[Pressure] Need your opinion on possibly adjusting pressure range

[wampeter]

I’ve been on CPAP for almost a year now. Overall AHI score for the last year is 3.90, mainly obstructives. Prescribed pressure is 4-10, machine is below 6.8 90% of the time, around 4-5 on average. Main issue and why I think the prescribed pressure is problematic: in my case obstructives are not distributed evenly and usually occur in bulk, mainly near the morning. What would be the best strategy in adjusting the pressure if I’d like to prevent them? It’s really devastating, especially if I manage to sleep longer in the morning I feel battered, also I’m still afraid of complications, despite the "acceptable" AHI, which could be lower anyway. My goal is to prevent those worst apnea sprees (no idea how to call it better, I hope you get what I mean). Attaching some screenshots.

[Gideon]

Welcome to the forum.


Based on the OA numbers I would raise your minimum to 6 to give your machine a better base to treat your events from and thus decrease your OA numbers.
The fact that the OAs are clumped, not evenly spaced implies a positional apnea element to this.  This could easily be handled with a soft cervical collar (loosely fitted) or it's cousin the anti-snoring collars (no foam in the back of the collar).
Additionally, I see your minimum pressure is 4.  Many users find 4 cmw as a difficult to handle (not enough) pressure.  You did not mention any discomfort with your current settings but if you feel this increase your min pressure to 6.

A key is to only make one change at a time so you know which change made the difference.

[wampeter]

Thank you for the answer.

> The fact that the OAs are clumped, not evenly spaced implies a positional apnea element to this

I came up with that at some point and have been sleeping with a tennis ball attached to my back since. AHI lowered by about one point, so positional apnea is probable (unless it’s a coincidence). Correct me if I’m wrong but I guess it can be also REM-related. My situation is complicated as I did not succeed on sleep studies, as was not able to fall asleep and/or maintain sleep, tried twice (I mean had two separate sleep studies, not that I tried to fall asleep twice on a single one  ). Therefore I don’t really know my AHI without CPAP, not to mention details as position or stage of sleep where apneas occur the most.

> Based on the OA numbers I would raise your minimum to 6 to give your machine a better base

TBH I expected that advice would be rather to raise the maximum (or both). I’m not saying you’re not right on that, I just don’t quite understand the mechanism or reasoning behind this. So does it mean that those clumped apneas would be  nipped in the bud, so to speak, and it won’t get to the point where maximal pressure of 10 would not be enough to treat them? I don’t quite get the notion of "better base". I would be grateful for clarifying that. I still not quite understand if CPAP is more about preventing apneas or opening the  airways after they have collapsed.

> This could easily be handled with a soft cervical collar (loosely fitted)

Never heard of this method. Will try for sure if that might help.

[Gideon]

Lost my reply,  try 2

soft cervical collar (loosely fitted) is a "new" technique in use since 2016.  To my knowledge, this is/was not recognized by the medical community.  It was a user that brought this forward and it has been extremely successful for positional apnea and also useful for some leak management and mouth breathing.  Much more successful than the chin strap.  And yes, the clumping could be caused by REM.  

We want to raise the "base" for the algorithm because the Dreamstation tends to respond fairly slowly to events and by raising the "base" or min pressure we are able to shorten the response time to handle events.  Your events are handled by the high pressure so there is no need to adjust that.

Your numbers are acceptable (< 5 AHI) to the medical community so we only want to make fairly small changes.

Fred

[wampeter]

Ok, so I followed Bonjour’s advice and raised the minimal pressure to 6 (so now I use 6 - 10). It’s been a month now, so time for conclusions. Good thing is that I adapted to the new pressure in no time. Though, I’m afraid raising the minimal pressure hardly resolved my issue. Although overall AHI seems to have dropped a bit (for the timespan since the new pressure was applied it is 3.21, previously it was 3.9) – but I'm not even sure if that’s a real effect as I had some nights with many awakenings and/or shallow sleep because of the newborn and stuff. Anyway… as said, the issue has not been resolved: apneas, when/if occur, are still clumped within one or two around-an-hour spans, which results in an AHI for the whole night that is considered technically "treated". Here is for example what happened last night, which happens to be one of the worst since the pressure mod, AHI > 5 (attaching general statistics also).


