Objective    To explore the dynamic response of rat chest wall to different blast waves and its relationship with the injury severity in closed chamber.     Methods    Different spherical explosives with different explosive energies equal to 80

200

400 or 600 mg TNT were used to produce blast waves to 4 groups of rats (n=10) respectively in a closed chamber. All rats were anesthetized and with their chest placed 11.5 cm from the detonator. A REDLAKE-HE high-speed camera was used to record the movement of chest wall and the over-pressure of blast wave. The rat injury were analyzed with adjusted severity of injury index (ASⅡ) and light and electron microscopy.     Results    Chest deformation

and the highest speed of chest wall inward were correlated with ASⅡ (r=0.967 78

P=0.032 22; r=0.968 81

P=0.031 19). Thoracic organs injury due to inward motion of chest wall was viscous damage by blast wave.     Conclusion    The movement of chest wall appears to be one of the major factors causing the thoracic injuries. The highest speed of chest wall inward is well correlated with ASⅡ

and is a reliable parameter to indicate the shock injury severity.