[Pressure] New user getting central apneas

[fstrife]

Dormeo, thank you for putting together those examples of arousal breathing!
Also, I have taken your suggestion and am trying to use the CPAP as I work on the computer today.

For last night (night #3) I turned off EPR (thanks SarcasticDave), reduced max pressure to 10, and changed to soft response mode.

This did result in less aerophagia and fewer awakenings, so it was a less frustrating night.
Resulting AHI was slightly higher (8.5), with an increase in hypopnea (from 1 to 2) offsetting a decrease in CA (from 7 to 6.3)
I feel a little better rested today.

I plan to increase max pressure to 13 for tonight.  I think I can sleep through the higher pressure at the beginning of the night, but have a hard time with it when I am less sleepy.  If the pressure keeps waking me up, I will probably reduce pressure or stop CPAP for the rest of the night.

   

[fstrife]

Given that my sleep study reports

•    Obstructive apneas (index): 0.1
  
•    Mixed Apneas (index): 0.0  
  
•    Central Apneas (index): 1.4
  
•    Hypopneas (index) : 6.6
  

, should I be questioning my doctor's diagnosis of mild obstructive sleep apnea?  Or does the hypopnea index of 6.6 usually inidicate obstructive hypopnea (vs central hypopnea)? 

The note from my doctor said:
"[redacted], MD has reviewed your most recent diagnostic sleep study, which showed results consistent with mild obstructive sleep apnea.

[redacted], MD recommends you to consider CPAP treatment. If you would like to proceed with CPAP treatment please contact the Sleep Center to schedule an home CPAP calibration study. Although continuous positive airway pressure (CPAP) is the preferred treatment, if you're not ready to start CPAP - an oral appliance could be an alternative option."

The sleep study report (post #2) said:
"Polysomnographic findings are consistent with Mild Obstructive Sleep Apnea Syndrome (RD/EI = 8 events per hour) without significant nocturnal desaturations."

[SarcasticDave94]

That was your diagnosic? Sure be my guest and question Dr. McQuack on the diagnosis. Those Hypopnea might have been Central based. Make a big list of all complaints and symptoms APAP isn't addressing. Doc this that the other isn't doing well. You may want to request a titration with ASV included.

[Dormeo]

Your home test would not have any way to distinguish between central and obstructive hypopneas.

It's interesting to compare your two charts. With settings of 7 - 10, and no EPR, your median pressure was actually higher than your median with settings of 7 - 13 and EPR of 3. ResMed machines are sensitive to flow limitations, and without the EPR, your FLs are more prevalent and severe. (You can see this from the numbers but more vividly by just eyeballing the two graphs.)

Your CAs may subside on their own as your body adapts to PAP. I think it's worth focusing for a week or two on getting you more comfortable and better able to sleep through the night without so many arousals and breaks.

For that reason, I'd suggest ignoring the CAs -- just for now. And that would leave me recommending that you turn EPR back on at 3 to reduce flow limitations, which may be preventing sounder sleep, and setting your min = max = 8, which will probably deal pretty well with obstruction, given your earlier chart and your sleep report. This will also keep you from experiencing pressure changes, which can disrupt sleep, and it will mean you are less likely to be bothered by aerophagia.

Whether you use these settings, or some other settings, I'd suggest that you stick with the settings you're trying out for several nights (unless they're awful). Sleep is naturally variable from one night to the next, so with several nights to go on, you'll be able to make better decisions about additional changes.

And although I'm recommending several changes all at once now, going forward see if you can make just one change at a time so that it'll be easier to sort out what consequences are associated with which changes.

[SarcasticDave94]

Some home tests do have an effort belt, if that was included maybe CA is acceptable in accuracy. Doesn't equal a lab test though IMO.

[Sleepster]

Obstructive apneas (index): 0.1
Central Apneas (index): 1.4
Hypopneas (index) : 6.6
should I be questioning my doctor's diagnosis of mild obstructive sleep apnea?

You add those numbers together and you get 8.1 for your AHI. Anything between 5 and 15 is considered mild sleep apnea. Be aware that that is just a diagnostic tool used by medical researchers. It doesn't mean the effects are mild. The effects could be quite debilitating.

Since you are suffering from both flow limitations and aerophagia, I concur that you should have EPR set to 3 to treat them. If the aerophagia is still a problem you may have to lower your pressure or switch to a bilevel machine (also known as a VAuto or a BiPAP).

But as I said before, you are switching your settings way too much. Set them and then leave them alone for several nights and see how you do.

[Sleeprider]

Whether his diagnosis was correct or not, the results showed a tendency to central apnea. With therapy, your CAI is now higher than than the diagnostic AHI, so concluding this is at least therapy onset central apnea is reasonable. Your doctor is going to observe your results over at least 1-month, and decide what comes next. It doesn't hurt to call and let him know your AHI is worse with therapy than without it, and it appears to be predominately central. That should clue him in to the next step, which should be a titration test, preferably one that moves from CPAP to BPAP to ASV. Most important to your doctor will be answering the question, How do you feel compared to before therapy? It's possible you will be heading to ASV therapy, but a bit premature at this point to make that conclusion.

[fstrife]

Wow.  Thanks everyone for reviewing my data and providing feedback/guidance.

I did take the advice of setting EPR back to 3.  


Pressure range is now 8 to 10.6.

OSCAR results appear to be good!  Also, I experienced very little aerophagia and I feel pretty good for only sleeping 5.5 hours.  I was still a little tired when I got up, but I got out of bed because I did not think I was sleepy enough to fall back asleep.  Along with CPAP, I am also trying to return to better sleep hygiene (e.g. staying out of bed when I am not sleeping).  I am used to needing 7.5 hours to feel rested, but of course, that was with poor breathing.

I know I've been changing settings, a lot!  I really do not intend to keep doing so, especially now that the settings are pretty tolerable and appear to be effective.  Keep in mind that my initial settings were just a generic starting point (not from a doctor).

Regarding my at home sleep test, it did measure respiratory effort via a thoracic band.  I have sent a message to the sleep clinic asking for more detailed results.  Even if they do provide more detailed information, I am not sure it will be much more useful that the OSCAR data.  The sleep test was done 18 months ago and I remember sleeping so little that I asked them if I could repeat the test (they did a quick check of the data and said they had enough).

Due to cost, I am hoping to not have to go back to a sleep doctor.  I purchased the CPAP with a prescription from my PCP (not the sleep doctor).  I went into this thinking that an APAP would handle my mild obstructive case with ease.  If I do need an ASV, ideally I would change machines before the 30 day return period is over.  I could also switch to better insurance coverage next year, but after reading about how difficult it is to prove ASV necessity, I may be better off with the cheaper insurance and paying out of pocket.  In any case, last night's results make me hopeful that APAP is sufficient.

I will continue practicing with the CPAP machine during the day today.  

   

[SarcasticDave94]

On machine changes, if you're using a doc to process through insurance, a script change will trigger a different level machine request at any time and it's not limited to 30 days. If approved all along the entire process, getting doc to request a test, see results, order ASV via new script, then you get the ASV.

[fstrife]

I guess an exchange to ASV within the 30 day return period is not really an option.  I would need a prescription and that would require seeing a sleep doctor and more studies/data/justification.

Anyway, I'm hopeful that my treatment is on the right course.  I'm feeling less tired and it looks the AirSense 10 AutoSet can reduce my AHI to below 5.