Questions re Early CPAP Results

[Somnos]

I am a CPAP newbie and have found this website to be helpful and instructive in dealing with my recent diagnosis and initiation of CPAP. By way of background, my wife has been telling me for years that I breathe irregularly at night, although she was not aware of prolonged periods of apnea. It is not infrequent that I would wake up with a headache that would last most of the day, and while I would say that I have some daytime fatigue, I tended not to be particularly sleepy in the daytime. This, plus the fact that I have had long-standing tendency to initial insomnia, led me to think that sleep apnea was not especially likely.

I had a home sleep study about one month ago which spanned two nights. I had 36 episodes of apnea/hypoxia per hour on one night and 37 per hour the next. My hemoglobin oxygen saturation hit a minimum of 68% on one night and 71% the next night.

Based on this, I was referred for a CPAP titration study which I completed. At the time I requested using a full face mask because I have a history of deviated septum which has been fixed but I have significant scar tissue which limits nasal airflow. The titration study showed that even at a maximum pressure (I slept for only three hours that night, and my pressures were not titrated only to 15 cm H2O), I was still having obstructive episodes. I also had some central apnea episodes on that study and on the home study as well. Despite frequent apneic episodes during the titration study, I was told that my hemoglobin oxygen saturation did not drop below 88%, which is somewhat reassuring. The recommendation was for auto CPAP with pressures of 5-20 cm H2O.

I obtained a ResMed Airsense Autoset on Saturday, July 25 and have been using it nightly since then. Although I have nothing to compare it to, I like the machine and also my mask (Airfit F 20 full facemask) which seems to fit well and I do not think I’m having substantial leaks. As might be expected, I’m having great difficulty getting used to falling asleep with something covering my mouth. I wouldn’t say that I feel anxious with it on, but have difficulty settling into sleep. Benadryl 25-50 mg did nothing to promote sleep, and I have occasionally utilized Ambien 2.5-5 mg which seems to be helpful. Each of the last two nights I awakened in the early morning hours to find my mask lying on the bed next to me, and Sleepyhead software indicates that I took it off for about one hour each night. But, in total, I have been able to keep the mask in place for most of the past five nights.

The Sleepyhead data, some of which I include below, looks pretty ugly to me and suggests that I am having a large number of continued episodes, both obstructive and central, despite the pressures ramping up to levels close to 20 for most of the nights. My understanding is that when CPAP is first initiated, it is not unusual to have a temporary increase in the number of central apnea episodes. However, it seems to me that I am having many such episodes and also having a large number of continued obstructive episodes. I had the ERP at zero on the first several nights, then reduced to a setting of 2 and, for the past two nights, set it at the maximum of 3. I find 3 a relatively comfortable setting in terms of tolerability but I’m not sure what, if any, effect this may be having on the whole picture. So, specific questions I have include:

1) assuming that CPAP becomes more tolerable and that I am not having large leaks, to what degree, if any, might I see further improvement in AHI in coming weeks or months?

2) While my total AHI is still (way) too high, is it the case that I am having an unusually large number of central apnea episodes?

3) As far as I know, the maximum pressure my machine can achieve is 20 cm H2O. Is this correct? Are there other machines that achieve higher pressures?

4) Any suggestions for modifications to settings, etc, that may help?

Thank you in advance for any insights, and thanks to all for contributing your knowledge/experience here!

[Pugsy]

Welcome to the forum.

You are going to need a machine that will go higher than 20 cm..and yes there are machines that will.
Bilevel machines will go to at least 25 and some will even go to 30.

Right now your biggest problem is the Obstructive Apnea events. I don't think you are having enough centrals to warrant concern.
Doctors usually won't raise an eyebrow about centrals until you start seeing over 5 per hour...every hour and all night long.

