Experimental study on the establishment of rat pulmonary blast injury model using simple T-pipe / 医学研究生学报

ABSTRACT

Objective At present, the model of pulmonary blast injury is characterized by complexity, a certain degree of safety risks,and difficulty in obtaining the materials.This article aimed to establish a simple, safe and reusable primary pulmonary blast injury model in rats. Methods A total of 16 SD rats were randomly divided into control group and pulmonary blast injury group. In rats of control group, only ketamine(120 mg/kg)was injected intraperitoneally and hair was removed from chest.In pulmonary blast injury group,after the rats were fully anesthetized and depilated on chest,they were placed in a reducing T-pipe with only chest fully exposed,and the pneumatic simulated blasting device was adjusted to 0.4 Mpa.Taking locations about 2.5 cm from the intersection points of the median line of the sternum with left and right anterior axillary lines as targets,explosion were carried out respectively,fol-lowing the sequence of right chest 2 min prior to left chest.Lung pathology,lung water content,arterial blood gas analysis, and inter-leukin-6(IL-6)changes were observed. Results No obvious dam-age was found as to the appearance of chest in all rats after blast inju-ry.Transient purpura appeared in 37.5%(3/8)of the rats within 5 min after injury and disappeared within 1 h.On the spot,62.5%(5/8)of the rats presented 10-20 s of brief apnea and gradually recov-ered 6 h later.The lung tissue W/D,serum IL-6 level and lung tissue IL-6 level in pulmonary blast injury group were significantly greater than those in control group[(4.97±0.37)vs(4.62±0.07),(68.13± 59.40)vs(16.27 ±5.08)pg/mL,(487.04 ±30.57)vs(172.74 ±35.02)pg/mL],representing statistically significant difference(P<0.05).PaO2level in pulmonary blast injury group was significantly lower than that of control group,and the difference was statistically significant(P<0.05).After pulmonary blast injury, punctate and flaky hemorrhages were observed in the lesions of lung tissues,showing red hepatic changes.Lung interstitium was obviously thickened and alveoli collapsed under microscope.Erythrocytes and edema fluid in lung interstitium and alveoli exuded.Gas embolism in intersti-tial blood vessels was observed under microscope. Conclusion The lungs of rats after blast through simple T-pipe is typical of prima-ry pulmonary blast injury in pathological and pathophysiological manifestations, which proves the convenience and reliability of the modeling method.