中文摘要：

背景：肺保护性通气策略和呼气末正压作为近些年来治疗急性呼吸窘迫综合征（acute respiratory distress syndrome，ARDS）有效通气方式在临床得到广泛的应用，但对其疗效一直有很大的争议。 目的：观察在肺保护性通气条件下ARDS模型犬氧合指数以及外周血和肺不同部位（肺上区、肺下区腹侧和肺下区背侧）支气管肺泡灌洗液中炎性递质的变化。 设计：随机对照动物实验。 单位：解放军总医院呼吸科。 材料：取健康成年雄性杂种犬24只。单纯随机分为肺内源性ARDS实验组、肺内源性ARDS对照组、肺外源性ARDS实验组和肺外源性ARDS对照组。每组6只。 方法：采用静脉注射油酸0．1～0．15mg／kg形成肺外源性ARDS动物模型；应用十六烷磺基丁二酸钠盐气管内吸入形成肺内源性ARDS动物模型。实验组肺损伤后进行肺保护性通气（潮气量：8mL/kg。呼气末正压：0.981kPa）3h。对照组继续进行大潮气通气（潮气量：14-17mL／kg。呼气末正压：0kPa）3h。 主要观察指标：①各组犬氧合指数的变化。②动态观察肺保护性通气条件下各组犬外周血和肺不同部位（肺尖叶、肺心叶和肺膈叶）支气管肺泡灌洗液中炎性递质（肿瘤坏死因子α，白细胞介素1β和白细胞介素6）的变化。 结果：24只犬全部进入结果分析。①肺损伤后各组犬氧合指数均显著下降。应用肺保护性通气治疗后实验组氧合指数明显高于对照组（P〈0．05）；肺保护性通气后2h和3h肺外源性ARDS实验组氧合指数咀显高于肺内源性ARDS实验组（P〈0．05）。②肺损伤后各组外周血中炎性递质明显升高。应用肺保护性通气治疗后。炎性递质水平有不同度下降。但肺内源性ARDS实验组的治疗效果不如肺外源性ARDS实验组。③肺内源性ARDS模型犬肺尖叶和肺心叶支气管肺泡灌洗液中炎性递质水平明显高于肺外源性ARDS模?

英文摘要：

BACKGROUND： Lung protective ventilation strategies and positive endexpiratory pressure （PEEP） have been widely used as an effective ventilation pattern in clinical practice of administration of acute respiratory distress syndrome （ARDS） in recent years, but there are still great arguments on the therapeutic effects. OBJECTIVE： To observe the changes of oxygenation index and inflammatory transmitters in peripheral blood and bronehoalveolar lavage fluid （BALF） of different lung areas [superior area of lung （upper lobe）, ventral side of inferior lung （heart lobe）, and dorsaliS inferior lung （diaphragm lobe）] of ARDS dogs caused by pulmonary and extrapulmonary insults under lung protective ventilation treatment. DESIGN： A randomized control animal study. SETTING： Department of Respiratory Medicine, the General Hospital of Chinese PLA. MATERIALS： Twenty-four adult healthy male mongrel dogs were randomly divided into four groups with 6 dogs in each： pulmonary ARDS experimental group, pulmonary ARDS control group, extrapulmonary ARDS experimental group and extrapulmonary ARDS control group. METHODS： Models of extrapulmonary ARDS were induced by intravenous injection of oleie acid （0.1-0.15 mg/kg）, and the pulmonary ARDS models were established by intratracheal administration of diocty sulfosuccinate sodium salt. After lung injury, the experimental groups received lung protective ventilation treatment （tidal volume： 8 mL/kg, PEEP： 0.981 kPa） for 3 hours, and the control groups also received ventilation of large tidal volume （tidal volume： 14-17 mL/g, PEEP： 0 kPa）. MAIN OUTCOME MEASURES： （1） changes of oxygenation index in each group; （2） dynamically observed the changes of the inflammatory transmitters [tumor necrosis factor alpha （TNF-α）, interleukin-1 beta （IL- 115） and interleukin-6 （IL-6）] in peripheral blood and BALF of different lung areas （upper lobe, heart lobe and diaphragm lobe） of ARDS dogs under lung protective ve