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An Experiment in AHI - PaulaO2 - 01-09-2013

The following was a potentially dangerous thing. I admit to being an idiot. I broke a LOT of rules (too many changes in too short a time period, changes were too big, etc etc). DO NOT be an idiot like I am. ApneaBoard does not advocate us being idiots with our health in regards to our sleep apnea treatment.

I love to experiment with stuff.

I was thinking the other day about how low my AHI is (1.27 average). Which got me to thinking how would I know if my sleep apnea "went away"? It won't but that "what if" hung in my head.

So I took my Autoset, put it into CPAP mode and changed the pressure to 12, the setting I had on my Escape. I was surprised that my AHI barely moved. I did this for 2 nights and both nights, the AHI was below 2 (1.4 and 1.82). So I dropped it down to 10 for 2 nights. Again, the AHI barely moved (1.1 and 1.17). Last night I dropped it to 8 for less than an hour. I was told twice in that hour to stop snoring. I finally admitted to experimenting. Which got me in trouble. "Next time you want to be an idiot? Go sleep in your office." (there's a futon in there)

Some things I noticed in my short experiment:

the length of the events were much longer. Instead of the usual 10-12 seconds, they increased to 15-20 seconds. One OA event lasted 25sec. The hypopnea increased in time the most. I had one for 78 seconds (next two highest were 50 and 40);

the flow rate, instead of maintaining a decent width with sporadic narrowing for most of the night, thinned a lot for longer periods of time;

I had less leaks;

in those five nights, I had just ONE central event (I usually have at least 3 a night and as many as 11);

and my snoring must be spectacular! (the snore graph is awesome)

Despite the AHI barely moving, I felt like crap, each day progressively worse. Nodding off during the day, not thinking clearly, and I woke each morning with my heart pounding. I would not be surprised if my blood pressure rose quite a bit.

I know that this experiment is just that, an experiment. Two nights per change is not enough time to notice any trends. I may later go back to the straight twelve for about 2 weeks, just to see if the AHI slowly rises (my bet is it will).

To be more complete an experiment, I should have used the oximeter. My bet on that would be despite the low AHI, my blood saturation would have dropped much further due to the longer hypopneas.

What has this proven? That AHI is but one part of the equation that is sleep apnea. That how you feel is just as important, probably more. Next would be the length of the events.

Going just by the AHI, my pressure could be "safely" put on 10. But going by how I felt and using the elbow test, 14 is the best pressure with 16 being my 95%.


RE: An Experiment in AHI - Sleepster - 01-09-2013

As you know, you changed the pressure by too much and you did it too often. I would bet that your AHI would change in response to these changes in pressure if you had made the changes more slowly.

My prescribed pressure is 13, but it got lowered to 11 and then to 10 by my doctor as I had problems adapting. When I lowered it a bit more my hypopnea index went up, but just a bit. I've slowly tweaked it back up to 11 successfully.

I may try raising it a bit more. I now wait a month or two between changes of just 0.5 in the pressure.

I've got my leaks and my AHI under control, so these small tweaks are just icing on the cake.

I can't really go by how I feel because that varies so much from day to day. I can say that I feel much better than I did a year ago when I started CPAP, and I continue to improve. I'm adapting at a snail's pace.



RE: An Experiment in AHI - zonk - 01-09-2013

(01-09-2013, 07:02 PM)Sleepster Wrote: I'm adapting at a snail's pace.
the turtle always beat the rabbit Dielaughing




RE: An Experiment in AHI - Ugly - 01-09-2013

(01-09-2013, 07:19 PM)zonk Wrote:
(01-09-2013, 07:02 PM)Sleepster Wrote: I'm adapting at a snail's pace.
the turtle always beat the rabbit Dielaughing

Speaking of which....

I had my appointment with my resp therapist today.
She still insists the "experts" thought my CPAP pressure didn't change. I told her the whole sleep study was flawed.
When I borrowed the S8 unit it was the first time I was able to get record of AHI etc. I told her that keeping stats was, to me, vital for my well being.
She was surprised and said that when I was issued the "brick" she felt it was "good enough" for most people and didn't seem to realize that I needed to be more analytical and active in my therapy. I guess I was dismissed as another dummy. She has come to the reluctant realization that yes, I can set the pressure on my machine. She knows I have oodles of reference material.
On a positive note she did give me my ClimateLine hose I was waiting for. And of course, I already had the instruction manual printed out (English only). I told her my experiences and that I talked to ResMed. It seems she has to talk to others in the company before trading up to an S9 AutoSet. But I did get her to admit that if need be I will find a way to pay the difference if we have to go through ResMed. I guess maybe I really do look dumb and she wanted the quickest way to deal with me. When this is over and I have the AutoSet in my hot little hands I will finally be able to tell her - I was disappointed with how she handled my situation and I'm glad there are other vendors in town.




