Interaction plot between V
, PEEP, and EELV
. VT, PEEP, and EELVBase were classified as high or low, as a function of their relationship with their median value. The following cut-off values were identified: VT 170 mL; PEEP 10 cm H2O; EELVBase = 157 mL. Bars are mean values, and error bars, standard deviations. Bias, mean difference between EELVWI-WO and EELVCT in each subgroup; EELVBase, end-expiratory lung volume at baseline (ARDS onset, PEEP 0); EELVWI-WO, end-expiratory lung volume assessed with the nitrogen washin-washout technique; EELVCT, end-expiratory lung volume assessed by computed tomography; PEEP, positive end-expiratory pressure; VT, tidal volume.