CPAP & ASV Apnea machine Questions Regarding Accuracy

[Jimsim]

CPAP & ASV Apnea machine Questions Regarding Accuracy
                                
I have complex sleep apnea with both central & obstructive features.  There is also Cheyne-Stokes respiration.  I have used both CPAP & ASV apnea machines.

One night while using my CPAP apnea machine I couldn’t fall asleep & lay awake for about 6 hours. During that time I didn’t notice any changes in my breathing.  No pauses, no slowing down or stopping of my breathing yet the reading on my apnea machine indicated that I had 29.6 apneas per hour. I know for sure I didn’t sleep so how can this be?  
CPAP & ASV Apne
There are other nights when I had between 40 and 50 apneas per hour, yet upon awakening, I felt I had a good sleep.

I am wondering if these apnea machines are really giving an accurate reading. Has anyone else had this experience?  

The reason I am asking this question is because my doctor has recommended that I buy an ASV apnea machine which costs around $5,600.00.  A lot of money for me.  I hate to spend this amount of money if I don’t really need it.

[SarcasticDave94]

To determine if you need ASV, you have to base the decision on your prior sleep study detailed report. You mention having Apnea, and Obstructive and Central. However you don't mention actual event count.

If the doctor is recommending ASV, then probably the centrals are needing addressed. Most doctors diminish CA as being less important than OA, and if this doctor sees need for ASV, possibly the Central is pretty high.

As for accuracy of CPAP, it depends on the details, which you don't mention. Get OSCAR charts from the top link. It's safe and gives lots of useful info.

One big area that affects sleep disruption and CPAP accuracy is leaks. Your mouth might be wide open all night, therefore therapy pressure is blowing and benefiting you none. Just an example. Or the mask might be leaking a lot, again causing accuracy issues. No sleep night will be identical but they can be similar.

[Jamesroelschlager]

I also experience a combination of Central Apnea and Obstructive Apnea that they labeled Complex Apnea.  My Central Apneas went from 16 events per hour during original sleep lab study to only 1-2 per hour once CPAP was initiated.  As a result the sleep doc discussed the ASV equipment cost and said I would not qualify for insurance paid device and I new they were several thousand.  Interestingly when I traveled to Arizona in an area of high altitude vs. Florida where I live, I experienced more Central sleep apneas.  This year in New Mexico for 1-week vacation I experienced a huge number of Central Apneas (25 Central per hour) with the machine also noting Cheyne-Stokes respiration. I was concerned enough about the Central Apneas that I spoke with my Dr.s nurse practitioner and she indicated I would still have trouble getting Medicare/BCBS to pay for an ASV machine if it only worsened in high altitude conditions when on vacation.  I decided to search for a used RESMED AIRCURVE 10 ASV machine and was fortunate and found one that was extremely reasonable at $150 with only 3600 service hours on the machine.

I have used it now for three nights and made adjustments to the settings based upon some of the guidelines offered at this Apnea Board.  Last night I had only .88 hypopnea per hour and no obstructive or central  apneas and I woke up feeling much more refreshed compared to the CPAP RESMED AIRSENSE 11, I was using this year.  I also recently purchased a sleep disorder book by Dr. Barry Krakow called “Life Saving Sleep: New Horizons in Mental Health Treatment” after consulting with him for a second opinion after my New Mexico experience with Central Apneas that was also helpful in deciding to give either a BIPAP or ASV machine a trial.  I am a psychologist and was impressed with the useful information and tips included in the sleep book and I had worked with many patients who failed with CPAP and many who gave up completely.  I myself always experienced the forced air sensation of CPAP when breathing in/out with the CPAP, even with the expiratory relief (EPR) adjustments, challenging for me.  The  book was helpful in exploring this issue and the Dr. indicated that he frequently shifted to prescribing BIPAP or ASV for most of his patients to offer more comfort and compliance.  Anyway I got long winded but if your Dr. is recommending ASV and you could locate one used as I did it maybe beneficial to try it.  Good luck.

[ejbpesca]

I am seeking to get a BiPAP or ASV machine after 19 years of APAP.  For me, my AHIs have not always matched how I feel after sleeping.  I am having trouble with APAP and would like to switch.

Your experience of lying awake and recording apneas could be misleading.

Posting an OSCAR report gathered from your machine's data via an SD card of a full sleeping session will give a clearer idea of how well your therapy is going.

If you are reading AHI of 40 - 50 that is severe apnea that is not being treated.  Could you post a recent OSCAR report?