Fig. 2. Individual variations in Pao2/Fio2ratio for 11 of 12 patients after mechanical ventilation with pressure support ventilation (PSV; A ) and with neurally adjusted ventilatory assist (NAVA; B ). The horizontal bars represent the mean values. The unbroken line indicates NAVA then PSV; the dashed line indicates PSV then NAVA. Fio2= inspired oxygen fraction; Pao2= partial pressure of arterial oxygen.