Fluctuating AHI

[purplemonkey17]

Hi everyone,

First time posting here,

I started cpap treatment on November 1st and it's been a difficult ride.. My AHI is constantly changing and my OA's as well as CA's seem to not make a difference no matter what pressure settings I try. My CA episodes are the worst though and feels like it's just at random how many episodes of those I get, though I average around 2.5-3 per hour/night. 

My initial sleep study revealed an AHI of 5.1 which is very mild (my sleep was extremely wonky for two weeks and I had the study within that time frame so I'm not sure if it would've affected my results at all) but nonetheless I was still prescribed a cpap. This was in March and because of my low results I denied it, but recently decided to give it a shot since I'm always feeling tired and foggy. Last night my AHI was higher than my sleep study results at 5.51 AHI. I'm not sure what to do at this point. I've attached my Oscar screenshots of the last three nights in the case that it might make sense to anyone, I wanted to post my sleephq link as well which shows all of my recorded nights in November but sadly unable to do that as I am a newer member.

Any help is appreciated, thank you for taking the time to read this!

[Deborah K.]

I suggest you raise your pressure settings to 8 to 13. Your median pressure is 7.5, 8.5,  and 8.3, so 8 is a good place to start.  You are bumping up against your highest pressure so you need some headroom; that's why you should change it to 13.

Again, welcome, and good luck with your new therapy!  

[purplemonkey17]

Hi Deborah,

Thank you for your suggestion, I'll give that a try tonight and let you know how it goes!

[purplemonkey17]

Hi Deborah,

Sadly results still around the same  

Maybe I'm just cursed to have bad AHI 

[ejbpesca]

My AHI bounces around.  It is usually under 5.0 and over 2.0.  After 18 years of CPAP, I'm still fiddling with pressure settings.  I bring up the min. to prevent apneas as opposed to my APAP machine hitting 20 after apneas.  It will be very interesting to see if a minimum pressure increase for you reduces your AHI.

I am once again gradually raising my Min. pressure in hopes of lowering AHI.

[SarcasticDave94]

When CA are involved, it likely will be a fluctuating thing. There's less consistency to them. Were the CA something that showed at high levels on the sleep study?

[paulag1955]

This is what I came here to say. Central apneas are entirely random. I can have an AHI of .71 one night and 4.71 the next night and it's all because of the central events. My obstructive events are usually about the same.

[Sleeprider]

Your apnea is a mix of centrals and obstructive events, with the obstruction showing clear signs of positional apnea clusters. https://www.apneaboard.com/wiki/index.ph...onal_Apnea Your charts show your lowest AHI was actually November 24, and the most recent chart on Nov 28 is nearly that good if we resolve the positional obstruction issue. November 24, your EPR was set to 2 which reduced the CA events compared to the other nights at EPR 3. Based on what I'm seeing, I think you should be minimum pressure 7.0, maximum 10 and EPR 2, and assess your pillows and sleep position for possible chin-tucking mechanisms which infrequently causes an increase in obstructive apnea clusters.

[paulag1955]

Centrals will be reduced the most by lowering or eliminating EPR, then seeing what that does to flow limits.

[purplemonkey17]

Thank you everyone for all of your input!

Ejbpesca - I was not prepared for all the trial and error there was going to be when starting treatment, guess it's just another lifelong job.  

Paulag1995 - My lowest CA was 0.65 for a single night (as opposed to the 2.0+ average), I don't know how that happened but still dreaming (to the best of my abilities) to get there again.

Dave - I actually don't know, my sleep doctor did not mentioned anything about CA to me or my doctor so I guess that wasn't a problem when I had my study.


Sleeprider - Interesting, thank you for your insight, maybe it is positional because closer to when I started treatment my settings were 4-8 (as per my prescription). My OA events averaged around 1 with the lowest being around .40. Obviously it didn't last which got me experimenting with pressures haha. I also struggled with high flow limitations which is why I turned on EPR in the first place (otherwise I'd keep it off if it means less CA). I will follow your instructions and adjust the pressure and EPR accordingly. The wiki you sent mentioned a soft cervical collar may help, I actually ordered one but then never used it because I still had high OA events even when forcing myself to sleep on my side, but apparently it can still happen when side sleeping, I'll try using it tonight.