CPAP better than APAP for me?

[fredr500]

I'm a relative newbie, been on the mask for 2 months. Titration test showed a need to 9cm of pressure, CPAP.

I talked my way into a Resmed S9 Autoset.

Spent the first weeks at 9cm, my AHI was in the 1-3 range and I was sleeping pretty well.

Then the engineer in me kicked in. What does my body really want? How do I know 9 is right? So I switched to APAP, with an 8-11 range. Checking the graphs showed I was spending time at both 8 and 11, so I opened it to 7-13. No more clipping, all the time was spent inside that range, never hitting the limits, so that must be what I need.

AHI moved to 2-4 range, still not bad. But my sleep went downhill. I was waking several times/night for bathroom breaks, wandering the house because I couldn't get back to sleep, being tired all day, etc. You all know the drill. Also, when I awoke I'd feel like I wasn't getting any pressure, I'd have to open m mouth to feel the flow to know it was running.

So last night I went back to a straight 9cm CPAP. I don't remember waking at all, AHI was 1.5, I feel good today.

I know that's a single data point and I will not make any changes for a couple weeks, but it seems strange that CPAP is better for me than APAP.

Anyone else experience this?

[Pugsy]

so I opened it to 7-13

This was the slightly wrong way to go...decreasing the minimum pressure. The minimum pressure is the most critical pressure setting because it sets the tone for the airway in general...if not quite optimal the machine has to always try to be in catch up mode..the main goal is prevention and not trying to fix something that was broke to start with.
Keep the minimum pressure at a good enough level to prevent the collapse of the airway in the first place and then any subsequent events or stragglers that might need a little more pressure are dealt with more effectively and quicker.

You would probably have been better served to keep the minimum up between 8 and 9 and allow a little room on top for the maximum
Also when the minimum does a better job of holding the airway open then the maximum tends to stabilize and not move around as much.

Finally...some people are sensitive to the slight variations in pressure in APAP mode. The variations simply disturb sleep.
Not everyone of course but for some people that disturbance translate into lesser quality of sleep. For people like that then cpap mode or a very, very tight APAP range is a more suitable way to go.

You might take a look at this thread. It's a good example of how the proper minimum stabilizes the maximum pressure.
viewtopic.php?f=1&t=39869&st=0&sk=t&sd=a

[Drowsy Dancer]

Ah, the joys of experimentation! A man after my own heart.

Some people find the fluctuations in pressure that occur during APAP use disturbing to their sleep. it can kick them out of a deeper level of sleep so that sleep is less refreshing, even if they don't wake all the way up.

Our machines track RERAs--respiratory-effort-related arousals. You might call this phenomenon "APAPRA" APAP-related arousals.

Once you set a Respironics machine to APAP mode, even if min and max are set to the same, you collect additional information on flow limitations. Does Resmed track the same info? If so, you might want to keep your machine in APAP mode but with 9 min and max.

Also, I don't know what EPR feels like on Resmed machines, but in my Respironics machine, C-Flex, C-Flex+, and A-Flex all feel a little different, and I like A-Flex the best, so I run my machine now in APAP mode specifically to use that kind of pressure relief.

[Pugsy]

Once you set a Respironics machine to APAP mode, even if min and max are set to the same, you collect additional information on flow limitations. Does Resmed track the same info? If so, you might want to keep your machine in APAP mode but with 9 min and max.

Resmed machines don't collect Flow Limitation data the same way the Respironics machines do. There is no advantage to using APAP mode with minimum equal to maximum with the S9 like there is with the Respironics. Flow limitation data graphs are still offered in CPAP mode on the S9 unlike the Respironics machines which simply don't bother recording Flow limitations at all in cpap mode. That's why I don't bother suggestion APAP minimum to equal maximum to mimic cpap mode for ResMed users.

Like you I prefer AFlex over CFlex on the Respironics...and for that reason if I wanted to mimic cpap mode and still use APAP mode so that I had my AFlex..I would also do the minimum to equal maximum thing because to me AFlex runs circles around CFlex as far as comfort goes.
Fortunately changing pressures have never bothered me and since sometimes I need substantially higher pressures during probably some REM sleep...I just let the machine go where it wants to go. That's why I do well with a wider range but my minimum pressure still has to be optimal or my AHI will show a bunch of clusters. There's a substantial difference between a 9 cm minimum and 10 cm minimum in my case...like a 50% difference in AHI and more importantly..significant clusters at 9 cm minimum.
If pressure variations seemed to disturb the overall quality of my sleep then I would have to make a compromise if I didn't want to let the machine go where it wanted to go. It would have to be an ugly compromise though..I would hate to make it.
Some nights I don't need much more than 11 cm...some nights I see 18 to 20 cm pressure needs. I wouldn't want to use 18 all night just to deal with 30 minutes of stubborn REM events. Glad I don't have to decide.

[SleepingBetty]

What's the difference between A-Flex and C-Flex? The loaner machine I'm using is a Respironics M Series 510 with A-Flex. I'll be getting a 560 with both. The tech said he used C-Flex at the sleep lab. I couldn't tell any difference.

I'm starting to get a little antsy about getting my own machine and getting it set up so I can optimize my sleep! This one is wide open with min at 4 cm and max at 20 cm. That is what the DME is planning to set my new machine at. My "auto trial" had an avg pressure of 8.5 cm over a 2 week period, so he thinks my recommended CPAP setting will probably be 8 cm. My 30-day avg is something like 7.8 cm and 7-day is 8.1 cm, I think. I looked at it on the machine yesterday. That was the first I knew how to find it!

