What Happened!?!? Evil chinstrap????

I've been pretty happy with my numbers over the past month, with AHIs in the 1.0-2.5 range. Over the past few days, however, I've noticed a little more mouth leaking at night, with charts similar to this one:



So last night I decided to try wearing a velcro chinstrap to ensure that my mouth remained closed. Big change! But not for the better - I ended up with my worst numbers since my first week on the machine. What does this mean? Is the issue that I have not been getting sufficient air flow through my nasal pillows and have been compensating by mouth breathing - and now that I shut my mouth leaks with the chinstrap, the lack of oxygen became more evident as the machine struggled to manage multiple OAs? Or is it related to the flow limit #s, which seem much higher? I find this all very disturbing! Thanks for any insight! Last night's chart is below:

chinstraps tend to push your jaw backwards, closing off your airway more, needing more pressure to compensate, and you've prevented the machine from being able to respond with your effective max pressure of 13.

Thanks that's really interesting. Does that jaw movement tie in to the flow limit numbers too?

RichCee wrote:Thanks that's really interesting. Does that jaw movement tie in to the flow limit numbers too?

flow limitation is caused by a narrowing of the airway, so, yes.

Thanks. One follow up - how concerned should I be in general about occasional mouth breathing that does not result in leak rates that are very high, and does not seem to impact the CPAP's ability to respond to and manage pressure well?

RichCee wrote:One follow up - how concerned should I be in general about occasional mouth breathing that does not result in leak rates that are very high, and does not seem to impact the CPAP's ability to respond to and manage pressure well?

As long as it doesn't wake me up often...I ignore it.
Sometimes the cure is worse than the disease.
I also don't panic if I spend 5 minutes in large leak territory as long as I sleep through it.

Thank you Pugsy & Palerider. Had no idea a chinstrap could exacerbate air flow problems like this. As far as the occasional mouth breathing, it doesn't seem to be resulting in a problem w the AHI or other data, so I should probably chill out about it. I do tend to clench my teeth a lot however, so I probably need to address that next and in a way that doesn't mess up the good #s I had been getting on CPAP.

Not all chin straps will create that sort of problem with everyone. It's going to depend on the kind of chin strap and how tight a person makes it and their general facial structure.
Since you know it creates a problem for you and the mouth breathing you are trying to prevent is minimal...I wouldn't bother with it.
Now if the mouth breathing had been serious and creating a big problem then if the chin strap was deemed to be the best solution then you could have increased the pressure to compensate for the increase in need.
But for me...I see no reason to have to do that unless the mouth breathing is seriously negatively impacting therapy.

The teeth clinching...I don't know what to offer about that. I seem to be doing a bit of that myself lately and along with it comes some TMJ discomfort. I haven't decided if I want to go back to the Tap Pap mask yet...it has a mouth guard. I have been sitting on the fence about swapping out masks again.
The TMJ is getting pretty aggravating though. Maybe next time the damn thing locks up again I will get off my lazy butt and bring out the Tap Pap and take the time to do another mouth guard fitting.
I like the mask..I just need to refit it and that takes some work and I am in lazy mode right now.

Thanks Pugsy - how would you decide whether or not the mouth breathing was a problem? Would it be whether it woke you up? Would it be whether the leak rate on SleepyHead was above some sort of critical level? Would it be the machine trying to climb above your ceiling pressure level? Thanks for any insight. I don't *think* its a problem, but I want to make sure I am not missing something.

RichCee wrote:Thanks Pugsy - how would you decide whether or not the mouth breathing was a problem? Would it be whether it woke you up? Would it be whether the leak rate on SleepyHead was above some sort of critical level? Would it be the machine trying to climb above your ceiling pressure level? Thanks for any insight. I don't *think* its a problem, but I want to make sure I am not missing something.

Good questions, I'm looking forward to reading the response myself.

How do I decided if mouth breathing is a problem or not?.. or really any leak not just mouth breathing leak.
First thing with anything...does it wake me up often? If not...no problem.
Second thing...I look to see how far into large leak territory that I went...was it just barely into large leak territory with ceiling being 25 to 29 L/min. It won't start negatively impacting therapy all that much until it starts going over 30 L/min. So if I don't go over 30 L/min...no problem.
Third thing...I look to see how much time was actually spent in large leak territory and at the same time evaluate how much time might have been spent over 30 L/min. Short periods of large leak even well into large leak territory aren't the end of the world. 5 minutes here and there at 40 L/min...not that critical in terms over overall therapy. Now 50 continuous minutes at 40 L/min...that's a problem.

So I look at the big picture and not just numbers by themselves.

ResMed uses the red line of 30% or more of the night in large leak before you get Mr Frowny face.
It takes a lot of big leak to add up to 30%...I prefer 10% myself. Random nights with more than 10% of the night in large leak....I don't worry about anything that is random or rare.
Nights where the leak is consistently more than 10 % of the night in large leak (over 30 L/min in my book) is when I start looking at potential causes and deciding what to do.
99% of the time I just need to do something with the mask...either new pillows or the headgear is too stretched out and its mask movement leak and not mouth breathing leak.

My first thing always though....does it wake me up often...If I am sleeping soundly and feeling decent during the day then I don't worry about minor imperfections in the leak line.
My sleep is fragile enough without adding something else to bug me during the night just to fix 15 minutes of maybe mouth breathing (because it could just as easily be mask movement leak).
I could get a nice perfect leak line if I wanted to go to the trouble but I would have to sacrifice sleeping soundly and I don't want to do that just for minor short lived large leaks no matter what the reason.

Above numbers assume a ResMed machine.
I do have a Respironics machine and since it reports leak differently I do have different "numbers" for large leak territory.
So any of you Respironics machine users...don't go by the 24/30 L/min red line...it won't work with your machines because of how Respironics reports the leaks. It will scare you to death and there's no need.

Very helpful Pugsy, thank you very much.

Pugsy wrote:

RichCee wrote:One follow up - how concerned should I be in general about occasional mouth breathing that does not result in leak rates that are very high, and does not seem to impact the CPAP's ability to respond to and manage pressure well?

As long as it doesn't wake me up often...I ignore it.
Sometimes the cure is worse than the disease.
I also don't panic if I spend 5 minutes in large leak territory as long as I sleep through it.

fo what it's worth, Rich... +1 on what Pugsy says.