Two months on the hose. Dropped flex. Best scores ever.

[Doze]

After giving it much thought, I committed the often-discouraged act of "changing several variables at once" two nights ago on my APAP. I'd been getting steady numbers averaging just over AHI = 2.0 since the beginning, with a personal-best of maybe 1.5, and most tweaks to my settings were doing nothing noticeably significant. Most recently, I'd been trying to figure out what worked best for me between the various A-Flex, C-Flex and C-Flex+ options. It hadn't really occurred to me until just recently to ditch pressure-relief altogether, because my switch from C-Flex to A-Flex had left my breathing feeling so natural. But sure enough, I stumbled across some posts here that prompted me to do some reflecting on why I might still need what the manufacturer calls a "comfort feature" when my compliance is so high and I have the will to keep it high regardless. Certainly, for patients who might otherwise be non-complaint without pressure relief it's a huge benefit and a welcome option to have. Served me very well for my initial therapy. But now that I'm accustomed to the hose, and there's no chance I'll give it up, is pressure relief still right for me?

After all, I hadn't bothered with the ramp feature since the first few weeks; maybe I didn't need flex anymore and what if that improves things. To read the manufacturer's literature the various flex options are 'no worse and sometimes better', but I read user reports here that called that into question, and I read the manufacturer's own published study data to find that (in my opinion) their general statements about pressure relief might only be defensibly valid when they broadly summarize the majority, but not necessarily all, of the various independent conclusions in their studies (read for yourself to decide).

In any case, I figured I'd at least try no flex at all, and while I was at it, I'd drop my minimum pressure (I'm using APAP currently) since I could see that I was spending most of my night at that minimum. I partially justified the double change by thinking that if I'm dropping the flex from a setting of 2 why not drop my minimum pressure by 2 as well, since I'm spending most of my night at that minimum and can likely afford to try it lower anyway. At best, that should actually leave me exhaling against the same pressure that I previously was, if I still end up spending most of my night at the (new) minimum. And at worst it'll negatively affect my inhale pressure, which of course is the more important of the two, but the auto algorithm should compensate for, and I'll end up exhaling against more pressure than I was, but hopefully manageable to me. These are oversimplifications, yes. But that was my basic thinking. Figured I'd at least try it and see how it goes.

Well, it appears to have worked out fantastically for me so far after two nights. Two nights ago AHI was 0.6 for 8+ hours and last night 0.3 with 7+ hours on the hose. Hopefully this isn't some anomaly and I've found some solid settings to use as my new baseline. More time will tell. But I'm pretty excited about those numbers and how my settings-change gamble seems to have payed off, and wanted to share my apparent success.

[ycartf]

I have three different xPAP machines, and the first one I got and "cut my teeth on" did not have any exhalation relief. So I was accustomed to the resistance on exhalation (never used ramp either). Once I got my other two machines, I tried the C-Flex option (maybe A-Flex? ... it is an APAP) and found that I actually preferred keeping the resistance that I was used to. When explaining to friends what CPAP does, that was the main part I always emphasized anyway - that you had just enough resistance when you exhaled that your airway never got to the completely-relaxed and passive state where it could close/collapse on you. I have had the same experiences you are describing. Sleep well.

[MauraAnderson]

I definitely do better with no exhalation relief at all.

[barry15]

Great thread. I used an Autoset T for 8 years, and one of the things I liked the best about it when I got it was the exhalation relief (compared to my Sullivan V). So, when I got my PR System One recently, I tried both the A-Flex and the C-Flex, figuring that they were the latest versions of exhalation relief, so they must be great. In fact, I found both of them kind of disconcerting (at the minimal level of 1), so I tried it with the flex disabled, after three weeks. I like it better, as far as how it feels. My pressure is lower now (set at 6.5 to 8.5 right now) than when I first was on CPAP, way back when, so that is perhaps part of the story. Anyway, I haven't seen my numbers yet, as I haven't got the software yet, but I will be getting printed data from my doctor's office on Monday or Tuesday, and I will be interested to see what my AHI is doing with no flex.

