I don't get it! AHI still high

[Pugsy]

Take a stroll down this thread with particular attention to what Ozij says at the bottom of Page one.
See if that helps with your questions.
viewtopic.php?f=1&t=37135&st=0&sk=t&sd=a

I have heard that the ResMed machines respond a little quicker to various warning signs but still not in the blink of an eye and still not in response to the apnea event itself...only to event precursors.
I also don't know in what increments it increases withing a certain time frame.
The minimum pressure is still a critical setting even with ResMed machines though.

Robysue discussed the difference in response times quite a while back.
If I can find what she said I will add the link.

Found it. I have never been able to find out exactly in what increments the pressure goes up and how long it takes to get there.
viewtopic.php?f=1&t=79280&p=721818&hili ... se#p721818

[mellocello2003]

Cool. I actually have a special pillow that I use to help me sleep on my side. It's the leachco snoogle - it's intended for use by pregnant women but seems to work relatively well for me. Of course I can't be sure, though. So it's either that or REM sleep potentially causing changes in AHI, or some less likely factors, as you say. REM sleep causing apnea events is interesting. I should read up on that.

I actually figured that the auto pap detected both apnea events and other scenarios, and started to increase pressure gradually until they ceased, then occasionally, dropped the pressure to see if events would not come back, so as to ensure that the user doesn't always end up at the maximum pressure by the end of the night. My point is that if it's beginning to detect events, whether they be actual apnea events or not, there is logically some "knob" in an algorithm such as this to increase the reactivity. I also didn't understand that if its detecting events (as in the provided image) why it doesn't take that as a reason to further increase the pressure (gradually).

But it's all good.

One last question. I take it that some people can never really get to an AHI of 3 or lower with CPAP. For those people, what would be the cause? I'm assuming this is going to be a very difficult question to answer, and one that may need a doctor and a sleep study, but I figured it was worth a shot!

Anyhow, thanks again for all your help.

[mellocello2003]

Looks like I didn't read your latest reply. That's a useful description.

[Wulfman...]

Cool. I actually have a special pillow that I use to help me sleep on my side. It's the leachco snoogle - it's intended for use by pregnant women but seems to work relatively well for me. Of course I can't be sure, though. So it's either that or REM sleep potentially causing changes in AHI, or some less likely factors, as you say. REM sleep causing apnea events is interesting. I should read up on that.

I actually figured that the auto pap detected both apnea events and other scenarios, and started to increase pressure gradually until they ceased, then occasionally, dropped the pressure to see if events would not come back, so as to ensure that the user doesn't always end up at the maximum pressure by the end of the night. My point is that if it's beginning to detect events, whether they be actual apnea events or not, there is logically some "knob" in an algorithm such as this to increase the reactivity. I also didn't understand that if its detecting events (as in the provided image) why it doesn't take that as a reason to further increase the pressure (gradually).

But it's all good.

One last question. I take it that some people can never really get to an AHI of 3 or lower with CPAP. For those people, what would be the cause? I'm assuming this is going to be a very difficult question to answer, and one that may need a doctor and a sleep study, but I figured it was worth a shot!

Anyhow, thanks again for all your help.

Tweaking one's pressures makes it easier to get lower AHI. Switching to CPAP (single pressure) can achieve lower AHIs and better sleep quality. That's because in APAP mode, the events occur before the machine can react and therefore increase the AHI numbers.
From looking at your reports, your pressure settings aren't optimal. You're also one who has a number of "frank" apneas (ones without preceding snores or flow limitations). Increases in minimum pressure or switching to straight-pressure CPAP will help get your numbers lower.

Also, in my opinion, many of those people who can't seem to achieve AVERAGE AHIs of less than 3 (and who don't have complicated situations) don't have optimal therapy settings. Don't get me wrong, numbers in the "3" range aren't bad, but I think many could do better if they would tweak their settings. The numbers aren't everything, either. The "how you feel" factor is a much bigger deal in my opinion.


Den

.

[mellocello2003]

Hey Den, thanks for the response. That's very interesting. So, when I up'd the pressure a few days ago by a bit and my AHI spiked - that's high-frequency noise that will settle once I've adjusted to higher pressures? I'm interested in trying to your suggested approach of switching to straight CPAP and upping the pressure, but I was wondering if you could give me a game plan? Increase the pressure by 1 and go to CPAP mode? Presumably feel like crap the first few days, but monitor and tweak as needed?

Thanks again in advance

[~Q~]

Just a comment/observation:

I notice that your sleephead report says you are running A-Flex. When my doctor originally set me up with my xPAP, she told me that C-Flex gives you more "aggressive" therapy than with A-Flex. A-flex is really a comfort setting that she only liked to use if you were having a hard time tolerating the xPAP machine. I am not well versed in xPAP technology, but it sounded to me like A-Flex gave the Autopap machine some Bi-Pap type functionality.

Perhaps you might benefit from shutting off A-Flex and running with just C-Flex. C-Flex decreases pressure by a set amount when you exhale.

