Fig. 5. Samples of electrical impedance tomography tidal images. Sample recordings of the ventilation distribution at baseline (AWAKE) and at the end of general anesthesia (END); each of the same patient per group. Green  pixels indicate no impedance change, yellow  through red  indicate small through large changes. COV = center of ventilation; PCV = pressure-controlled ventilation; PSV = pressure support ventilation; SB = spontaneous breathing.