RE: Frustrated, Cannot get AHI Down After 2 Weeks
A couple more points:
Remember that the purpose of CPAP and sleep therapy is to ensure that you breath as necessary while you're sleeping and that your blood oxygen levels remain stable. If you're breathing through your mouth, you're breathing. Nothing is necessarily wrong. It is perfectly normal to breath through your mouth some of the time, both while you're asleep and while you're awake. Just ask your dentist about all of the people who complain to them about morning dry mouth and the wide variety of products to treat it. And if that's a problem for you, keep a glass of water beside your bed and take a swig if you wake up with a dry mouth.
To be sure, if you have a nasal pillow, your machine will think there's a problem when you breath through your mouth. It will record that you are having an apnea, even if you're breathing quite normally through your mouth, and aren't having an apnea at all. And if you have machine that delivers FOT pulses, the machine will start shaking your nose, and disrupting your sleep, even though there is no reason at all for it to do so. You'll probably think the mouth breathing is the problem, and yet you probably were breathing through your mouth during part of the night for the last 20 years and it never bothered you.
Central apneas are also quite normal, though not for everyone. For people who get them, they are very common while you're awake. People stop breathing for 10+ seconds throughout the day without giving it a second thought. If you put on a pulse oximeter, you'll find that you can hold your breath for 10 seconds once a minute, all day long, without having any real impact on your blood oxygen levels. That's equivalent to an AHI of 60! During sleep, people often have central apneas during REM sleep, which is not surprising since REM sleep is when you dream of doing things that you might do when you're awake. And since REM sleep increases later in the night, you'll see larger clusters of central apneas the longer you sleep.
Resmed has aggressively pushed people to buy their very expensive ASV machines to treat central apneas. I think that's part of the reason why Resmed doesn't want to allow people to disable the FOT pulses on their cheaper machines. The pulses make the machines unusable for people who have centrals, and force them to update to the more expensive machines wrongly believing that the centrals are keeping them awake when it is actually the FOT pulses delivered by the machine that is doing so. Not surprisingly, the more expensive ASV machines don't deliver FOT pulses at all, nor do the machines used in sleep labs.
There is very strong evidence that ASV machines **prevent** centrals, by shoving air down your throat, but not so much evidence that they result in better overall outcomes in the long-term. In the short-term, people who switch to them may just be sleeping better because they don't send FOT pulses that wake them up every time that they have a central.
And for a small group of people, ASV machines have already been *proven* to increase the long-term risk of heart attack and death. I suspect that as they continue to be used, more data will be available on this subject, and it won't surprise me at all if those machines turn out to have worse long term outcomes than just leaving centrals alone.
If you do get a camera system to record yourself, put it to the side of your bed so that you can record your face and your torso. Although the rise and fall of your chest is not easy to observe at normal playback speeds, it is very obvious at 2x and 3x playback. If you see your chest rise and falling at the same time that the machine records a cluster of apneas, watch for skips in the rise and fall. If you see continuous rise and falling, then you're not having a central. Next, check your mouth to see if it is open and listen for breathing during that time at normal speeds. If your mouth is closed and your chest is rising and falling but the machine records no airflow, then you're most likely having an obstructive apnea. If your mouth is open and you can hear breathing, you're fine b/c you're breathing. If your mouth is closed and your chest has periods where it is not rising and falling, you're having central apneas.
And definitely get rid of any machine that gives you FOTs. They're not very effective at recognizing obstructive vs. central apneas, will give a wrong answer 100% of the time when you're breathing through your mouth with a nasal pillow mask, and will almost certainly disrupt your sleep. If you want to stick with ResMed, the cheapest ResMed AirSense 10 CPAP will not deliver FOTs and the VAUTO can be set to do so as well (S-mode with easy breathe off).
Finally, EPR and Bi-Level are the enemy of people who have centrals. Just use the lowest fixed pressure that keeps your airway open.
Remember that the purpose of CPAP and sleep therapy is to ensure that you breath as necessary while you're sleeping and that your blood oxygen levels remain stable. If you're breathing through your mouth, you're breathing. Nothing is necessarily wrong. It is perfectly normal to breath through your mouth some of the time, both while you're asleep and while you're awake. Just ask your dentist about all of the people who complain to them about morning dry mouth and the wide variety of products to treat it. And if that's a problem for you, keep a glass of water beside your bed and take a swig if you wake up with a dry mouth.
To be sure, if you have a nasal pillow, your machine will think there's a problem when you breath through your mouth. It will record that you are having an apnea, even if you're breathing quite normally through your mouth, and aren't having an apnea at all. And if you have machine that delivers FOT pulses, the machine will start shaking your nose, and disrupting your sleep, even though there is no reason at all for it to do so. You'll probably think the mouth breathing is the problem, and yet you probably were breathing through your mouth during part of the night for the last 20 years and it never bothered you.
Central apneas are also quite normal, though not for everyone. For people who get them, they are very common while you're awake. People stop breathing for 10+ seconds throughout the day without giving it a second thought. If you put on a pulse oximeter, you'll find that you can hold your breath for 10 seconds once a minute, all day long, without having any real impact on your blood oxygen levels. That's equivalent to an AHI of 60! During sleep, people often have central apneas during REM sleep, which is not surprising since REM sleep is when you dream of doing things that you might do when you're awake. And since REM sleep increases later in the night, you'll see larger clusters of central apneas the longer you sleep.
Resmed has aggressively pushed people to buy their very expensive ASV machines to treat central apneas. I think that's part of the reason why Resmed doesn't want to allow people to disable the FOT pulses on their cheaper machines. The pulses make the machines unusable for people who have centrals, and force them to update to the more expensive machines wrongly believing that the centrals are keeping them awake when it is actually the FOT pulses delivered by the machine that is doing so. Not surprisingly, the more expensive ASV machines don't deliver FOT pulses at all, nor do the machines used in sleep labs.
There is very strong evidence that ASV machines **prevent** centrals, by shoving air down your throat, but not so much evidence that they result in better overall outcomes in the long-term. In the short-term, people who switch to them may just be sleeping better because they don't send FOT pulses that wake them up every time that they have a central.
And for a small group of people, ASV machines have already been *proven* to increase the long-term risk of heart attack and death. I suspect that as they continue to be used, more data will be available on this subject, and it won't surprise me at all if those machines turn out to have worse long term outcomes than just leaving centrals alone.
If you do get a camera system to record yourself, put it to the side of your bed so that you can record your face and your torso. Although the rise and fall of your chest is not easy to observe at normal playback speeds, it is very obvious at 2x and 3x playback. If you see your chest rise and falling at the same time that the machine records a cluster of apneas, watch for skips in the rise and fall. If you see continuous rise and falling, then you're not having a central. Next, check your mouth to see if it is open and listen for breathing during that time at normal speeds. If your mouth is closed and your chest is rising and falling but the machine records no airflow, then you're most likely having an obstructive apnea. If your mouth is open and you can hear breathing, you're fine b/c you're breathing. If your mouth is closed and your chest has periods where it is not rising and falling, you're having central apneas.
And definitely get rid of any machine that gives you FOTs. They're not very effective at recognizing obstructive vs. central apneas, will give a wrong answer 100% of the time when you're breathing through your mouth with a nasal pillow mask, and will almost certainly disrupt your sleep. If you want to stick with ResMed, the cheapest ResMed AirSense 10 CPAP will not deliver FOTs and the VAUTO can be set to do so as well (S-mode with easy breathe off).
Finally, EPR and Bi-Level are the enemy of people who have centrals. Just use the lowest fixed pressure that keeps your airway open.
