[Diagnosis] modest811 - Therapy Thread

[Geer1]

The higher PS will probably help the F20. Have you tried replacing or washing the elbow? It has filter material in it and can start to get more restricted with time so if it is an older mask might not be venting as well as it used to.

[modest811]

The higher PS will probably help the F20. Have you tried replacing or washing the elbow? It has filter material in it and can start to get more restricted with time so if it is an older mask might not be venting as well as it used to.

Ah, that is a very good point. I have replaced the elbow in quite sometime. I've replaced the straps and the cushion, but the elbow is ollllld. I definitely felt like it wasn't getting air to me as well as before, and the FLs have increased quite a bit with it. Definitely could be the elbow. Just bought a new replacement on amazon.

[SarcasticDave94]

You'll find Trigger has 5 levels, Very Low, Low, Medium (default), High, Very High.

[Geer1]

The only downside to very high trigger is if your data has things like cardiogenic oscillations which can trigger pressure increases too early. Comparing the flow rate chart to your mask pressure chart is the best way to see if machine seems to be in good sync with your breathing, if you see things like two pressure waves per breath etc post an example and can help try and fine tune those settings.

[modest811]

Hey guys, so I switched the VAUTO on friday, had a great sleep as can be seen here: 




But then last night, I put on my dreamwear mask and it was being really loud during inhalation (is this normal for bipap?), so I switched to my f20 again, this time with a new elbow. And then this happened. I was pretty much hyperventilating the entire night. And the flowrate looks completely different than the weird way it was looking before. I was watching a recording of myself in my sleep and sure enough my mask is going up and down really quickly during these moments. 

What is happening?!? I had no issues before and now it seems like my breathing sometimes is absolutely insane. Am I getting too much C02 and that's causing me to hyperventilate? Ever see anything like this before?

[Sleeprider]

The only downside to very high trigger is if your data has things like cardiogenic oscillations which can trigger pressure increases too early. Comparing the flow rate chart to your mask pressure chart is the best way to see if machine seems to be in good sync with your breathing, if you see things like two pressure waves per breath etc post an example and can help try and fine tune those settings.

I don't know if this concern applies here, but the mitigation for using very high trigger with respiratory or cardiogenic oscillations would be to increase TiMin to a longer interval than those oscillations.  

Modest, your Friday results look as good as it gets.  Whatever that is, do it more rather than changing more variables.

[modest811]

Yeah, definitely going back to the dreamwear mask. Just unsure why I was hyperventilating like that in my sleep. I wish I knew what was causing this stuff all of a sudden. Had fine to okay therapy for over a year and now I'm having these issues periodically.

[SarcasticDave94]

Just adding info about the F20 mask, a few years ago ResMed created a new elbow, the QuietAir. It changed the vent holes configuration and placed a white packing material inside. Some, including myself, have experienced more back pressure with this newer elbow. And again, some have experienced black dots forming on that packing. When I was using my F20 mask I used needle nose pliers to pull that packing out. That did seem to reduce the back pressure while making it vent less quiet and becoming more breezy.

I'll link the conversation about it here:

This is the link to the thread beginning

http://www.apneaboard.com/forums/Thread-...tair+elbow

My post about ripping out the packing

http://www.apneaboard.com/forums/Thread-...#pid321624

Post by RayBee with images of old and new style

http://www.apneaboard.com/forums/Thread-...#pid321566

[Geer1]

I don't know if this concern applies here, but the mitigation for using very high trigger with respiratory or cardiogenic oscillations would be to increase TiMin to a longer interval than those oscillations.  

Modest, your Friday results look as good as it gets.  Whatever that is, do it more rather than changing more variables.

It does apply here because modest was having issues on the autoset with cardiogenic oscillations or something else triggering the machine to come out of sync with his breathing causing the odd breathing pattern we have seen with cathyf (who also found improvement turning trigger sensitivity down). 

TiMin is the enemy of cardiogenic oscillations. Locking in the pressure when the machine triggers too early is one of the worst things you can do. Minimizing TiMin is actually better than increasing it. 

Lowering the trigger sensitivity increases the flow rate required to trigger the pressure increase making it so that the pressure increase doesn't get triggered early by cardiogenic oscillations (waits until a larger flow rate/full inhale before doing so). Resmed titration protocol document even specifically says to use lower trigger sensitivity for cases with cardiogenic oscillations so as to avoid this.

I am aware of two main reasons to adjust trigger sensitivity. Higher can help with centrals, lower helps avoid early triggering and coming out of sync in cases with cardiogenic oscillations etc. The people that struggle with both issues are the ones that get stuck having to compromise depending on which is causing the bigger issue.

[Geer1]

That breathing example is interesting and you were breathing fast and exhaling hard (but not inhaling hard like I did at one point hyperventilating in sleep due to plugged filter).

I assume the issue is related to venting, the dreamwear mask vents far more than the F20 and the restriction of F20 is what we were already curious about hence the new elbow to try and solve that. Sounds like that new elbow didn't make enough of a difference, can you feel the air venting from it? I believe you can still get old venting elbows for the F20 but they won't be as quiet, worth considering trying if you like the fit/comfort of mask better. You could try pulling filter material out as Dave mentioned as well (I would do so from your old one if you didn't already throw it away).

I like that the F20 is so quiet but I think it is more likely to have venting issues making it harder to exhale.

Edit: You should look at the moment that breathing began and compare breathing to mask pressure just to make sure it wasn't caused by machine coming out of sync. I could see this as being the case where machine gave you an early breath and then you got out of sync with double breaths. If I remember right you only really see the cardiogenic oscillations with F20 and that would make you more prone to such an issue.