DW-3000呼吸机所致老年大鼠急性肺损伤模型的建立

摘要

目的 建立DW-3000呼吸机所致老年大鼠急性肺损伤的动物模型.方法 将20只健康老年雄性SD( Sprague Dawley,SD)大鼠随机分为2组(A组为致伤组,B组为对照组),实施麻醉和气管术切开后,吸入空气进行机械通气,通气时间4h.A组大潮气量通气(30mL/kg),B组小潮气量通气( 8mL/kg).根据动脉血气结果计算氧合指数、肺系数.测定支气管肺泡灌洗液( BALF)中IL-1β、IL-8含量及肺组织匀浆中丙二醛(MDA)总抗氧化能力(T-AOC)水平.观察肺组织病理学改变.结果 A组大鼠氧合指数较B组显著下降,肺系数较B组显著增高.A组大鼠BALF中IL-1β、IL-8[( 123.4±7.31) ng/L,(68.10±10.20)ng/L]含量较B组[(54.70±8.04)ng/L,( 37.70±7.10) ng/L]显著增高.A组大鼠肺组织匀浆中MDA水平较B组显著增高,T-AOC水平较B组显著下降.病理学结果,A组大鼠肺组织中可见较多的炎性细胞浸润和肺泡壁结构的破坏.结论 DW-3000呼吸机大潮气量通气4h后,能够造成老年大鼠的急性肺损伤.%Objective To establish a model of DW-3000 ventilator-induced acute lung injury in aged rats. Methods Twenty healthy aged male Sprague-Dawley rats were randomly divided into two groups. After anesthesia and tracheotomy was performed, rats received mechanical ventilation with air for 4 hours. Group A was control group (Large tidal volume 30mL/kg), group B was injured group (Small tidal volume 8mL/kg). After arterial blood gas was measured, oxygenation index was calculated. Lung coefficient was measured. Interleukin-lp and interleukin-S levels in bronchoalveolar lavage fluid (BALF). malondialdehyde (MDA), total antioxidant capacity (T-AOC) levels in the lung were assayed respectively. Lung histopathology was assessed between two groups. Results Oxygenation index decreased significantly in group A than B, but lung coefficient increased obviously. The levels of interleukin-lp and interleukin-8 increased in group A[(123.4±7.31)ng/L, (68.10±10.20)ng/L] versus group B[(54.70±8.04)ng/L, (37.70±7.10)ng/L]. Malondialdehyde levels increased and total antioxidant capacity levels decreased in group A than B in the lung. Histopathologie examination revealed more inflammatory cells and destructive changes of alveolar wall in group B. Conclusions Large tidal volume DW-3000 ventilation can induce acute lung injury in aged rats after four hours' ventilation.