You need this machine...
https://www.resmed.com/us/en/consumer/p ... vauto.html
It can't really treat centrals (assuming that all of yours is real and not post arousal SWJ Sleep/Wake/Junk) but at this point that I doubt that all your centrals are real anyway. A few centrals here and there is normal and not cause for alarm..like sleep onset centrals or sleep stage transition centrals.

Your current machine starting point is too low but it quickly goes to maximum once you get to sleep...it's not going to work for you.

[Somnos]

Thank you Pugsy for your thoughts!

The machine link you posted shows that that machine can deliver up to 30 cm H2O of pressure. I do seem to tolerate 20 cm without great difficulty, so hopefully I would be able to tolerate even higher pressures. I will call CPAP.com, where I bought my machine one week ago, to see what they can do for me.

The only uncertainty I have at this point is whether the higher pressure alone will be adequate, or if I might need an ASV machine. If your belief is correct that the central apneas are not especially concerning in my data, looks like the higher pressure machine may suffice.

I have an appointment with a sleep specialist in about three weeks and I may wait for that, since I would rather not buy three machines in the space of about one month I’m going to try my machine while sleeping in a recliner rather than bed tonight, and I suspect that that may help.

Thank you once again.

[Sheriff Buford]

Maybe the place you bought the original machine will exchange for a bilevel machine. You'll need the doctor to change your prescription (get a copy of it). Also, your mask fit may start to act up at higher pressures, but don't worry about that now. Let us know how it goes and keep us updated.

Sheriff

[D.H.]

I agree. It seems that you're shooting up to 20 almost immediately. Also, new machine or not, there' no reason to start as low as 4 when your pressure is going that high. If the initial pressure bothers you, you can user the ramp. If not, forget the the ramp!

[Pugsy]

I agree. It seems that you're shooting up to 20 almost immediately. Also, new machine or not, there' no reason to start as low as 4 when your pressure is going that high. If the initial pressure bothers you, you can user the ramp. If not, forget the the ramp!

He's NOT using the ramp at all...that's the minimum setting at 4 cm...they way it came from the factory...4 min and max 20.

Yeah he obviously needs more minimum but he goes up so fast once he is asleep and the events starting happening it's kinda a moot point. Now if it went up and down wildly all night..yeah up the minimum.
He's going to need a minimum in excess of 15 to have any chance of getting those OAs reduced and starting out at 18 cm...probably is going to require ramp of some sort for a little while.

I have an appointment with a sleep specialist in about three weeks and I may wait for that, since I would rather not buy three machines in the space of about one month I’m going to try my machine while sleeping in a recliner rather than bed tonight, and I suspect that that may help.

Maybe the place you bought the original machine will exchange for a bilevel machine.

Apparently got it from cpap.com. I am not sure what they can do in this situation but I would be checking today.

The original culprit IMHO...the doctor who wrote the RX for APAP when it was already proven per the titration sleep study that pressures over 15 didn't get the job done. He should have been given a script for a bilevel auto....both for pressure needs and the potential central thing...after all bilevel is usually the first go to try for centrals when they are more numerous than we like to see.

I have an appointment with a sleep specialist in about three weeks and I may wait for that, since I would rather not buy three machines in the space of about one month I’m going to try my machine while sleeping in a recliner rather than bed tonight, and I suspect that that may help.

I don't blame you for not wanting to buy 3 machines especially at the prices those higher end machines will cost.
If you have been sleeping on your back you might be able to get by with less pressure if you can stay on your side...easier said than done sometimes but I know one person who needs 19 on his back and 9 when on his side and he worded real hard to figure out how to stay off his back. Doesn't always work for everyone but worth a try if you were on your back.
The recliner might also help...worth trying.

You should have been given a RX for an auto bilevel and I don't know why you weren't unless the doctor doesn't understand that not all bilevels have back up rates which are used for central apnea therapy.
The bilevel AirCurve 10 VAuto...is nothing more than an apap that can go higher than 20. It doesn't have a back up rate capability which is needed when people have a lot of centrals.
It's often prescribed though when centrals are numerous especially when the centrals seem to pop up only once a person starts on therapy because often with some time those will go away and not need treatment.
Right now from these reports though...not enough centrals to earn the ASV.

