(07-31-2024, 08:28 AM)SarcasticDave94 Wrote: DFWdude,

Just one possibility there in this OSCAR chart, last segment, maybe it's SWJ (Sleep Wake Junk) issue. The pattern can crop up because the CPAP user is transitioning frequently between sleep and wake breath control, mass confusion results and lots of events appear. These will show up on the bookends, beginning or ending of therapy sessions/segments, much like this.

(07-31-2024, 08:28 AM)SarcasticDave94 Wrote: "Not answering for Sleeprider, but typically a PS of 8 will increase Central Apnea, if there's no backup breath rate function. When I was on ASV, I could use PS range 3-15, because ASV uses backup rate.

By the way, Sleeptechmaster, you don't have any CPAP info filled in on you left panel user info. No CPAP but overflowing with input that's not ideal?"


Yes increase sleep apnea but it didn't look like he had a central issue to begin with that would be severely worsened. 
The asv backup rate doesn't compare directly to bipap backup rate. I'm actually watching a training now that talks about it. Asv backup rate varies in an attempt to control tidal volume to central events only. Bipap backup rate is constant to provide stable control to obstructive events- ipap for hypopnea and epap for apnea. 

Im currently testing a cpap on myself but it's only been a few days so I'm trying to figure out a good pressure. I think I might need ASV haha. I put the max pressure at 18 and AHI went up to 25 but when it was lower it was about 10. Now I'm testing a constant pressure of 12. 
I run titrations all the time with most cases resulting in optimal studies.

(07-31-2024, 08:30 AM)Sleeprider Wrote: PS at 8.0 will result in excessive CO2 washout and make central apnea problems much worse. This individual shows a normal I:E ratio and no flow limitation, so attempting to manipulate respiration timing or volume with unusually high PS would certainly be counter-productive.  Very high PS with a spontaneous triggered device has been tolerated by a very limited number of individuals attempting to treat very severe flow limitation, but generally these are the exception rather than the rule.  On the other hand, any suggestion I have made has been summarily dismissed as well, so I'm probably done here.


PS 8 is high but the 2 second inhale with a 8 second exhale would not seem natural. Large effort in expelling CO2 with resistance and the short quick inhale to limit oxygen. The recommended start pressure for some machines is 11/5 so that's a PS of 6. It should generally increase comfort and tolerability. The proper PS should be found to match his tital volume. 
Those Ti settings are from the resmed table listed to match the breathing rate of 20 and to aid patients who require longer exhale time. 

The recommended PS for COPD and obesity hypoventilation syndrome Is 8. 

(07-31-2024, 09:28 AM)SarcasticDave94 Wrote: Not getting into further discussion here, disrupting further the assistant DFWdude is seeking.

Wait? Who said anything about COPD for this OP?

DFWdude, you don't have COPD?

(07-31-2024, 08:30 AM)Sleeprider Wrote: PS at 8.0 will result in excessive CO2 washout and make central apnea problems much worse. This individual shows a normal I:E ratio and no flow limitation, so attempting to manipulate respiration timing or volume with unusually high PS would certainly be counter-productive.  Very high PS with a spontaneous triggered device has been tolerated by a very limited number of individuals attempting to treat very severe flow limitation, but generally these are the exception rather than the rule.  On the other hand, any suggestion I have made has been summarily dismissed as well, so I'm probably done here.

(07-31-2024, 09:34 AM)SarcasticDave94 Wrote: It's still not a good idea, unless you want to increase CA probability.

BTW what CPAP do you use?