Fig. 2

demonstrates the course of respiratory parameters during pressure-controlled ventilation (PCV; blue) and flow-controlled ventilation (FCV; red) since hospital admission. The grey area indicates prone position of the patient, the white area supine position. For FCV the (effective) alveolar pressures are calculated based on the measured resistance and the set flow according to Ohm’s law. a, peak inspiratory pressure (P_peak) and positive end-expiratory pressure (PEEP). b, driving pressure. c, ratio of arterial partial pressure of oxygen (paO₂) to fraction of inspired oxygen (FiO₂)