体外膜肺氧合技术对兔失血性休克肺的保护作用

Function of extracorporeal membrane oxygenation technology in protecting uncontrolled hemorrhagic shock lung of rabbits

目的探索体外膜肺氧合（extracorporeal membrane oxygenation，ECMO）技术对兔失血性休克肺的保护作用。方法采用兔失血性休克模型（24只，雄性，生理年龄6～7月龄，体质量2～3 kg）；维持休克3 h后分为3组，未复苏为A组，单纯采用晶体＋输血复苏为B组，体外膜肺氧合联合全血和晶体复苏为C组。复苏2 h后分别观察各组血流动力学改变，行肺泡灌洗观察肺通透性，肺组织采取HE染色光镜下观察病理改变并评分；ELISA法检测肺组织髓过氧化酶变化；并进行统计分析。采用DNA断裂原位末端标记法发检测肺组织细胞凋亡情况以及采取Western blot方法观察半胱氨酸蛋白酶-3（Caspase-3）表达情况。结果血流动力学：C组的收缩压、舒张压以及平均动脉压较A组和B组均明显回升（P〈0.05，P〈0.01）。肺组织HE染色光镜下观察C组病变最轻，病理评分C组最轻（P〈0.05）。采用DNA断裂原位末端标记法发检测发现C组凋亡最轻（P〈0.05，P〈0.01）。Western blot检测结果显示A组Caspase-3表达最高，C组最轻。肺组织髓过氧化酶检测结果显示A组Caspase-3最高，C组最轻（P〈0.05）。肺灌洗考马斯亮蓝蛋白浓度检测结果显示A组蛋白浓度最高，C组最低（P〈0.05）。结论采取体外膜肺氧合联合全血和晶体复苏不仅有利于兔失血性休克延迟复血流动力学的改善，还能明显减轻兔失血性休克肺的病理损伤、肺组织髓过氧化物酶的表达、抑制细胞凋亡以及保护其肺通透性。

Objective To evaluate the protection of extracorporeal membrane oxygenation （ECMO） for hemorrhagic shock lung of rabbit model. Methods We established rabbit model with hemorrhagic shock lung （24 male rabbits, physical age ranging from 6 to 7 months, individual weight ranging from 2 to 3 kg）. The rabbits underwent shock condition for 3 h and divided into 3 groups randomly. The unresuscitated rabbits were labeled as group A. The rabbits with injection of crystal and blood transfusion were labeled as group B. The rabbits that took ECMO combined with whole blood and crystal resuscitation were labeled as group C. All groups were resuscitated for 2 h. Then, we observed the hemodynamic changes. The massive lung lavage was taken to observe the pulmonary permeability index. Histochemical staining （HE） was used to observe the pathologic changes of lung tissue and pathological scores were determined. ELISA was used to detect myeloperoxidase changes of lung tissue. TUNEL was used to detect the apoptosis of lung tissue cells. Western blotting was used to detect the expression of caspase 3. Results The systolic pressure, diastolic pressure and mean arterial pressure of group C all increased as compared to groups A and B （P〈0.05, P〈0.01）. HE staining results showed that group C had the lightest pathological changes and the lowest pathological score （P〈0.05）. The apoptosis was the lightest in group C and the heaviest in group A as shown by TUNEL （P〈0.05, P〈0.01）. Western blotting results revealed that caspase 3 expression was the highest in group C and the lowest in group A. ELISA results displayed that myeloperoxidase content was the lowest in group C and the highest in group A （P〈0.05）. Bradford staining results showed that protein concentration was the highest in group C and the lowest in group A （P〈0.05）.Conclusion ECMO combined with whole blood and crystal resuscitation improves hemodynamic parameters in rabbit model of uncontrolled hemorrhagic shock with delayed resuscitation, alleviates the pathological damages and myeloperoxidase expression, inhibits apoptosis and enhances pulmonary permeability of uncontrolled hemorrhagic shock lung.