Has my Resmed gone insane?

Lately my AHI readings have been very high. Like 11 - 16. Used to be fairly good, under 5 quite often.
Last night's AHI read out at 22.8!!!!!!!
Worst night I've ever seen. Although I felt fine.
My PulseOx though showed the BEST night I've ever had. Only below 90% about 18% of the time. Had a baseline of 92.8 I think it was ... highest ever for me.

How can I get such diametrically opposed readings?

A few days ago I bumped the machine up to 11 cm pressure with 3 epr and it felt really good. I wake up feeling pretty good.
But, ever since I experimented with the Respironics machine that someone had doctored up that I got from the auction site my numbers have been higher than they used to be.
I returned to the Resmed Elite S8 hoping my numbers would be like they used to be but they weren't.
But they have never been as high as the software showed last night.
It's like the machine went nutso. It showed some apneas lasting 34 seconds but only one time did that coincide with a blip on the oximeter.
34 seconds should wake me up gasping for air.

It was showing clusters of many many apneas every 45 minutes or so, but the oximeter readings were really nice. Only a couple of blips.

Is there any easy way to test a machine or calibrate it?

I don't think your machine has gone insane. It is just reporting changing conditions.

I have noticed that if I go to bed really beat and tired, perhaps from working really hard outside, that my AHI rises significantly. I also notice I often feel great the next day. What I think is happening is I am sleeping a lot deeper than normal, and that is bringing on more apneas from being more relaxed (I am normally a light sleeper). You may be experiencing the same thing.

Other things you say also suggest you are seeing other changes in your therapy as well. Maybe something is changing the machine as it is currently set up cannot compensate for.

Willie,

Is it normal for you to be below 90% spO2 18% of the time, or is that a typo?

If you are at 11 cm with EPR at 3, you bascially are fighting those apneas with only 8 cm of pressure. Is that enough for you?

jeff

jnk wrote:Willie,

Is it normal for you to be below 90% spO2 18% of the time, or is that a typo?

If you are at 11 cm with EPR at 3, you bascially are fighting those apneas with only 8 cm of pressure. Is that enough for you?

jeff

======================
Yep that was a typo should have read 95% spo2.

I always have a high figure for below 95% ... last night was 78.7% of the time below 95% and that is relatively good. The 18% the other night was wildly above normal. I'm often below 95% saturation over 85% of the time. Fortunately I stay above 90% most of the time. I do drop below 90% for fairly brief periods. Most nights less than a minute or two.

Then last night my AHI popped back to 9.3 ( which is still bad but more in the range it has been lately ). But the apnea index was 3.9 which is probably the most relevant.
Since I bumped the pressure up and increased the EPR to 3 I've been feeling much better. My prescribed pressure over 3 years ago was 9 but I soon figured out that was too low.

I possibly need to have another study done ... only next time I will take my own mask. Seems I have an appointment coming up ... have to search my calendar and see.

But it still puzzles me how I could get such wildly different readings from the Resmed and the oximeter the other night. Way way high AHI and exceptionally good O2 sats. With that high of an AHI my O2 should have been terrible.

Oh well, that's life as a hose head

Arizona-Willie wrote:My prescribed pressure over 3 years ago was 9

jnk wrote:If you are at 11 cm with EPR at 3, you bascially are fighting those apneas with only 8 cm of pressure. Is that enough for you?

ResMed EPR lowers the pressure for the entire exhale, and an EPR or 3 roughly equals a drop of 3 cm H2O. So my opinion is that if you are going to use an EPR of 3 on a ResMed, you need to set your pressure at 12 cm H2O in order for treatment pressure to be at 9 cm H2O upon expiration, when most obstructive apneas are likely to occur.

Willie, Apnea is not a "predictable" condition. Most of us have gone through sleep studies, and were titrated at a specific pressure at a given moment in time--one night. Frequently, those sleep studies were flawed, as it isn't easy to sleep when one is hooked up to multiple sensors, and not in one's own bed. Thus, your actual treatment pressure can vary wildly from one night to another. Moreover, many folks are "position sensitive" in having Apnea episodes--a lot of folks are only symptomatic while on their back.

