Events per hour question

[JDM]

Hi,
I’v been using my new AirSense 10 AutoSet nightly for about a month. Everything seems to be going fine. Better than expected actually. I contribute my smooth transition to the enormous amount of time spent researching topics on this site and many others prior to actually taking the plunge. There’s only thing bugging me. I’m not clear about the EPH average that appears on the display after usage.
In my case, I average approximately 3.0 EPH. I understand it means that I quit breathing (more then 10 sec) for an average of 3 times per hour. The part that I don’t understand is whether or not the machine corrected my apnea events, or how much it ramped up in an attempt to correct the problem? Clearly it had to be corrected at some point or I’d be dead now! It’s just confusing. It would seem that on average my machine would have to ramp up to at least 20 CM H20 during those 3 events in an attempt to correct my apnea right?
I tried to trick out the machine by purposely quitting my breathing just to see what it does. Haha, it was VERY difficult and yielded basically zero help in understanding how this thing works!
My machine is set to a prescription range of 8 - 20 CM H20.
My pressure average is 10.5
Doubt this is relevant, but my sleep study results were 36 events per hour prior to getting started on my auto cpap so I suppose it’s helping.

Thanks:)

[LSAT]

Prior to using the CPAP your events were 36 per hour. At the pressure you are at, the machine has eliminated most of your events and for one reason or another, it was not able to stop 3 per hour. I'd say it did a pretty good job. It's unrealistic to expect the machine to eliminate all events every night. If you want to further analyze your therapy, download the Oscar software. https://www.sleepfiles.com/OSCAR/

[Pugsy]

The Events per hour average shown on the machine are the events the machine wasn't able to prevent for whatever reason.
It's possible that the machine did increase the pressures as best it could in an effort to PREVENT the event but if you are thinking that the machine actually increases the pressure DURING the apnea event....wrong assumption.

Number one...not all apnea events can be fixed or prevented with more pressure...central apneas being one because more pressure won't fix those because the airway is already open.

Number two...none of the auto adjusting machines will do ANYTHING at all DURING the airway collapse and try to blow the airway open. They can't generate that much pressure so they don't even try. During an airway collapse they just sit by and twiddle their little thumbs and then when the airway opens back up they re-evaluate what has happened and then decided if they want to increase the pressure a little more to better PREVENT that from happening again.

It's all about preventing the collapse in the first place and not blowing the airway open when it happens.

It would seem that on average my machine would have to ramp up to at least 20 CM H20 during those 3 events in an attempt to correct my apnea right?

No...not correct. For the reason explained above...it won't do it...even for an obstructive apnea it does nothing during the collapse and if it is a central apnea it doesn't even get factored in for the need to potentially increase the pressure to prevent further events.
Central apneas aren't fixable or preventable with more pressure and in fact in some cases can make them worse.

Sounds like you were expecting the machine to just blow open the airway when it collapses...it doesn't work that way.
Common error in thinking though. You aren't the first and won't be the last.

[ChicagoGranny]

The part that I don’t understand is whether or not the machine corrected my apnea events, or how much it ramped up in an attempt to correct the problem? Clearly it had to be corrected at some point or I’d be dead now!

Then why didn't you die when --->

but my sleep study results were 36 events per hour prior to getting started on my auto cpa

BTW, 3.0 AHI is good for a beginner. Some of that AHI might even be SWJ - sleep/wake/junk - events that are recorded when you are awake.

[khauser]

Clearly it had to be corrected at some point or I’d be dead now!

This is a fascinating statement. It suggests there was no apnea before you got the machine, else as you say you'd be dead.

The truth is that apnea is not an instant killer. It wakes you up, not all the way, but enough to disturb your sleep. As this continues you lose a lot of sleep, and worse it interferes with your ability to have normal sleep cycles, so you may not get much or any restorative sleep. That's why along with snoring the common complaint is being tired all the time.

The constant disruption to your sleep causes medical issues over time that slowly but surely decrease your overall health and increase your chances of death.

The machine is designed to REDUCE this so you can get restorative sleep. Others have already explained how the machine can't make you breathe. It is not an invasive ventilator. If it could pump air in your lungs your mask would simply lose air ... people that need ventilation have a breathing tube inserted ... that tube SEALS the airway which allows the machine to breathe for you.

Good on you for learning! Just remember your early (or even later) preconceived notions on what is happening may not match reality, so be prepared to change your point of view.

[JDM]

Alrighty then, learning has definitely occurred here:) That clears up my misunderstandings on this topic. Thank you all for the speedy replies.

