Fig. 3.

Tidal impedance variation as an estimate of tidal volume, relative to baseline (indicated by the dotted line) a) box plots represents the interquartile range with the median, and the whiskers represent the range for each setting b) individual levels of tidal impedance variation per setting. This figure shows whether a specific CPAP/BiPAP settings decreases (<1) or increases (>1) estimated tidal volume in comparison with baseline and enables comparison of estimated tidal volume between different CPAP/BiPAP settings.