[Somnos]

I appreciate everyone’s insights.

The good news is that I spoke to CPAP.com and they will accept the machine for a full refund as long as it is returned within 30 days. I do not believe, from the way the representative answered the question, that their accepting the return is contingent on me obtaining another machine from them. But, I have been very happy with them in all ways and will likely purchase whatever machine I end up getting from them.

Just to clarify, the highest pressure achieved on the sleep study was 15 cm H2O. The recommendation of the sleep specialist based on the sleep study was APAP 5-20 cm H2O. I suppose their assumption was that going up to a pressure of 20 would likely treat the obstructive episodes. Obviously, it has not.

I was mistaken earlier: although there is a cutoff if the AirCurve 10 reaches 30 cm H2O, the therapeutic maximum it can reach is 25 cm. Therefore, without experimental results from another sleep study, I think I am now in the same position I was in previously: hoping that increasing the pressure, in this case to 25, will prevent obstructive episodes. CPAP.com tells me they do not have a machine that delivers more than 25 cm H2O of pressure. Also, while they have the AirCurve 10 Pugsy linked, they state that they no longer carry ASV machines. I’m not sure why that would be.

I am largely a back sleeper. Although I feel comfortable in general sleeping on my sides, for other medical reasons (TMI), I’m not able to reliably sleep on my side at all times. One night I successfully attempted to stay on my side as much as possible and the numbers the next day on SleepyHead were not fundamentally different.

The other potentially useful piece of information that I did not mention is that I used a Bluetooth oximeter, purchased from Amazon, the night before last and kept it on all night. It took readings every 30 seconds and transmitted them to my phone, but the app (Oxi Tracker) only displays a limited number of results, perhaps up to 40 or so. This means that I have no access to the data for most of the night. I was curious to see whether and to what degree my CPAP therapy, however limited so far, would prevent the major oxygen desaturations that were seen on the home sleep study. It can’t be good to desat to 68%!

[Stom]

I appreciate everyone’s insights.

The good news is that I spoke to CPAP.com and they will accept the machine for a full refund as long as it is returned within 30 days. I do not believe, from the way the representative answered the question, that their accepting the return is contingent on me obtaining another machine from them. But, I have been very happy with them in all ways and will likely purchase whatever machine I end up getting from them.

I'd check to see if the return is for *store credit* or for an actual refund. Regardless, I plan on buying my next mask from them because of the "return insurance" the specifically offer for free with the mask I'm interested in, and either type of credit is fine for me in that case since I'll want a different mask if the first one doesn't work out. But I haven't asked yet.

[Pugsy]

The machines that will go to 30 are very special machines used primarily for people with OSA and pretty severe COPD or some sort of neuromuscular disease.
Not auto adjusting at all...fixed bilevel machines used primarily for achieving a target lung volume when people have compromised respiratory systems.
Not what I would advise for you unless max of 25 isn't sufficient. There's a good chance that going to 25 will get the job done.
Even the ASV machines only go to 25.

[palerider]

It'd be worth turning off EPR, that'd be a 3cm pressure boost.

[Somnos]

There's a good chance that going to 25 will get the job done.
Even the ASV machines only go to 25.

Good to know. And no respiratory disease I'm aware of.

It'd be worth turning off EPR, that'd be a 3cm pressure boost.

I'll do so. For tonight on the recliner, though, I think I'll leave it at 3, so as to change only one variable at a time.
Thanks again!

[Somnos]

Sleeping in a recliner helped limit obstructions. Awakened at about 5AM, took mask off to get a drink of water, and must not have re-applied it as well, because had more leaks and more obstructions thereafter. Seeing fewer central apneas, which is reassuring to me. Will be ordering the AirCurve today.