Influence of Impact Velocity and Chest Compression on Experimental Pulmonary Injury Severity in Rabbits

Abstract

The effect of impact velocity and displacement on pulmonary injury in rabbits was investigated by producing a series of nonpenetrating anteroposterior sternal impacts involving velocities of 5 to 18 m/s and displacements of 2 to 45 mm. Contusion of the bronchial region was dominant at impact velocities below 6 m/s and displacements above 20 mm; contusion of the alveolar region was dominant at impact velocities above 15 m/s and displacements above 2 mm. When impact velocity and displacement were high, both bronchial and alveolar regions were injured. Pulmonary injury severity, expressed as a severity index adopted from the Abbreviated Injury Scale 1976 (AIS), correlated well with impact displacement at a given velocity but poorly with the peak reactive force, impulse transfer, peak esophageal pressure, or the amount of available energy.