Additional questions to consider: Are you under added stress? Have you consumed alcohol before going to bed? Do you have any sort of caffeine or other stimulants? Do you take any sedatives? While monitoring the course of my treatment for over 10 years, my pressure has varied widely--sometimes, it is consistent at 7-7.5 CMH2O. Occasionally, I get spikes on given nights, but they are sporadic. So, variability is the name of the game in Cpap therapy. Keep asking the right questions of yourself, and experiment with different pressures so as to get the one that works best for you.

I think (not sure if I remember correctly) that you may have central apnea when you have too much O2, and too little CO2.

However, how you feel is more importatn.

I had pressure too high, and more apneas, and more time spent in higher SPO2 regions -- but I felt miserable, and didtn's sleep well either.

O.

The last couple of nights the Resmed has recorded more normal numbers but it still showing me things that don't make a lot of sense.

Last night it says I had a huge cluster of apneas but my O2 sat actually WENT UP and there was no corresponding pulse increase as there normally is when the O2 sat drops down far enough to disturb sleep.

Then later in the night there were O2 desats and pulse increases but the machine showed only a mild hypopnea. Only about 4 am do both machines show corresponding events.

One of them must be nuts.

Az-W,
This may be a tad off topic but as I live down the road from you I thought that I would tell you what I have observed over the last number of days.
As we just recently had a major change in our weather, the windows are now open and the A/C is finally off. But the first few days I had some problems. On the first night, I awoke to find that I had taken my mask off in my sleep. I haven't done that for months. I was also more congested. Nights two and three had my AHI running in the 7-9 range where I had been running 2-4. My wife (not a CPAPer) mentioned that she to was having more problems than normal sleeping. Seems to be getting slowly better.

I don't have an oximeter so I can't comment on the disconnect in the numbers that you are seeing but I just thought that I'd tell you what I am experiencing.

Hope you can solve your puzzle.

-Clark

We keep the windows closed and have a HEPA air cleaner running in the bedroom 24/7.
It is nice that the heat pump is inactive during the night now.

I never take my mask off in my sleep. I've got the Quattro so it is working very well and is nice and comfortable.

Opening the windows and exposing yourself to Phoenix's polluted air is something I wouldn't consider a good idea.

Many people can't wait for this time of year to open the windows though.

Don't seem to have a congestion problem. My only allergies are : work, bullets, hand grenades, nuclear weapons, and marriage.

Snorebert wrote:Az-W,
This may be a tad off topic but as I live down the road from you I thought that I would tell you what I have observed over the last number of days.
As we just recently had a major change in our weather, the windows are now open and the A/C is finally off. But the first few days I had some problems. On the first night, I awoke to find that I had taken my mask off in my sleep. I haven't done that for months. I was also more congested. Nights two and three had my AHI running in the 7-9 range where I had been running 2-4. My wife (not a CPAPer) mentioned that she to was having more problems than normal sleeping. Seems to be getting slowly better.

I don't have an oximeter so I can't comment on the disconnect in the numbers that you are seeing but I just thought that I'd tell you what I am experiencing.

Hope you can solve your puzzle.

-Clark

I wonder, based on ozij's insightful comments, if it might have happened this way . . .

Maybe you were sleeping along with your EPR on 3 and your pressure set at 11 (basically what amounts to 11/8 bilevel) when some obstructive events occurred (because 8 cm may be too low to prevent them), which, in turn, caused the machine to suspend EPR, putting you at a constant 11 cm (which may be too high for you). Maybe that sudden constant pressure was enough to trigger a bunch of pressure-related central events that neither awakened you nor desaturated you.

That is only a guess, of course, based on the scant evidence at hand. But IF that is the case, running the machine that way may not be the best for you. How do you do at a straight 9 cm with no EPR?

jeff

ps- Is your list of allergies in descending or ascending order?

Another thought I had is if you are having a series of apneic events, perhaps you are aroused enough for your body to respond, but not enough to wake you. Upon arousal, you are breathing deeper or more, and as a result your SpO2 is increasing. But I seem to remember that the arousals would be triggered by low SpO2 and not by some other mechanism. This is something I would ask your doctor about because it seems a bit unusual.

Although the central apnea idea somebody mentioned seems a little iffy to me based on your data, I would ask your doctor about that, too.