03-27-2014, 10:22 AM
(This post was last modified: 03-27-2014, 02:49 PM by justMongo.)
I run my S9 VPAP Auto in spontaneous mode (S mode.)
In S mode, it operates between two set pressures -- IPAP and EPAP.
That is the mode I was prescribed.
There is a setting in S mode called Easy Breathe.
Let's call that EB. With EB turned on the rise time, for the transition to IPAP pressure is grayed out. With EB off, the rise time can be set. It defaults to 300 msecs.
What's interesting is -- with EB off, the FOT algorithm is off; and it does not differentiated between obstructive and central apnea. Also, the snore index and flow limitation are not recorded.
Last night, with EB on, I slept 7.5 hours; had an AHI of 1.8 and had one 10 second clear airway event scored as a central.
There was significant snoring; and flow limitation. Flow limitation is based upon the inhalation waveform. Rounded is good, flat-top is scored as obstruction a flow limitation.
Taking a look at the fine flow data, the snoring appears to be during exhalation when the machine has switched to EPAP pressure.
I wonder if bumping up the EPAP pressure a bit would help that?
I think I might bump it up by 0.4 cm-H2O tonight and test the hypothesis.
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I too was prescribed bilevel CPAP. I recently tried using auto mode to reduce the average pressure and the leakage. The machine lowered my average pressure and my leakage was somewhat better but my AHI went up significantly. Had a lot of hypopnea and increased apnea events. Of course, with my antique machine, it does not differentiate clear airway events from obstructive events. Went back to my original prescription of 20 IPAP, 16 EPAP and my AHI is much better and the leaks are reasonable (less than 24 l/min).
I too have (as you know) an older machine that can't 'see' CAs. I too switched to 'auto' mode, but with a much different result.
Originally, in 'S' mode, EPAP was '12', and IPAP was '18'. And I lived with that for a number of years, using a nasal mask strapped on tight, and lived with random (many to most nights) mouth hissing - to the point of having a sore mouth that spicy food (Taco Bell level) burned.
Switching to wide open Auto mode (which can only raise/lower both modes, "PS" doesn't change) with a Pressure Support of '6', my IPAP dropped down to around 12 to 14. Currently, I have IPAP at '6.4' and PS at '6.6' (gives an IPAP of '13'), and most nights max pressure stays around 13-14 with somewhat random hops up to '18' 2-3 times weekly. My AHI last night was '2.0', and my 95% leak rate was '10'LPM. At this point, this is also using a FFM only, and I am not seeing any reason to change any settings.
*I* am not a DOCTOR or any type of Health Care Professional. My thoughts/suggestions/ideas are strictly only my opinions.
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