构建一种简便可重复的大鼠胸外伤所致肺挫伤模型。

选取SD雄性大鼠40只，体重220~240 g，按随机数字表法分为A组（对照组，撞击能量0 J）、B组（撞击能量0.588 J）、C组（撞击能量0.98 J）、D组（撞击能量1.176 J）、E组（200 g，100 cm，撞击能量1.96 J）。制作简易装置，通过重物自由落体撞击SD大鼠右侧胸部建模。运用小动物CT影像学检查判断有无肋骨骨折及血气胸，并计算出肺挫伤比值比较不同撞击能量组肺部影像学差异，病理切片HE染色从微观层面评估肺部挫伤情况。

胸部CT提示，A、B组大鼠无明显骨折，C、D组各有单根和两根骨折1例，A、B、C及D组无明显血气胸。E组存活大鼠有3只发生2根肋骨骨折，1只发生3根肋骨骨折，另一只发生3根以上肋骨骨折（合并少量血胸）。各组肺挫伤比值差异具有统计学意义；肺挫伤肺组织处理后HE染色提示发生了病理改变。

成功构建了较为理想的SD大鼠肺挫伤动物模型，适合的撞击能量为1.176 J。

To establish a simple and repeatable rat model of pulmonary contusion induced by thoracic trauma.

A total of 40 male SD rats weighing 220-240 g were selected and randomly divided into five groups using a random number table: Group A (control group, impact energy: 0 J), Group B (impact energy: 0.588 J), Group C (impact energy: 0.98 J), Group D (impact energy: 1.176 J), and Group E (200 g, 100 cm, impact energy: 1.96 J). A simple device was made to model the SD rat’s right chest hit by a free fall of a heavy object. The CT imaging of small animals was used to determine the presence of rib fractures and hemopneumothorax. The ratios of pulmonary contusion were calculated to compare the differences in the lung imaging between the groups with different impact energy. HE staining of pathological sections was used to evaluate pulmonary contusion at the microscopic level.

Chest CT showed that there were no obvious fractures in Groups A and B; there were 1 case of single fracture and 1 case of two fractures in Groups C and D; there was no obvious hemopneumothorax in Groups A, B, C, and D. Among the surviving rats in Group E, three had two rib fractures, one had three rib fractures, and one had three or more rib fractures (complicated with a small amount of hemothorax). The ratios of pulmonary contusion were statistically different between the groups. After treatment of lung tissues of pulmonary contusion, HE staining suggested different pathological changes.

An ideal SD rat model of pulmonary contusion is successfully established, and the suitable impact energy is 1.176 J.