Help needed

[SteveC]

Hi all,

Would someone be able to help me understand what is happening here?
AHI is fine for a few hours, then jumps. I think this is my middle of night wakeup time going to the bathroom. 
I also notice at this point the flow rate goes very high. Why?
These are also mostly CA events. 

Regards,

Steve

   

   

[staceyburke]

Your min pressure is not high enough to use the EPR (exhale Pressure Relief).  I won't spend much time on this but All cpap machine can only go as low as 4 and no more.  When you use EPR the min 5 Epr 3 the exhale (min) is 4 because that is as low as it can gol  YOu need to raise the imn to at least 7Min -3epr=4 inhale


Leave all other settings the same and change min 7

[SteveC]

Thanks, 

I'll give that a go. What if I turn EPR off?

Regards,

Steve

[staceyburke]

If you want to try that it is fine.  You should not feel much difference and see if the events are less. But I would still raise the min to 7. 4 is to low for most adults, 4 would be for a child.

[SteveC]

Thanks,

I only plan to make one change at a time.

[CPAPfriend]

hey SteveC

you might have high loop gain, which sort of means that your breathing pattern can be disturbed into a feedback loop quite easily. Also worth noting are the leaks that coincide with the cluster of CAs. Leaks are known to cause and exacerbate CAs, so I recommend taming them, despite them already being relatively low on average. It's proposed that this happens because the leak washes out the anatomical deadspace, washing out some of the CO2 that is responsible for building your respiratory drive.

[SteveC]

hey SteveC

Also worth noting are the leaks that coincide with the cluster of CAs. Leaks are known to cause and exacerbate CAs, so I recommend taming them, despite them already being relatively low on average. 

Interesting. Not sure how I can reduce leaks, mask fit seems ok, perhaps the mask is moving during the night.

I have attached last night data, seems to show the same thing. some of the leak rate spikes are due to me taking the mask off to go to the bathroom in the middle of the night.



   

[Jay51]

Here are some tips on reducing leak, SteveC:  

Mask Primer

Absolutely great point CPAPfriend (and great thinking) about leaks and increased CA's by reducing the anatomical dead space in the mask (filled with CO2).  An EERs increases this space (and Co2).  I have seen leaks lining up with CA's in charts, but couldn't understand the correlation (why).  

Interestingly, the area from the tip of the nose to the larynx (area through the turbinates) makes up around 25% of the anatomical dead space.  I didn't realize it was that big.  So longer, more forceful exhalations can significantly reduce CO2 also.  And shorter the opposite.

[SteveC]

Thanks,

Here is last night's data. I think I might have started mouth breathing again, as I wake up with a very dry mouth. I do have a chin strap, but stopped using it as the mouth breathing went way, as a Resmed tech said it would.

Last night is interesting, AHI shot up markedly in the first few hours, then settled down. not sure what this indicates.

I am also using the Resmed N30I mask as I have a full beard

Regards,

Steve

   

   

[Deborah K.]

Have you posted a redacted copy of your sleep study?  That would help us a lot in figuring out what is going on.