[JDM]

BTW; I’m a pilot, so therefore my career is dependent on this treatment to retain my medical certificate. It’s also the reason I’m so determined to get low numbers. I was very reluctant to get tested for a long time because of my career. Kept thinking that I could exercise my way out of this. No luck. Finally had to throw in the towel and get help. Hopefully it solves my problems. Thanks again

[khauser]

BTW; I’m a pilot, so therefore my career is dependent on this treatment to retain my medical certificate. It’s also the reason I’m so determined to get low numbers. I was very reluctant to get tested for a long time because of my career. Kept thinking that I could exercise my way out of this. No luck. Finally had to throw in the towel and get help. Hopefully it solves my problems. Thanks again

I am very glad that you took the step, both for yourself and those in your plane! You don't say what kind of pilot you are, but I know a typical commercial flight has to areas where mental focus is enough to keep you alert, with a space in between that is just non-challenging enough to let a sleep deprived person fall asleep. You don't want your copilot that freaked out, LOL

I've never dealt with medical certificates (not a pilot, just play one on an occasional simulator run) ... do you know if further medicals will include sleep studies? I would doubt that, and instead they will want to know you are using the machine. But sleep apnea can raise other problems that are troubling for a medical certificate. Obesity, blood pressure and type 2 diabetes are real risks. Any of those can imperil your medical (I know diabetes has recently been accepted for pilots as long as it is well controlled...)

Stay healthy and keep the shiny side up!

[Pugsy]

BTW; I’m a pilot, so therefore my career is dependent on this treatment to retain my medical certificate. It’s also the reason I’m so determined to get low numbers.

I thoroughly understand and don't blame you one bit. If it eases your mind....your 3 events per hour average is well within acceptable limits to not cause you you to have a problem with certification. I am pretty sure that they will be using the usual medical guideline of 5 per hour as a flagging marker. You might call your FAA certifying physician just to make sure.

Your numbers will likely also fall a bit just with some time. It's very common for new people to this therapy to have some false positive or awake event flagging happening because the machine doesn't know if you are asleep or not. It only measures air flow.
Quit trying to fool the machine into doing something by holding your breath....it very likely is causing a false positive flag of some sort and elevating your numbers.

When you have time and maybe want to dig deeper and learn more about what the machine can show you give OSCAR software a try.
There's a lot more in there than just numbers.
OSCAR https://www.sleepfiles.com/OSCAR/
http://www.apneaboard.com/wiki/index.ph ... stallation
http://www.apneaboard.com/wiki/index.ph ... rpretation

[Miss Emerita]

JDM, you've done your long-term health -- not to mention your piloting -- a huge favor by getting your AHI down from 36 to 3. Congratulations!

Two things you didn't mention. Do you think you're sleeping more soundly? And do you feel more rested during the day?

[JDM]

do you know if further medicals will include sleep studies? I would doubt that, and instead they will want to know you are using the machine. But sleep apnea can raise other problems that are troubling for a medical certificate. Obesity, blood pressure and type 2 diabetes are real risks.

Shouldn’t have to do more sleep studies, just required to provide data to prove I’m in compliance. The other parameters are checked every 6 months, with EKG yearly. All that stuff has been perfect in the past.

If it eases your mind....your 3 events per hour average is well within acceptable limits to not cause you you to have a problem with certification. I am pretty sure that they will be using the usual medical guideline of 5 per hour as a flagging marker.

My average is 3.0 but I’ve had nights as high as 5.4 and a low of 1.2. I’ll definitely look into the Oscar software! Thanks!!

JDM, you've done your long-term health -- not to mention your piloting -- a huge favor by getting your AHI down from 36 to 3. Congratulations! Two things you didn't mention. Do you think you're sleeping more soundly? And do you feel more rested during the day?

Thank you! I’m very fortunate the numbers are looking much better. I definitely sleep more soundly in regards to not waking up out of breath. I used to wake up gasping for air occasionally during the night. It didn’t happen every night but enough to frighten me. There were a few times that I was so concerned about suffocation that I was fearful of even falling back asleep and therefore elected to wake up early. That hasn’t happened at all since I started on the machine. There’s been a few days that I felt amazingly great and mentally sharp. I certainly contribute those days to the lower numbers. Most days however are pretty normal with not much notable difference. I never seemed to suffer from excessive tiredness during the day. Maybe a little after lunch, but certainly not while flying. For some reason I’ve always been able remain alert while flying, or driving.

[khauser]

My average is 3.0 but I’ve had nights as high as 5.4 and a low of 1.2. I’ll definitely look into the Oscar software! Thanks!!

5.4 is a little high, but since it is rare it's not a problem (many people would offer much to get to that point!)

More importantly you are feeling better, which is AWESOME!

I never seemed to suffer from excessive tiredness during the day. Maybe a little after lunch, but certainly not while flying. For some reason I’ve always been able remain alert while flying, or driving.

Lucky. There's been a few drives in my past where I have no recollection of parts, and a few times I know I was nodding off. I am lucky I found the issue!

[Pugsy]

I don't worry about these sort of high numbers (like the AHI of 5.4) when it comes to newbies and the overall average is lower.
This is why I suggest software evaluation...for all we know that higher night was at the beginning of therapy and there was a greater likelihood of trouble falling asleep and the bulk of the AHI was nothing more than a lot of SWJ getting flagged while awake.

Often newbies fixate on the numbers and worry needlessly about this sort of stuff when it really isn't a reflection of the therapy but more a reflection of poor sleep in general just from the newness of having to try to sleep with a mask on and having air blown up your nose.

When doctors evaluate the AHI numbers....pretty much all they look at is the long term average AHI. They don't go nit picking night by night detailed data unless that long term average is out of line. Doctors are also aware that for newbies sometimes it just takes a while for the body and the brain to adjust and they won't panic over a random "bad" night anyway.