肺保护性通气对急性呼吸窘迫综合征家兔肺外器官炎症反应的影响

Effects of protective ventilation on inflammatory response of extrapulmonary organs in acute respiratory distress syndrome rabbits

目的 研究肺保护性通气对急性呼吸窘迫综合征 (ARDS)肺外器官炎症反应的影响。方法 用生理盐水肺泡灌洗法复制ARDS家兔模型 ,分为 6组 (1)正常对照组 ;(2 )ARDS模型组 (ARDS) ;(3)小潮气量 (VT) +最佳呼气末正压 (PEEP)组 (LVBP) ;(4)常规VT+最佳PEEP组 (NVBP) ;(5 )小VT+高PEEP组 (LVHP) ;(6 )高VT+零PEEP组 (HVZP)。后 4组机械通气 4h后 ,用逆转录PCR法 (RT PCR)检测动物肝肠组织肿瘤坏死因子 (TNF)α和白介素 (IL) 10mRNA表达 ,酶联免疫吸附法 (ELISA)测定肝肠组织TNF α及IL 10浓度。结果 LVBP组肝组织TNF α和IL 10mRNA表达分别为 (42± 9)和 (2 5±10 ) ,与ARDS模型组相比较 ,差异无显著性 ,分别为 [(37± 7)和 (2 5± 4 ) ],但显著低于NVBP [分别(5 6± 7)和 (36± 8) ]、LVHP [(5 3± 10 )和 (35± 5 ) ]和HVZP组 [(70± 10 )和 (46± 5 ) ]。LVHP组TNF α和IL 10mRNA表达明显高于LVBP组 ,但明显低于HVZP组。LVBP组肝组织TNF α和IL 10浓度与ARDS组无明显差异 ,但显著低于NVBP、LVHP和HVZP组。HVZP组肝组织TNF α和IL 10浓度最高 ,不但高于LVBP组 ,也高于LVHP组。LVBP组的肠组织的TNF αmRNA表达为 (38± 11) ,与ARDS组比较无显著差异 ,但显著低于NVBP (5 1± 9)、LVHP (5 0± 11)

Objective To evaluate the influence of protective ventilation on the inflammatory response of extrapulmonary organs in acute respiratory distress syndrome (ARDS) rabbits.Methods The ARDS rabbit model was established by saline alveolar lavage. The rabbits were divided into six groups: (1)normal;(2) ARDS group;(3) low-volume (V T) with best end-expiratory pressure (PEEP) (LVBP);(4)normal-volume(V T) with best PEEP (NVBP); (5) low-volume with high PEEP (LVHP)(6) high-volume zero PEEP (HVZP); Tumor necrosis factor (TNF)-α and interleukin (IL)-10 levels in liver and intestine homogenates were measured by ELISA and their mRNA expression RT-PCR.Results In the LVBP group, the TNF-α mRNA expression in liver was(42±9), which was lower than NVBP (56±7), LVHP (53+10), and HVZP group (70±10). But there was no different between LVBP and ARDS groups. TNF-α mRNA expression in LVHP group was higher than LVBP group in liver tissue, but lower than HVZP group significantly.Compared with LVBP group (25±9), the IL-10 mRNA expression increased significantly in NVBP (36±8), LVHP (35±5), and HVZP group (46 ± 5). Compared with LVBP group, the TNF-αand IL-10 concentrations in liver were increased markedly in NVBP, LVHP, and HVZP. But there was no difference between LVBP and ARDS group in TNF-α and IL-10 concentration in liver. Live TNF-α and IL-10 concentration was highest in HVZP group, which was higher than LVBP and LVHP group. In the LVBP group, the TNF-α mRNA expression in intestine was (38±11), which was lower than NVBP(51±9), LVHP (50±11), and HVZP group (64±11). But there was no different between LVBP and ARDS groups. The intestine TNF-α mRNA expression in LVHP group was higher than LVBP group, but lower than HVZP group significantly. As compared with LVBP group, the TNF-α concentration of intestine in NVBP, LVHP, and HVZP were markedly increased. But there was no difference between LVBP and ARDS group in TNF-α concentration of intestine. TNF-α concentration in intestine tissue was highest in HVZP group. As compared with LVBP group (22±7), the IL-10 mRNA expression in intestine increased significantly in NVBP(32 ± 7), LVHP(32 ± 8), and HVZP group (41± 5). IL-10 concentration of liver tissue in LVBP group showed no difference compared with ARDS group, but increased significantly in NVBP, LVHP, and HVZP group. IL-10 concentration in intestine tissue was highest in HVZP groups. The concentration of MPO and MDA showed no difference between ARDS and LVBP group. But compared with LVBP groups, the concentration of MPO and MDA increased significantly in NVBP, LVHP, and HVZP group.Conclusion Protective ventilation strategy can down-regulate inflammator mediator expression in the liver and intestine of ARDS rabbits and may prevent the occurrence of multiple organ dysfunction syndrome.