An ultrastructure study on lung edema caused by severe brain injury

Objective To study the ultrastructure alterations in lung edema caused by severe brain injury.Methods Marmarou′s brain injury rat model was developed.The pulmonary water content in different groups was measured.The lung tissues were examined by optic microscopy (OM) and eletron microscopy(EM).Results The pulmonary water contents in severe brain injury groups were higher than those control groups.In the severe brain injury groups,the blood capillaries were dilatatied and congested,the lung alveoli were edema fous as observed by OM.The capillary endothelial cells and the alveolar epithelial cells were degeneratied and necrotic,and the structure of respiratory membrane was damaged as seen by EM.Conclusions In severe brain injury the lung alveolis and the blood capillaries are damaged, which is the anatomical foundation of neurogenic pulmonary edema.