不同肺复张策略对急性肺损伤大鼠肺保护作用的比较研究

Comparison of difference recruitment maneuver on lung protective effects in rat with acute lung injury

目的探讨不同肺复张策略对急性肺损伤大鼠肺保护作用的比较。方法清洁级SD大鼠40只，雌雄各半，随机分为四组，空白对照组（K组）、急性肺损伤组（Au对照组）、传统肺复张策略组（RM1组）、逐渐提高压力的肺复张策略组（RM2组）。后两组采用不同压力的控制性膨肺的肺复张策略。机械通气4h后，采集腹主动脉血样，行血气分析；采用酶联免疫吸附测定（ELIsA）法测大鼠BALF中肺表面活性物质相关蛋白A（SP—A）和凋亡因子（Fas）的浓度；取部分大鼠肺组织做病理学肺损伤评分。结果与K组比较，ALI组的Fas水平较高，SP—A水平降低，肺损伤评分升高；pH值降低，PaO2降低，PaCO2升高（P〈0．05）。与ALI组比较，RM1和RM2两组Fas水平较低，SP-A水平较高，肺损伤评分降低；pH值升高，PaO2较高，PaCO2降低（P〈0．05）。与RM1组比较，RM2组的Fas水平较低，SP—A水平较高，肺损伤评分降低；PaCO2降低（P〈0．05），pH和PaO2值差异无统计学意义（P〉0．05）。结论肺复张策略可以提高氧合，降低PaCO2，增强有效通气；可以增加肺内SP—A水平并减少Fas表达，减轻肺损伤，具有肺保护作用；逐渐提高压力的肺复张策略的肺保护效果优于传统肺复张策略。

Objective To compare the lung protective effects of difference recruitment maneuver in rat with acute lung injury （ALI）. Methods The ALl rat model were randomly divided into 4 groups （ n = 10 each） ：control group （K group）, the acute lung injury model group （ALl group）, conventional lung recruitment maneuvers group （RM1 group）, gradually increased pressure lung recruitment maneuvers group （RW group）. After four hours of mechanical ventilation,lung injury was evaluated by Smith lung injury score. Surfact ant associated protein A （SP-A） and Fas levels in bronchoalveolar lavage fluid （BALF） were measured by enzyme-linked immunosorbent assay （ELISA）, and blood samples were collected and blood gas analysis was performed. Results Compared with group K, serum Fas concentration and Smith lung injury score were increased, serum SP-A concentration,PaO2 was decreased and PaCO2 were increased in group ALI （P 〈 0.05）. Compared with group ALI, serum Fas concentration,Smith lung injury score, pH, PaCO2 were decreased and serum SP-A concentration, PaO2 was increased in group RM1 and RM2 （ P 〈0.05）. Compared with group RM1 ,serum Fas concentration, Smith lung injury score were decreased and serum SP-A concentration,PaO2 was increased in group RM2 （P 〈 0.05）. pH and PaCO2 showed no significant difference between two groups （P 〈0.05）. Conclusions Lung recruitment maneuvers has the effects of improving ventilation efficiency. It has decreasing serum Fas concentration and reducing the lung injury. The better effects are obtained the gradually increased pressure lung recruitment maneuvers than the Conventional lung recruitment maneuvers.