slept only an hour at a time, so I don't think the number of events was correct. I'd really like to know how many events I would have without my APAP? I realize that even the 4 pressure might prevent some, but otherwise do you think this would work?

Janelle,

derek tried this and I think it worked too well, If I recall correctly he got up and switched his machine back mid night because of the adverse effects of the OSA (or in his case OSH) It would be interesting to see how it goes for you though.

Good Luck!

I think your initial thought is correct. 4 might take care of some hypopnea so that reading might be low, but it would give you an idea of how bad you are without treatment. However, I would suggest you do this over a weekend, when you don't need to be clear headed the next day. The day after is going to be like pre-xpap, along with all of its nasty effects.

As long as you don't mind losing a good night's sleep, go for it! For myself, I let the auto do it's thing, and I do my thing, SLEEP!!

I did the same thing a couple of weeks ago and posted it here Home sleep study using REMStar Auto. (click on text). There was quite a lot of discussion... I never got around to doing the split-night study as "Waddle thru the Mire" (or whatever his name is ) suggested.
derek

Janelle, what you mention is feasible. As mentioned above and in other threads, the RemStar Auto is designed to do this for part of a night before automatically kicking into AutoPAP mode ("split night study"). That implies that any AutoPAP can be set at 4 cm while collecting sleep data and accomplish pretty much the same thing that the Remstar Auto endeavors with its split night study mode.

I also agree with what you and a couple others have speculated that 4 cm can slightly skew the data compared to a PSG at 0 cm.

Janelle, that is almost exactly what I did once, not quite a year ago, with my 420E auto. I set the high and low for the same pressure (4). I ran mine on "auto" though, because I wasn't sure if it would record events in cpap mode. Slept almost six hours, recording almost 2,000 "snores" (acoustical vibrations.) I wore my FF mask to be sure there were no mouth air leaks.

When figuring my AHI for that "pressure of 4" night, I decided to add not only the apneas and hypopneas together, I also threw in the "hypopnea with flow limitation". I figured the limited flows would possibly have turned out to be actual hypopneas had there not been at least 4cmwp helping keep the throat open all night.

Came up with an AHI of 7.39, which jived with what I had long thought would probably stick a label of "mild" on my SDB (sleep disordered breathing.) Since I had never felt the extreme fatigue/exhaustion that many others report, and had always been able to function fine through the day and evening, I figured I'd probably land in the mild category, at least in regard to just "AHI" or "RDI".

Of course, the experiment didn't take into account drops in oxygen level or duration of the drops, which is such an important consideration in a real PSG sleep study. The possibility of a low washout rate of C02 using a FF mask at such a low pressure occurred to me too. I thought, "Oh well, that might fit into this experiment ok, since I was probably not getting enough oxygen pre-cpap anyway."

Technically "mild" or not, my lifelong symptoms of horrendous snoring, being slow to get going in the mornings, drowsy driving, and grogginess after naps had cleared up instantly and completely on cpap and autopap.


The fact that the exact same old feeling of groggy/tired/need-a-nap symptoms hit me the morning after the "4" experiment would have convinced me (not that I needed reminding) that I should never, ever spend one sleeping minute without the machine and mask.

I took a nice refreshing nap at my usual 8- 16 range that afternoon.

RG,

That is exactly why I won't try it!

What about adding in the number of central apneas that the 420E detects?

One reason I wanted to do this study, was as I said before because my first sleep study was a joke. Showed an AHI of 3.3, 1.9 on my back and 5.9 on my side (see, I told you I had more events on my side than back!)

During my first nearly 3 weeks on APAP (Resmed Spirit), with 95th precentile pressure 12.4 and median 10.6, I had an AHI of 6.6 This might partly be due to taking mask off and not turning off machine and letting it run until I put it back on. I was also having a lot of repositioning from leaks with the Breeze during this time. (I had been titrated at 8 in the titration sleep study). Interesting, huh? 3.9 AHI on my titration study. My first two week on the 420E showed AHI of 1.2 with average pressure of 7.3. This was before I turned off the IFL. Haven't had pressures nearly that high ever since.

I noticed that one reason my doctor prescribed an APAP, by the way, was because he felt that it would also deal with the snore events. Things that make you go "Hmmmm"

I posted the wrong link above concerning my home sleep study outcome...

Take a look at The Experiment

derek

Janelle, I included the Ca's (centrals) on the experimental night into the total. I had two Ca's on the experimental night. With the 420E operating at normal treatment range I usually had no Ca's, or at most a random one or two on occasional scattered nights.