Doctor told me "some people just don't tolerate CPAP"

[snarch]

Hi all. I've been trying to use CPAP unsuccessfully for over a month. I either rip the mask off in my sleep, or my AHI with CPAP is above 5, or both. When I told me doctor about my struggles he responded with the statement above. I don't understand, outside of complex sleep apnea, is it true that CPAP just doesn't work for some people? Do I have complex and he just didn't want to say it directly? Here's my data from last night.



Initially my doctor had my range set at 6-18. I assumed my high AHI was caused by the wide range so I asked him to narrow it and he said my data showed that the pressure almost always set itself around 8.9. He narrowed it to 8-12 but then it began to set itself to 11. This is when I started seeing the clear airway events so I lowered it to 8-9 myself. Except the clear airway events haven't gone away. Here is the data from the single successful night I've had:



How can it be that an identical pressure treated me one night but causes so many clear airway events just a few weeks later? Have I developed complex sleep apnea? The only other changed variable is I stopped wearing my chinstrap because I believe I no longer need it to sleep with my mouth closed, which, to my understanding, is supported by the low leak rate from last night.

Any advice would be much appreciated.

Edit: I just noticed that the pressure during the longest period of uninterrupted sleep on the successful night was between 6 and 7! Is it possible all of my problems are caused by the pressure still being too high? Why would the machine adjust to 8, 9, 11, when 6/7 seems to work fine? Also, I thought "95%" referred to the pressure that the machine spent 95% of its time set at, if I was between 6 and 7 for several hours why would the 95% be 8.9?

[Stom]

"Also, I thought "95%" referred to the pressure that the machine spent 95% of its time set at"

It means you were at or **below** that level for 95% of the time.

"Why would the machine adjust to 8, 9, 11, when 6/7 seems to work fine?"

Because 6/7 doesn't work for you all the time. The machine looks at your respiration air flow graph and adjusts the pressure based on obstructive events, such as snoring, flow limitations, hypopneas and apneas. If you see the pressure increasing, it's because you had obstruction and needed more pressure. Sleep apnea can be pretty variable, and can even vary greatly with what position you are sleeping in. This is why auto adjusting PAP machines are so popular over fixed pressure machines. So even if 6-7 works for you one night, it might not be enough for the next night. You need more than one night to determine the range of pressures. And it takes weeks or months for treatment induced centrals to show a trend (up, down, or the same). So your centrals could get better, worse or stay the same. There are other machines for people with centrals (ASVs), but the standard baseline for prescribing them is 15 central apneas per hour. Less than that seems to be a bit of a grey area.

[greatunclebill]

95% refers to 95% or below. if you're at 10 for 5% of the time and 7 for 90%of the time you would be at 10 or below for 95% of the time. it's not a number to worry about.

you need to find a new board certified pulmonologist sleep doctor, preferably younger. if someone doesn't adjust to cpap they either don't want to or the doctor does not understand sleep medicine.

[snarch]

One other detail I should mention- I just remembered the for the second half of the successful night, during that long period of uninterrupted sleep, I switched over to a pillow mask. Is this why the pressure is so much lower? How drastic are the pressure differences of various masks? I'm not sure if I should set my nasal mask range to 6-7 or just try to switch to pillows with a wider range.

[Stom]

One other detail I should mention- I just remembered the for the second half of the successful night, during that long period of uninterrupted sleep, I switched over to a pillow mask. Is this why the pressure is so much lower? How drastic are the pressure differences of various masks? I'm not sure if I should set my nasal mask range to 6-7 or just try to switch to pillows with a wider range.

Two separate issues could be at work.

First, at least one study showed that nasal masks can work with lower pressures than a full face mask. So mask choice can make a difference in the needed treatment pressures. I assume, but don't know, that there may be treatment differences between pillows and other mask types.

Second, the PAP machine doesn't have a pressure sensor inside your mask. Instead, it has a pressure sensor inside the machine and has to calculate the mask pressure (treatment pressure) based on the the type of hose and mask you have entered into the machine's setup menu. If you didn't change the mask type in the set up menu when you changed masks in the middle of the night, then the calculated pressure may be inaccurate.

[snarch]

One other detail I should mention- I just remembered the for the second half of the successful night, during that long period of uninterrupted sleep, I switched over to a pillow mask. Is this why the pressure is so much lower? How drastic are the pressure differences of various masks? I'm not sure if I should set my nasal mask range to 6-7 or just try to switch to pillows with a wider range.

Two separate issues could be at work.

First, at least one study showed that nasal masks can work with lower pressures than a full face mask. So mask choice can make a difference in the needed treatment pressures. I assume, but don't know, that there may be treatment differences between pillows and other mask types.

