Fig. 2From: Effect of nocturnal EPAP titration to abolish tidal expiratory flow limitation in COPD patients with chronic hypercapnia: a randomized, cross-over pilot studyRepresentative pressure and PtcCO2 tracings for the EFLT-abolishing-EPAP (black) and the fixed-EPAP nights (grey). During the fixed-EPAP night, EPAP and IPAP were kept constant at the prescribed values (horizontal dashed lines)Back to article page