Respironics’s   C-flex works perfectly in Auto mode, ResMed’s EPR does not work in Auto mode. EPR works only in “CPAP” mode or “constant pressure” mode.

C-flex has the ability to decrease pressure at the first gush of each breath. The decrease is not a long one as this happens only for a couple of milliseconds before breathing returns back to the prescribed pressure.  EPR is little different because it keeps the pressure low through out exhalation.

C-Flex reduces the pressure that is relative to an individual’s exhalation strength and in relation to the machine’s pressure setting. EPR reduces the pressure by 1, 2, or 3-cm. of H2O pressure depending on the setting the CPAP is set for. This is why EPR is not much different then being placed in a BIPAP mode in the way it feels. The only difference is EPR has a slower flow change behind it, by doing it a little slower there is less of a ventilator effect like BIPAP.

EPR has an Event Detection Circuit system that allows the unit to stop when disordered breathing takes place during sleep. It only resumes when it detects normal breathing again. C-flex on the other hand is said to have a short duration that it has no Negative effect on sleep disordered breathing occurrences and doesn’t really have the need to discontinue.

 A nice thing about EPR is Unlike C-flex, EPR can be limited to ramp mode only.