30 yr Male Just Diagnosed w/ Severe OSA

[Dormeo]

ReturnofXil, thanks for the questions and congratulations on your results! Sleeprider, thanks for the answers!

[ReturnofXile]

The more appropriate metric to watch is minute vent (L/min), which is the product of tidal volume (mL) and respiratory rate (BPM). So you are correct that the respiratory rate needs to be taken into account.  In your case, we only increased EPR by 1-cmH2O, so the changes were not very dramatic but you "felt" the difference, and it was sufficient to overcome most of the residual upper airway resistance and flow limitation. To get to the next level, you need a true bilevel which is not limited to pressure support of 3-cm.  Your results are outstanding and we were only tweaking the settings to optimize them. I would not waste my time or money on an oximeter in your case.

Thank you Sleeprider for explaining all of that. So I guess my next question would it be worth to get a ResMed Aircurve 10 Vauto bilevel machine? Right now, I'm still under the 30 day money back guarantee. I looked at the prices online and it seemed that the bilevel machine was about $500 more expensive. My wife and I are quite frugal so money isn't really an issue. I'd most likely just buy from cpapshop.com or something like that. But would it really make that much of a difference? 

It is my understanding according to the charts I uploaded, that 95% of the night my flow limit was below .01, which at first glance doesn't seem to be a concern. However, if you look at the flow limit chart (I attached it), it kind of seems like the flow limitations happen in clusters, which seems like it could have an effect on sleep quality. My first thought was maybe it had something to do with REM sleep or if it was some type of positional apnea. With the chart that I uploaded, I tried to look for factors that correlated with the flow limit.  It seems like there's a somewhat correlation between flow limit and leak rate, but that could just simply be the machine increasing the pressure at it's detecting a flow limit and then the mask starts leaking more because of the increased pressure. 

Lastly, could it be said that flow limit might only be a problem if they actually lead to RERA's and hypopneas? In my case, it doesn't seem like they are leading to arousals. One of the sleep technicians I saw on YouTube said if they the events don't lead to an arousal, then it's probably fine and won't impact your sleep.  I scrolled through my data and didn't immediately notice any arousals from flow limits. Very curious to know what you think. 

Thank you and have a nice day.

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Whoops, I forgot to attach the expanded view of flow rate and flow limitations.

[ReturnofXile]

Hey everyone! Tt's been about almost two weeks since I've started therapy and for the most part things are going good. I've straightened my mask issues (so now my average leak rate is around 2.5 liters per min), and overall, I'm getting used to the therapy. The one thing I've noticed is that my sleep is still quite fragmented. I'm sleeping a bit longer in my sessions, but I am still waking up 3-4 times per night between sessions. 

Bonjour had talked about how nocturia was a common symptom of sleep apnea and that my body would eventually let me sleep longer without waking up as I got used to therapy. This definitely makes sense, but I'll be honest, I don't know what the time frame on how long this takes to resolve. Could it be weeks? Months? Who knows. I'm slowly starting to sleep in longer intervals, (the longest was 5 hours or so, but I mostly average anywhere from 1-4 hours. 

Anyways, I've restarted this thread because I noticed a common theme when I was studying my arousals in the middle of the night. It seems most of the time right before I wake up, the pressure has increased quite a bit (most likely because of flow limitations). I actually read a very interesting thread about how increased pressure can wake you up (although it was quite long winded, lol). Well, it got me thinking. Since my AHI numbers are excellent, why not reduce the max pressure to see if I can increase my sleeping time without waking up. 

I'm definitely tempted to start playing around with the pressure max and seeing if it won't help fragmented sleep. I did experiment with raising the min pressure from 7 to 9 last night in an effort to reduce flow limitations, and my god was it hard to breathe! (That's what gave me the idea that maybe it was the pressure increases causing fragmented sleep). As always, definitely enjoy hearing what others might think.  

Thank you all and have a nice day.

[Dormeo]

Go for it! The experiment can’t hurt, and it might help. With your very low AHI, adjustments should now be entirely aimed at comfort and restful sleep.

