摘要目的 探讨外源性肺表面活性物质(PS)稀释剂延迟肺灌洗对大鼠严重烟雾吸入伤后内源性PS功能障碍和急性呼吸衰竭的治疗效果.方法 90只Wistar大鼠随机分为5组:Ⅰ组,正常对照(n=14);Ⅱ组,烟雾吸入(n=27);Ⅲ组,烟雾+PS灌洗+机械通气(MV),n=21;Ⅳ组,烟雾+盐水灌洗+MV,n=10;V组,烟雾+MV,n=18.伤后2 h经气管插管注入含PS(100ms/ks)的等渗盐水30 ml/kg或等量盐水行肺灌洗,MV 4 h,观察24 h;检测动脉血气、肺水量、静态肺顺应性(Cst)、支气管肺泡灌洗液(BAIF)蛋白含量、BALF表面张力特性和24 h病死率等.结果 致伤动物伤后立即出现严重缺氧和一氧化碳中毒;Ⅱ组发生急性呼吸衰竭、高通透性肺水肿和PS功能障碍;Ⅲ组Cst和BALF表面张力特性显著改善(P<0.05),但氧合能力、肺水量和BALF蛋白含量无明显好转(P>0.05).Ⅳ、V组疗效不佳.结论 外源性PS稀释剂延迟肺灌洗可一定程度恢复烟雾吸入所致内源性PS功能抑制,改善肺功能,但不能显著减轻高通透性肺水肿和呼吸衰竭,不能降低早期病死率.

abstractsObjective To investigate the therapeutic effects of delayed lung lavage with exogenous pulmonary surfactant(PS)diluent on endogenous surfactant system dysfunction and acute respiratory failure caused by severe smoke inhalation in rats.Method Ninety Wistar rats were randomly separated into five groups:Group I,normal control(n=14);Group Ⅲ,smoke inhalation(n=27);GroupⅢ,smoke+PS lavage+mechanical ventilation(MV),n=21;Group IV,smoke+saline lavage+MV,n=10;Group V,smoke+MV,n=18.The lungs were lavaged with 30 ml/kg normal ssdine containing 100 mg/kg PS or same volume of saline via tra cheal catheter at 2 h after smoke inhalation,then the animals were placed on a ventilator for 4 h,and observed until 24 h after injury.The arterial blood gas level,lung water volume,static lung compliance(Cst),total protein and albumin contents in bronchoalveolar lavage fluid(BALF),surface tension properties of BALF,and fatality rate at 24 h were measured.Results Smoke inhalation caused a similar acute hypoxia and severe carbon monoxide poisoning immediately in all injured groups.The animals in group Ⅱ showed acute respiratory failure,serious hish permeability pulrnonary edema,and surfactant system dysfunction.The surface tension properties of BALF and Cst were significantly improved by delayed lung lavage treated with exogenous PS diluent in group m(P<0.05).However,the lung water volume,total protein and albumin contents in BALF and the oxygenation had not significant difference between group Ⅲ and group Ⅱ(P>0.05).Conclusions Delayed lung lavage with exogenous PS diluent,at a certain extemt,restored endogenous suffactant function inhibited by smoke inhalation and improved lung function.Nevertheless,the trent could not alleviate rash permeability pulmonary edema and respiratory failure drarnatically.The expected decrease of mortality at early stage after smoke inhalation injury was not showed yet.