File:Sucking chest wound mechanics.jpg

English: The mechanics of a sucking chest wound. Caption is "FIGURE 2.—Schematic showing of pathologic physiology of sucking chest wound. A. Entrance of air into chest on inspiration through wound in chest wall (a), the amount of air being directly proportional to the size of the opening as compared with the surface area of the open glottis. Collapse of lung on affected side (b), with passage of air out of affected bronchus. Entrance into bronchus of some air from collapsed lung (c), with passage to intact lung. Shift of mediastinum toward uninvolved side (d), hemothorax (e). B. Escape of air on expiration through sucking wound of chest wall (a). Expansion of collapsed lung (b). Passage of air from uninvolved side to lung on involved side, thence out trachea (c), producing the so-called pendular breathing. Shift of mediastinum to involved side (d). Hemothorax (e)."