Fig. 4.
(Upper) Column chart showing the percentage of optical field affected by the different histopathologic lesions in all the experimental animals. (Lower) Percentages of optical field with vascular congestion (A), inflammatory infiltrates (B), alveolar collapse/atelectasis (C), and septal dilations/ruptures (D) as a function of experimental positive end-expiratory pressure (PEEP) groups. Significant statistical differences are indicated by black circles (zero end-expiratory pressure), white circles (4 cm H2O), section signs (§) (7 cm H2O), and white triangles (11 cm H2O).