Pressure vs AHI

wb9tpg · Post by **wb9tpg** » Mon Aug 29, 2005 7:50 am

First, I want to than Derek the myEncore software. It's great and it's helping me a great deal see whats happening. I'm was running in APAP mode with pressure set from 8 to 12; my official prescription was for CPAP at 8 and then increased to 12 after my second study (they said they only looked at me for 15 minutes at that pressure).

I've been watching my numbers for a little over a week now and my AHI was around 7 to 8 mosts nights (much worse one night after one small glass of wine). I looked at the AHI vs pressure graph and found 90% the aphneas were occuring at pressures of 11 or 12. The graph was almost exponential with virtually none at 8 to 10. Last night I changed the APAP pressure to run from 8 to 10; I know its only one nights data but I only had 5 OSAs the entire night and my AHI was 0.7 (a 10x improvement). The refreshed feeling is back too!

I also noticed my Snore Index vs pressure peaks at 10 and did have more snores last night. I'm running CFLEX at 2 now but want to take it down to 1 and watch myself for a week before tweaking further.

Thanks again

Titrator · Post by **Titrator** » Mon Aug 29, 2005 9:59 am

Hi Gary,

Where did you have your sleep study done? I live in Frankfort and am curious about local labs.

Ted

wb9tpg · Post by **wb9tpg** » Mon Aug 29, 2005 11:32 am

I had it done at the St Joseph Sleep Wellness Center. They're actually very nice and have excellent facilities and staff.

Titrator · Post by **Titrator** » Mon Aug 29, 2005 11:55 am

Don't forget,

Dr Barbara Philips is at Good Samariten Hospital in Lexintgon. She is the best by far.

WAFlowers · Post by **WAFlowers** » Mon Aug 29, 2005 6:12 pm

Sometimes higher pressures can cause central apeneic events (CSA). This might be what is happening to you.

Regardless, the pressure range which gives you the best results is what you should use. If you are getting better results (10X ) with a lower pressure, go with it!

I was also titrated at 8. The lab tried 9 and 10 buy found I had more events at those pressures. Since getting a 420e I've verified that the higher pressures cause more events for me, all reported as "apneas with cardiac oscillations" (i.e. central events). I've found that a range of 6.5-8.5 works quite well for me. I spend most of the night at the lower end of the range (my 90% is at 7) but occasionally rise to 8.5 for a short while every now and then. If I try and go below 6.5 I get increasing snores.

My range is so tight that I could probably do without an auto, but on those nights when something unusual happens (like the pint of Guinness I just had at dinner) it sure is nice to have a machine that will compensate!