Fig. 3.— Automatic reaction from the auto-adjusting positive airway pressure (APAP) system when submitted to repetitive obstructive apnoeas. For each APAP system (a) GK 418P, b) Autoset®T, c) PV10i, d) REMstarAuto®, e) SomnoSmart®), the measured airflow and the mask pressure (Pm) during a period of 15 min are plotted.