> Your events are handled by the high pressure so there is no need to adjust that.

Actually I’m not quite convinced about that. Could you look at the night result in the attachment and confirm that? And how do I actually know that maximal pressure is high enough? I assume there must be some rule of thumb here.

[Dog Slobber]

"Actually I’m not quite convinced about that. Could you look at the night result in the attachment and confirm that? And how do I actually know that maximal pressure is high enough? I assume there must be some rule of thumb here."

You know your max pressure is high enough because the machine rarely gets to it.

Raising your minimum can help keep your airways open preventing the need for higher pressures. Pressure increases can be slow to respond. in the time it takes to increase pressure 4, many Apneas or Hypopnea may have occurred. Setting your minimum higher can shortcut that wait time.

My initial APAP settings were 7-14. The machine spent the time see-sawing up and down and spending a lot of time at 14.

To many the intuitive thing to do was to raise the maximum thinking I needed more pressure. By raising my minimum (9.6), my machine rarely approaches the maximum and my AHI is much lower. I'm now at 9.6-12.

[Melman]

You didn't mention that you tried the soft cervical collar. Your apneas are still clustered and I believe the collar will correct that.   I had similar clustering and a soft cervical collar has eliminated most of my OAs.  It works by preventing your chin from tucking towards your chest which restricts your airway. I find with the collar I can sleep in any position and still maintain a low AHI. I encourage you to give it a try if you haven't already.  The tennis ball may keep you from sleeping on your back but it does not prevent chin tucking when side sleeping.

[Walla Walla]

You should bump the minimum pressure up 1cm to 7cm.

[Gideon]

I see positional clusters that could be helped with a soft cervical collar.  If you want to raise your max pressure, you could raise it to 20 cmw and not impact your therapy. Your max pressure was 9.9.  I have mine set at 25, but I no longer get high pressures at all.

Without the positional apnea your numbers would be excellent, so the important question, the one that should drive changes is "How do you feel?"

[wampeter]

Thank you all for your answers. I really appreciate it.

> You know your max pressure is high enough because the machine rarely gets to it.

Well, in general that would be correct, though my reasoning is that those rare occasions are the moments where my apnea really happen. I'm not sure if max pressure is enough at those times, enough to handle the occurring apneas. To me intuitively it should work this way: I start to have more apneas at some point, CPAP raises the pressure, higher pressure prevents the following apneas from occurring. And that apparently does not work that way as in my case apneas are possibile to occur even on the maximal pressure, so it's not enough to prevent the airways from collapsing.

 > You didn't mention that you tried the soft cervical collar. Your apneas are still clustered and I believe the collar will correct that. I had similar clustering and a soft cervical collar has eliminated most of my OAs.

> I see positional clusters that could be helped with a soft cervical collar. 

I wanted to try resolving the issue with CPAP alone first, and try another stuff if it's not enough. Also, as you Bonjour said, adding multiple variables at once is a bad idea. But as it’s so highly recommended by you guys, I'll try that as the next step and  not raising the maximal pressure.

> so the important question, the one that should drive changes is "How do you feel?"

Recently not bad, but actually I'm very careful when comes to establishing any linkages, how  treating sleep apnea affects my general "being" that is. Too much noise, too much confounding factors, biases, possible placebo effects (and nocebo as well - I might tend to feel bad just because I know I had a higher AHI), especially that day symptoms of SA are non-specific. And in general I have more apneas when I sleep longer and probably deeper, so the effects might be opposing. Gosh it's complicated.... In short: I don’t know. Let alone the possibile complications of those apneas. That's why I believe the numbers is what should drive changes.