Maybe one of the pro in there like Pugsy knows a little more about this than I do and can explain it better.

[Pugsy]

AFlex and C Flex don't either one reduce the presser by any fix amount.. They reduce it based on the patient's force of breathing. Nothing in any of them feels like or comes close to the a huge drop immediately in exhale

Read about here
http://aflex.respironics.com/

C Flex is not designed to be aggressive...none of them are.

[Wulfman...]

Just a comment/observation:

I notice that your sleephead report says you are running A-Flex. When my doctor originally set me up with my xPAP, she told me that C-Flex gives you more "aggressive" therapy than with A-Flex. A-flex is really a comfort setting that she only liked to use if you were having a hard time tolerating the xPAP machine. I am not well versed in xPAP technology, but it sounded to me like A-Flex gave the Autopap machine some Bi-Pap type functionality.

Perhaps you might benefit from shutting off A-Flex and running with just C-Flex. C-Flex decreases pressure by a set amount when you exhale.

Maybe one of the pro in there like Pugsy knows a little more about this than I do and can explain it better.

No, you're confusing ResMed's EPR exhale relief with Respironics'. C-Flex (and A-Flex) decrease pressure relative to the exhalation effort......not by a set amount......EPR drops pressure by a set amount.
Your doctor's knowledge is "questionable".
All of the "Flex" technology is pretty well explained on Philips' website.

However, many people who have experimented with the Flex options end up liking one over the other or even turned off.

PS. I see Pugsy was posting the same thing as I was typing......so, I hated to delete what I had written and am reinforcing what she had said.

Den

.

[Wulfman...]

Hey Den, thanks for the response. That's very interesting. So, when I up'd the pressure a few days ago by a bit and my AHI spiked - that's high-frequency noise that will settle once I've adjusted to higher pressures? I'm interested in trying to your suggested approach of switching to straight CPAP and upping the pressure, but I was wondering if you could give me a game plan? Increase the pressure by 1 and go to CPAP mode? Presumably feel like crap the first few days, but monitor and tweak as needed?

Thanks again in advance

Since your minimum pressure is already at 10 cm., I would suggest starting with single pressure at that pressure for a few nights at a time (minimum of three to five). Analyze the reports and see if an increase is necessary. If necessary, move up one centimeter for a number of nights and reanalyze.
Set your minimum pressure and maximum pressure to the same setting so you'll be able to see Flow Limitations.
By the way, you don't seem to have many flow limitations.
What the objective should be is to eliminate as many variables as possible. And, running in a range of pressures introduces many variables.......varying pressures, leaks, subconscious reflex responses to pressure changes, complete awakenings, etc., etc.

Den

.

[mellocello2003]

OK. Trying to process through this and come up with a plan of attack.

I have three tuning options available to me now. Let me know your votes. Also, any other ideas would be greatly appreciated.
- Eliminate the Flex mechanism
- Disable "auto" mode and use a straight CPAP. Note that my current minimum pressure is set to 9.
- Do both

Here are last night's and the night's before sleep captures. I don't feel so great...

[mellocello2003]

My current vote is to do straight CPAP and A-Flex (1) at 10cm.

[Wulfman...]

My current vote is to do straight CPAP and A-Flex (1) at 10cm.

+1 (or you could try C-Flex at a setting of 1 or 2)

Notice in the reports that your apnea events are higher when your pressures ramp up and are fewer when your pressures are lower. Switching to straight pressure makes the machine stop responding to snores and flow limitations......which should improve the quality of your sleep.


Den

.

[Pugsy]

My current vote is to do straight CPAP and A-Flex (1) at 10cm.

Flex (whatever setting) is not the issue...use what feels the best to you and if that is 1..use 1.

CPAP mode at 10 is unlikely to be quite enough but give it a shot.

With CPAP mode you lose FL flags and will get 0.0 showing...it won't be 0.0 for real because CPAP mode simply doesn't gather that data point. Probably not a critical issue but just wanted you to be aware of it. Your FL numbers aren't huge anyway.
You don't get AFlex type of relief in cpap mode...you get CFlex and while not hugely different...it is different.

An alternate way of keeping FL flags and still using pressures that mimic cpap mode is to simply set in APAP mode the minimum and maximum to 10 cm if that is what you want to try. Pressure will be fixed at 10 cm..you get to keep AFlex setting of your choice. APAP mode with minimum at 10 and maximum at 10...it will do it.

There's more than one way to skin a cat.

[Wulfman...]

Definitely more than one way to skin a cat.
It's just that any way is not enjoyable for the cat......


Den

.

[mellocello2003]

Yeah, was looking at the flex options for CPAP mode and noticed that there was C-Flex and C-Flex+. C-Flex+ appears to be the CPAP-mode equivalent of A-Flex. Lovely.

So based on feedback, it sounds like what I'll try is auto mode fixed at 11, and will stick with A-Flex set at 1.

Thoughts?