以P-V曲线为导向的肺复张策略对肺内/外源性急性呼吸窘迫综合征模型肺损伤的影响

目的探讨以压力-容积（P-V）曲线为导向的肺复张（RM）策略对肺内/外源性急性呼吸窘迫综合征（ARDS）模型犬肺损伤的影响。方法健康犬24只,随机分为肺外源性ARDS（ARDSexp）组和肺内源性ARDS（ARDSp）组,每组12只,静脉注射油酸复制ARDSexp模型,盐酸灌肺复制ARDSp模型,再随机各分为两组,每组6只,分别采用肺保护通气策略（LPVS）和LPVS联合以P-V曲线为导向的RM（LPVS＋RM）进行机械通气。RM采用压力控制通气（PCV）,压力上限为高位转折点（UIP）,呼气末正压（PEEP）为低位转折点（LIP）＋2 cm H2O,维持时间60 s。观察两组肺泡灌洗液（BALF）中炎症介质水平;实验结束取肺组织行病理评分,比较各组肺损伤评分。结果与LVPS组相比,LPVS＋RM组肺损伤评分明显减少,BALF中炎症介质上升幅度明显降低,且ARDSexp组改善程度均明显优于ARDSp组（P〈0.05）。结论对于不同原因ARDS,以P-V曲线为导向的RM均具有减轻肺损伤的作用,且对ARDSexp的治疗效果明显优于ARDSp。

Effect of recruitment maneuver strategy guided by pressure-volume curve on lung injury in a canine model of ARDSexp and ARDSp

Objective To determine the effect of recruitment maneuver（RM） guided by pressure-volume（P-V） curve on lung injury in canine models of acute respiratory distress syndrome（ARDS） with pulmonary and extrapulmonary origin（ARDSexp and ARDSp）. Methods Twenty-four healthy dogs were randomly divided into ARDSexp group and ARDSp group.Each group contained 12 dogs.ARDSexp dogs were injected with oleic acid through femoral vein and ARDSp dogs were inspired hydrochloric acid to cause lung injury.ARDSexp and ARDSp dogs were randomly divided into lung protective ventilation strategy（LPVS） group,lung protective ventilation strategy and recruitment maneuver（LPVS＋RM） group.Pressure controll ventilation（PCV） was employed to RM,and Phighwas set as UIP,Plowwas set as LIP＋2 cm H2 O,the duration of RM was set as 60 s.Inflammatory mediators in bronchial alveolar lavage fluid were measured before and after ARDS model establishment.Pathological scores was performed 4 hours after RM. Results Compared with LPVS group,the lung injury score in LPVS ＋RM group was significantly decreased,and the rises of inflammatory mediators in BALF was obviously decreased,but ARDSexp group rallied better than that in ARDSp group（P〈0.05）.Conclusion RM guided by P-V curve can relieve inflammatory response in ARDSexp and ARDSp,and has better effect in ARDSexp dogs than ARDSp dogs.