Thanks for the topic. I never would have guessed that no flex was better than the latest and greatest thing. It is very early days yet for me, with this machine, and I might end up using a flex setting, but it is very interesting to me to hear that at least a few other people do better with no flex at all. It also never occurred to me before that one of the reasons for them to have the flex feature was to help compliance, but that makes sense to me. Like you, compliance is not an issue with me, as I can't fall asleep without my machine any more, and I have used a CPAP machine absolutely every night that I have slept for the last 12 years. I have missed a couple of times because of power outages and because of overnight plane flights, but otherwise, I use it 100%.

Barry

[mipookiebear]

Thanks Doze for the suggestion of dropping the flex feature. I have not tried that. I need to get my AHI down. I will try that myself & see if it helps. I didn't see the other post concerning this.

[Doze]

Glad to hear feedback that other folks have also been doing great with no exhale relief. It's both encouraging and validating, thanks. And I hope it trials well for you too mipookiebear. It's great that while these machines are functioning nightly for us as long-term lifesavers, they can also be tuned like this to try and optimize therapy without much adverse risk.

And for some more good news, since it seems folks are interested. I've got access to the waveform report and one thing I had noticed with exhale relief turned on (to 3 in my case) was a very sharp, very long extended dip or edge to my sharkfin pattern on the bottom side. The waveform looks more like published images of 'ideal' waveforms to me now without flex. I'm not sure if there's any actual correlation or not (search on the forum hasn't turned up much for me on this), but I had suspected that such a huge/sharp delta over such a small time interval might possibly be related to the puzzling excessive Vibratory Snore events I was recording. I'm no fluid dynamics expert by any stretch, but it seemed at least plausible that such sharp changes in airflow could cause 'cavitation' or some similar vibratory effect. My wife was telling me she couldn't hear any more snoring, yet the machine was at times scoring double digits for the VS index for me those first two months. It wasn't consistent; I'd also have nights where the VS index was quite low. But so far these past two nights have both had a nice low VS for me, and I'll be watching that closely going forward too. I've got the impression VS is not something to be overly concerned about, but I can't shake the sense that while I'm trying to optimize most of these other event categories, why not that too!

One correction note I thought I should also mention. I see in another thread today where Rested Gal clarified about EPR vs Flex settings, that I was mistaken above about A-Flex setting 2 being equivalent to 2 cmH20. That's only true for EPR, not Flex, which is more 'flexible' about the actual amount of pressure relief.

[Doze]

I figured that pictures might be far better than my description above, so I'm trying to post them.

Here's 6 minutes with Flex on 3:


And 6 minutes of No Flex at all:

[grandmma]

I agree, turning the C-Flex off made a significant difference in my #s also.

I'm also one who does not prefer APAP. Tried it during trial period prior to purchase, but did far better on straight CPAP so saved myself the extra & went for the CPAP machine.

Funny enough, went into the menu for some reason, and C-Flex appears to be disabled - "X" on screen. Don't know if that's something I've inadvertently set, or a machine malfunction, but either way, don't miss it.

[Doze]

It's been two months now since I turned off Flex (four months overall into therapy) and I thought I'd check in. My average AHI for these past two months is: 1.0

Been feeling great, although I'm not pushing myself as hard as I was at first to make sure I get enough hours of sleep, which is so critical. Had some trouble with the Quattro and leaks for a while, but reading someone's advice about tightening the bottom straps snug and the top straps a bit looser, seemed to bring that back under control.

[DreamDiver]

I have to agree. C-flex sucks. There is something about how at the end of an exhale, where pressure relief ends just microseconds before I've finished my exhale that causes me to attempt to inhale slightly early on each breath. Worse, it happens while I'm asleep - an automatic response to that kind stimulus. For me, the c-flex option just makes my breathing race faster and deeper than it should - like I'm constantly out of breath. After doing that all night, my diaphragm feels like it's had a workout - and not a pleasant workout. It may work for some people. I'm glad it's easy to turn off. My AHI shot down like a bullet when I did.

[rosiefrosie]

I have been on xpap therapy for over 4 years now. My ResMed machine has EPR, which I never used until about 4 weeks ago. Thought I would see if it made any difference. Well it sure did. My leak rate has been lower than ever. My numbers did go up a little for a few days, but then came back down to what they usually run and that's hardly ever over 2 for any of the numbers. Not sure how EPR, C-Flex or A-Flex differ. But the EPR has worked for me and I have it set at 2. Just goes to show that everyone responds differently to treatment and it pays to experiment to find that out.

rosie