Side sleeper vs. Back sleeper readings

[Bob Cali]

I have central sleep apnea. I have a ResMed 10 ASV machine and a ResMed AirTouch F20 mask. I am strictly a side sleeper. I had to sleep on my back only for the past three + weeks and my average AHI reading was 3.8. Now I am able to sleep on my side and the past 2 nights my AHI reading was 0.11. My average over past 6 months prior to having to sleep on my back was 0.13. I am back to normal readings for side sleeping. My question is why is sleeping on my back so much higher? Soon, I will again have to sleep on my back for 3 + weeks and am uncomfortable knowing my readings sleeping on my back are higher, and seems I wake up often as compared to when I sleep on my side. My mask readings remain the same.

Thanks for your responses and enjoy your day.

[G. Szabo]

 When you are on your back, (i) your tongue moves backward, blocking your inhalation, and (ii)  your soft palatal prolapses more quickly into the nasopharynx, posing resistance during exhalatio

[OpalRose]

You may be experiencing what we call "Positional Apnea" or "chin tucking."
If your head tilts forward into your chest, you will effectively cut off your air, and no amount of air pressure can blast through that. Of course, without seeing a OSCAR chart, I'm just guessing.

What type pillow do you use? One pillow vs. two is better. Also try to avoid a too tall pillow or wedge that could cause your head to tilt forward.

Is the increase in Apnea events Central or Obstructive? Again, post a couple charts, preferably one when you know you were on your back and one when on your side.

[mawaw1992]

For most people with "Positional Apnea", chin tucking is the problem and a soft cervical collar remedies the problem. But in my case, for 2 1/2 years I wore a collar that prevented me from having clusters of OA's. I had a average AHI of 0.9. Then all of a sudden one night, just like you flipped a light switch, my AHI started going up to where I am now averaging 3.52 for the last 6 months. Nothing had changed about my sleep. Thought my collar might had got too soft over the years and purchased a new one just like it. Even lowered my pillow. Nothing seemed to help. The only thing I can figure that has happen is that something had changed in my airway allowing my tongue to fall further back causing a blockage of my breathing. I recorded myself sleeping with a camera and compared the timeline of it to Oscar and sure enough, as long as I was on my side I had no apneas, but once I changed to my back the problem started. I also noticed that during the apneas that my chin was staying above the collar, so I knew it was doing its job. Now I have been experimenting with different things to try and keep me on my side.

[PaulaO2]

First, how did you think your back sleeping nights went? Did you wake up more tired? Did you wake up often? Or was it no different than side sleeping nights?

Second, an AHI of anything less than 5 is good. So unless you felt bad and unrested with the "higher" AHI, there's no worries.

Third, what were the events in those higher nights? Were there an increase in obstructive events or central?

[Bob Cali]

I have central sleep apnea. My average past year is 0.49 with a 2.30 average in Feb. while having to sleep on back entire month.