RE: An Experiment in AHI - PaulaO2 - 01-10-2013

(01-09-2013, 07:02 PM)Sleepster Wrote: As you know, you changed the pressure by too much and you did it too often. I would bet that your AHI would change in response to these changes in pressure if you had made the changes more slowly.

I plan on trying it again, this time slower. I think I'll go down to straight 12 for two weeks. If the AHI stays the same (which I don't think it will), then I'll go down to 10 or 11 for two weeks.

I was surprised at how bad I reacted to the 8. For one, it took me a while to get to sleep. I felt smothered by the low air pressure.

Not sure how the Snore index works in SleepyHead but I went back through all of December and I never went over 1. Highest I saw was an .86. But last night I got just under 3.02 then basically flat-lined as usual after I went back to APAP mode.

[Image: snore01.jpg]


RE: An Experiment in AHI - TheWerkz - 01-10-2013

(01-10-2013, 12:11 AM)PaulaO2 Wrote: I was surprised at how bad I reacted to the 8. For one, it took me a while to get to sleep. I felt smothered by the low air pressure.

Not sure how the Snore index works in SleepyHead but I went back through all of December and I never went over 1. Highest I saw was an .86. But last night I got just under 3.02 then basically flat-lined as usual after I went back to APAP mode.

You basically had a sleep study and not CPAP therapy since the pressure wasn't sufficient to keep your airway open, it mostly recorded events as they happened.

The Snore Index is the same in ResScan, I've always wondered how high one could actually get, I've hit 1.0 a few times but I wasn't sure if that was the top-end of the scale or what was, now I'm wondering just how high my SI would be without adequate pressure.Thinking-about




RE: An Experiment in AHI - Shastzi - 01-10-2013

Paula02:
Use the oximeter, Luke! Smile
It would be awesome to post that graph along with the pressure events and see how they corellate!

I am finding out the same thing as you, I think, but I am working on only oximeter ODI events.

As long as the saturation stays above 90% I call it a good night's run.
Of course lots of other things can occur to wake me up but at least it's not lack of oxygen!
Smile




RE: An Experiment in AHI - SuperSleeper - 01-10-2013

(01-10-2013, 11:27 AM)Shastzi Wrote: Use the oximeter, Luke! Smile

Somehow, I knew you would say that, Shastzi. Too-funny Bigwink

Anyhoo.. Paula, I think your experimentation is great, as long as it's taken slowly like you said. It could provide from very useful information to us, for sure!

Sort of like the doctor who develops a vaccine and wants to test it personally first before subjecting the general public to the risks. Thinking-about Bigwink

Hope your willingness to be a guinea pig doesn't negatively affect your health... but I admit, I'm anxiously awaiting any results you post!

Thanks


RE: An Experiment in AHI - HoseHead58 - 01-11-2013

LOL. Paula must be an engineer! Let's collect the data and tweak it to make it even better!
I admit, I am an engineer and because of what I read on this site, I fought the system to get a S9 Auto at the very beginning so that I could make changes later. Good decision. I did tell the doctor that the first month the pressure would stay at the prescribed constant 10. Then I went back for the first follow up and although I was feeling so much better, and the AHI numbers were typically 1-3, I showed him the data (which surprised him that I had data, charts, graphs, etc...) and I talked him into changing to auto mode. I suggested 8-12 but he prescribed 6-14. So I went home and set it to 8-12! LOL! It was over the holidays and it took the DME several days to get the new prescription. They then remotely set the CPAP to 6-14. So for the last 14 days I've been on the 6-14. The AHI typically is still 1-3 although yesterday I did have a 0.25 (but I felt sleepy in the afternoon). The starting pressure of 6 feels a bit weak to me. I guess I got used to have the 10. The new data shows the pressure typically in the 7-9 range with spikes up to 12. No 14's yet. When I was in the 8-12 auto mode, the pressure was in the 9-11 range. Not sure I feel any better or not but it's interesting to look through the data!


RE: An Experiment in AHI - Shastzi - 01-11-2013

I don't like the idea of some doc or tech changing the pressure remotely.


Annoyed-and-disappointed