With a low AHI and the pressures moving around in response to FLs, I actually set IPAP =EPAP, to eliminate pressure changes entirely. For me, this was a successful experiment—one less cause for wake-ups. My AHI continues to bounce around between 0 and 1, and it’s mostly composed of CAs that occur after a brief arousal.

If you try this, I’ll be curious to know how it goes for you. Good luck!

[ReturnofXile]

Go for it!  The experiment can’t hurt, and it might help. With your very low AHI, adjustments should now be entirely aimed at comfort and restful sleep.

With a low AHI and the pressures moving around in response to FLs, I actually set IPAP =EPAP, to eliminate pressure changes entirely. For me, this was a successful experiment—one less cause for wake-ups. My AHI continues to bounce around between 0 and 1, and it’s mostly composed of CAs that occur after a brief arousal.

If you try this, I’ll be curious to know how it goes for you. Good luck!

Thank you for the response and offering some suggestions. Interestingly, the results from the titration study finally came in and they recommended a constant 7cm of water pressure throughout the night, although lately I've been on a range from 7cm - 20cm with an EPR of 3.  Your example is actually in line with what the sleep doctor recommended. I picked out the ResMed Airsense 10 Autoset for this exact reason. I wanted the flexibility of being able to try both modes of therapy (constant pressure, or using a range and letting the machine's algorithm do its job). 

I take it to get IPAP = EPAP, I would have to do without EPR, otherwise it would be 7/4. However, I'm hesitant to turn it off. An EPR of 3 was originally recommended to me to reduce flow limitations, which it did actually do. I would think that if you kept a straight pressure of 7/4, then that would minimize pressure disturbances as you would always be inhaling and exhaling with a set pressure. Having said all of that, I do realize that hypothesizing what might happen and what is actually happening with the data are two different things, and what looks good on paper doesn't always translate into good results. All that is to say that the scientist part of me would not dismiss an idea just because it doesn't initially resonate with me. I may very well give your suggestion a shot if I can't get it to work with the above. 

Thank you Dormeo for giving me another idea to potentially use to remedy this problem. I'll be sure to let you know how it goes.  Have a nice day.

[Dormeo]

No, you can keep the EPR. I wrote to you in a early-morning fog, I’m afraid. What I meant to write was that my max =min. Now that I’ve had a cup of coffee, I’m more trustworthy!

So, for example, my max = min = 7.6, and my EPR is 3. So I have 7.6 on inhale and 4.6 on exhale.

Apologies for the mistake!

[SarcasticDave94]

No, you can keep the EPR. I wrote to you in a early-morning fog, I’m afraid. What I meant to write was that my max =min. Now that I’ve had a cup of coffee, I’m more trustworthy!

So, for example, my max = min = 7.6, and my EPR is 3. So I have 7.6 on inhale and 4.6 on exhale.

Apologies for the mistake!

will this help?

[Dormeo]

OH, yeah....

[ReturnofXile]

Okay, so I had my first night with a fixed pressure setting of 7. Overall, I think it was a good step in the right direction. My two main sleep sessions were quite longer than usual, so it did seem that the constant pressure helped me to stay asleep. However, on the flip side there was quite a bit more flow limitation and events specifically RERAs. Despite that, I do feel pretty good. 

So my initial thought (someone please correct me if I'm misguided) would be to slowly increase the fixed pressure by increments of .2 cm, until eventually I can get used to sleeping at a higher pressure as well as eliminating most of those events. Honestly, it looked like a min pressure of 9cm (see chart from previous post) was enough to eliminate most flow limitations and events. 

My question is, is it feasible to work up to such a pressure, like is this something that your body can adapt to, or does it have more to do with your anatomy and physiology that determines what pressure you can handle? 

Any help would be greatly appreciated!

[Dormeo]

Your plan sounds entirely feasible. Always stay at a new pressure for at least a couple of nights. You may be able to move up faster in the 7s than in the 8s—or not. Your experience as well as your numbers will be the key signposts along the way. Keep us posted!