Isolated pulmonary blast injury in rats--a new model using the extracorporeal shock-wave lithotriptor

Blast injury to the lungs is one of the most overwhelming threats to survival following exposure to powerful explosions. The pathophysiology of blast injuries differs significantly from other forms of trauma. Using the extracorporeal shock-wave lithotriptor, originally designed for the noninvasive treatment of nephrolithiasis, we were able to produce isolated, typical pulmonary blast effects in rats. The immediate mortality was associated with bilateral pneumothorax and hemothorax. A nonlethal dose of shock waves caused intra-alveolar and intrabronchial hemorrhages and an immediate 2- to 3-fold increase in the lung weight. Additional marked increase in lung weight started 12 to 24 hours later, consistent with the clinical picture of delayed respiratory insufficiency which occurs after a latent period of 12 to 48 hours in many blast casualties. The use of air-containing vest as a protective measure completely prevented blast injury to the lungs.