Electrical impedance tomography data comparing near-apneic ventilation versus spontaneous breathing. (A) End-expiratory lung impedance versus baseline values change (delta end-expiratory lung impedance) during the study protocol. (B) Regional impedance distribution. Columns represent the relative lung impedance distribution, by layers, in spontaneous breathing versus near-apneic ventilation groups. §P < 0.05 for time 0 compared to baseline.