How do we understand mouth leak?

[burc2006]

Hello everyone,
Everyone is talking about mouth leak, can we see mouth leaks from the results?
Yesterday, my leak level seen on S9 Elite screen was 12 L/min, is it too much?
When I check the graphs on resscan or sleepyhead software, I cannot see big leaks when I am sleeping (I only see some big leaks at the 1st moments when I go to bed caused by reinstalling mask by lifting it up.
So, if I am sleeping with my mouth open, can I see this in graphs with very big leaks?
2nd question: If I open my mouth during sleep time, I have very very sore throat and nose as soon as I open my mouth, so I assume that if I sleep with mouth open, I should be waking up or close my mouth immediately.
Thanks for your replies.

[Pugsy]

ResMed says they can handle leaks up to 24 L/min so your 12 L/min is probably an indication of leaks not being out of control. Is this number the average leak or the 95% leak?
Best thing is to look at the graph of the leak and see if you went over the 24 L/min line and if you did was there much time spent there?
95% leak just means that for 95% of the time you were at or below that leak level. So at worst 5% of the time you were above it.
So if you look at that leak line and it stays well below that 24 L/min line then your leaks are well managed.

[burc2006]

I will check. However if my mouth is open during sleep, my leaks will be over 24 L/min?

[torontoCPAPguy]

The CPAP data does not care where the leak is happening; it simply reports the leak. It could be coming from your mouth, leaky mask fit, or any other orifice you care to think about (I prefer not to).

ANY leakage is undesirable and tends to cause various issues; dry mouth being the most common I would think.

[Pugsy]

However if my mouth is open during sleep, my leaks will be over 24 L/min?

It depends. I sometimes wake up (usually on my back) with my mouth open and a very dry mouth but when I look at the reports I don't see any unusual spikes in the leak line and certainly nothing anywhere near 24 L/min line so I assume that my time with my mouth open was very brief and wasn't enough to show up on the machine and if it didn't how up then it probably didn't impact my therapy.

As torontoCPAPguy has said. The machine doesn't know what causes a leak...it just reports them.

If your leak line is staying well below the 24 L/min line then we would assume that if you are mouth breathing then it is likely very minimal and probably not impacting your therapy.
Now if you are waking often with a dry mouth and are uncomfortable..then anything that causes frequent awakenings is unwanted even if it is a minimal leak.

If you are trying to determine if you are mouth breathing just by the leak number....we can't tell except that if you are then it doesn't seem to be a huge amount.
I would shrug my shoulders and not worry about it if you are sleeping soundly and not having dry mouth.

[burc2006]

my mouth is dry even before going to bed, however I dont feel very thirsty in the morning after I wake up. Sometimes I wake up at night to drink some water, but just once and I think it is very dependent on what I eat at night.
Before CPAP, I never breath from nose, always mouth open but after CPAP even in titration technician said my mouth was closed.

[robysue]

my mouth is dry even before going to bed, however I dont feel very thirsty in the morning after I wake up. Sometimes I wake up at night to drink some water, but just once and I think it is very dependent on what I eat at night.
Before CPAP, I never breath from nose, always mouth open but after CPAP even in titration technician said my mouth was closed.

There are many, many things that can cause dry mouth problems. Mouth breathing while on CPAP is one of them. But so can many medications, including many OTC drugs. Do you take anything on a regular basis? Maybe an allergy pill perhaps? Dehydration can also cause a dry mouth. How much liquid do you typically consume in a day?

As for mouth leaks: They may or may not show up in the leak graph. If you open your mouth for just a few seconds and the machine doesn't sample during that time, it won't show up. And some folks have mastered a trick of keeping the tongue so soundly on the top of the roof of their mouth that it provides enough of a seal from the upper airway that they can open their mouth briefly without it triggering a huge leak. But for the people who have serious mouth leak problems, the mouth is open for long periods of time and the tongue is not blocking the oral cavity off from the upper airway, and the air largely goes in the nose and out the mouth as a significant leak.

Given your leak numbers and the fact that you have a dry mouth before bedtime and the fact that the tech said your mouth was closed during the titration study, the mouth breathing that you're doing is probably pretty minor. It could be that CPAP air is leaking into your mouth, but not forcing the mouth to open up wide, and so you're only leaking a bit out the corner of your mouth---not enough air to affect therapy (i.e. small leaks), but it is a potentially serious comfort issue: If the dry mouth is causing you problems with being comfortable enough to get to sleep and stay asleep, you need to address the problem. Upping the humidity might help if you are leaking a tiny bit of air from your closed lips. Making sure you have a glass of water right before bed may help. Check all your medicines to see if dry mouth is a side effect. And consider getting something like Biotene Mouthwash to help with the dry mouth.