[Pugsy]

What's the difference between A-Flex and C-Flex?

On paper...not much difference
http://aflex.respironics.com/
CFlex link is in the upper right under Flex Family.

In real life..the difference is how it feels and it is so hard to describe because it is based on each individuals own breathing flow. I may breathe totally different from the next person.
For me AFlex is a much smoother transition...pretty much like normal breathing...don't really feel much resistance during exhale...my mind knows the resistance is there but I just don't feel the resistance like I do with CFlex or even with no Flex at all.

When you get your machine there is a demo available for each Flex option and each setting offered.
Just try the different Flex option along with the different settings to find one that FEELS the best to you. That's the one to use and if not available in your preferred mode of operation...well we can sometimes fudge the mode settings to make it work...like making APAP mode work like cpap mode so that AFlex is still available.

[Wulfman...]

I'm a relative newbie, been on the mask for 2 months. Titration test showed a need to 9cm of pressure, CPAP.

I talked my way into a Resmed S9 Autoset.

Spent the first weeks at 9cm, my AHI was in the 1-3 range and I was sleeping pretty well.

Then the engineer in me kicked in. What does my body really want? How do I know 9 is right? So I switched to APAP, with an 8-11 range. Checking the graphs showed I was spending time at both 8 and 11, so I opened it to 7-13. No more clipping, all the time was spent inside that range, never hitting the limits, so that must be what I need.

AHI moved to 2-4 range, still not bad. But my sleep went downhill. I was waking several times/night for bathroom breaks, wandering the house because I couldn't get back to sleep, being tired all day, etc. You all know the drill. Also, when I awoke I'd feel like I wasn't getting any pressure, I'd have to open m mouth to feel the flow to know it was running.

So last night I went back to a straight 9cm CPAP. I don't remember waking at all, AHI was 1.5, I feel good today.

I know that's a single data point and I will not make any changes for a couple weeks, but it seems strange that CPAP is better for me than APAP.

Anyone else experience this?

ABSOLUTELY!!!
What you've described is pretty typical of people who use an APAP in a range of pressures.
When you go into REM or deeper sleep stages, your breathing changes and the machine interprets the flow limitations (and/or snoring) as needing to increase pressures. Those pressure bumps can jolt you out of those much-needed sleep stages and you suffer from that in the following days. Because of the algorithms, APAPs won't respond to apneas if they occur without preceding events (they're called "frank apneas"). When they DO respond to snores and flow limitations, the pressure increases can jolt you out of the sleep stages or completely awake.

I'm all for people HAVING an APAP because they have multiple setting options, but the users need to determine which mode and which settings work best for them.

I did a full week of a range of pressures (10 - 15) back in mid-2006 and couldn't wait for the week to be over. My sleep suffered significantly and I was waking up many times through the night. It also confirmed that my previously self-titrated pressure of 12 cm (in CPAP mode) had been correct after all. I've never really been a "light" sleeper, and could sleep through many things, but I found out that the pressure changes really messed with my sleep.


Den

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[LinkC]

I can get lower AHIs using CPAP @ my 90% pressure, and I used to do that.

I would switch to APAP for a week or so every few months to confirm that nothing had changed. But I noticed my quality of sleep was better during those confirmations (less daytime sleepiness, better concentration, less waking up thru the night, etc.) So now I'm back to a range... 1 below/2 above my 90%.

So, yes, CPAP can be better than APAP for some. But don't get all wrapped up in the numbers. Remember to consider how you feel while chasing that 0 AHI.

[SleepingBetty]

What's the difference between A-Flex and C-Flex?

On paper...not much difference
http://aflex.respironics.com/
CFlex link is in the upper right under Flex Family.

In real life..the difference is how it feels and it is so hard to describe because it is based on each individuals own breathing flow. I may breathe totally different from the next person.
For me AFlex is a much smoother transition...pretty much like normal breathing...don't really feel much resistance during exhale...my mind knows the resistance is there but I just don't feel the resistance like I do with CFlex or even with no Flex at all.

When you get your machine there is a demo available for each Flex option and each setting offered.
Just try the different Flex option along with the different settings to find one that FEELS the best to you. That's the one to use and if not available in your preferred mode of operation...well we can sometimes fudge the mode settings to make it work...like making APAP mode work like cpap mode so that AFlex is still available.

Thanks, Pugsy! I will probably never really understand the difference--well, maybe when I'm not so sleep-deprived--but, I will definitely check out the demo mode. And I am quite sure I will be seeking help in getting everything optimized!

[Pugsy]

I will probably never really understand the difference--well, maybe when I'm not so sleep-deprived-

Don't feel bad. I have read and read this Flex stuff and I still can't make any actual common sense about it.
All I know to tell people is that it "feels" different and for people to try it to see what feels the best.
Higher settings for me tend to make me feel like I am hyperventilating...like setting of 3...but 2 in AFlex makes me feel like my breathing is totally natural..rate and exhale force. Very hard to explain and the reading material doesn't translate well into real life experience.

[SleepingBetty]

Haha! You're probably right, Pugsy! As long as I figure out which setting is right for me, I don't even need to worry about understanding it. I doubt that will stop me from trying, though!