Figure 4

Changes in end-expiratory lung volume (∆EELV), distribution of ∆EELV and center of ventilation (COV) during high-flow tracheal (HFT) oxygen and modified HFT. Compared with the HFT and T-piece, the modified HFT induced significant global ∆EELV (A). ∆EELV was mainly distributed to the middle region of interest (B). In the normal lung model, there was no significant difference in COV among the three treatments (p = 0.357), but in the injured lung model, a significantly higher COV was found via the modified HFT compared with T-piece (p = 0.018) (C). Data are presented as means and standard deviations, and p values in pairwise comparisons are shown.