Second, the PAP machine doesn't have a pressure sensor inside your mask. Instead, it has a pressure sensor inside the machine and has to calculate the mask pressure (treatment pressure) based on the the type of hose and mask you have entered into the machine's setup menu. If you didn't change the mask type in the set up menu when you changed masks in the middle of the night, then the calculated pressure may be inaccurate.

Thanks for your reply, I did change the mask setting.

[chunkyfrog]

"Some people don't tolerate . . . "
If you have had some success, then you are not likely to be one of those people.
Some of the things that shoot out of doctor's mouths make me wonder
whether they paid attention in school.

[Jas_williams]

A large percentage of your events in the last graph are clear airway were you wake during that time when most of them occurred ?

You can zoom in to the Air flow and check if they are real CA’s


They will reduce over time you could also try reducing the EPR to 2 and see if that reduces the amount of CA’s happening over night, but I would suggest that they will reduce on their own over the next month or so. If they don’t then it will need raising addressing with your doctor.

[chunkyfrog]

Lean on your sawbones if he seems reluctant to WORK for your success.
His previous statement sounds like he might be a premature towel thrower.
Do not let him get off easy.

[snarch]

A large percentage of your events in the last graph are clear airway were you wake during that time when most of them occurred ?

You can zoom in to the Air flow and check if they are real CA’s


They will reduce over time you could also try reducing the EPR to 2 and see if that reduces the amount of CA’s happening over night, but I would suggest that they will reduce on their own over the next month or so. If they don’t then it will need raising addressing with your doctor.

I am fairly certain I was asleep for those events. I did some googling regarding EPR and I think I may just turn it off altogether?

[ChicagoGranny]

so many clear airway events ... Have I developed complex sleep apnea?

Go to your Sleepyhead display for 9/14 and click on the Events tab which is just underneath the date. You can see each event's length. Let us know how the CAs lengths range.

In case no one has said it yet, the machine does not know whether you are asleep or awake. When people change position in bed, it's common to reflexively hold their breath. This can be reported as a CA.

[snarch]

so many clear airway events ... Have I developed complex sleep apnea?

Go to your Sleepyhead display for 9/14 and click on the Events tab which is just underneath the date. You can see each event's length. Let us know how the CAs lengths range.

In case no one has said it yet, the machine does not know whether you are asleep or awake. When people change position in bed, it's common to reflexively hold their breath. This can be reported as a CA.

Is the number in parentheses the length? If so, out of 12 events, 5 of them were below 15 seconds, the rest were between 20 and 30. So you're saying I can ignore the ones below 15 seconds?

[Stom]

Is the number in parentheses the length? If so, out of 12 events, 5 of them were below 15 seconds, the rest were between 20 and 30. So you're saying I can ignore the ones below 15 seconds?

I don't think that is quite what she's saying, rather, that if you aren't asleep, then what the machine scores as a CA isn't a sleep apnea. In a sleep lab the technician scores whether you are asleep based on the EEG, and only events that occur when you are asleep count. Your CPAP machine don't know if you are asleep, and counts every event, so it can over count central apneas. Lot's of my centrals are when I'm awake, or transitioning back to sleep. I think only one of these images has a "real" CA that occurred while I was asleep.

This I know is while I was awake this morning before getting up and shouldn't be counted as part of my AHI, but I wouldn't necessarily know that just from looking at the graph:

Screen Shot 2018-09-15 at 11.50.53 AM.png (28.78 KiB) Viewed 2267 times

Based on the irregular breathing pattern, this looks like I woke up before the centrals. I don't know if it counts. I think it might be what some folks here call "sleep/wake junk":

Screen Shot 2018-09-15 at 11.49.28 AM.png (36.16 KiB) Viewed 2267 times

And this looks like a "real" central (but it's not the only way "real" centrals look, I just chose a clear example that I'm pretty sure of):

Screen Shot 2018-09-15 at 11.40.32 AM.png (33.16 KiB) Viewed 2267 times

ChicagoGranny may be asking about the length of your centrals because the severity of your apnea isn't just how many events, but also how long each lasts, though that isn't taken into account in the the AHI score.

[ChicagoGranny]

If so, out of 12 events, 5 of them were below 15 seconds, the rest were between 20 and 30. So you're saying I can ignore the ones below 15 seconds?

I was thinking the other way around. If you see some real long ones, > 45 seconds or so, some digging into the data should be done.

In the Events tab, if you click on one of the CAs, your flow chart will jump to the event. You can then compare it to the examples Stom just posted. I would look at a couple of the longer CAs (~30 secs).

[ChicagoGranny]

Doctor told me "some people just don't tolerate CPAP"

is it true that CPAP just doesn't work for some people?

Those are two very different statements. Some people can't tolerate dusting the furniture. But, that doesn't mean the feather duster doesn't work.