幼猪体外循环期间应用氟碳化合物乳剂对肺气体交换的影响

摘要

[Objective] To observe the effect of partial liquid ventilation (PLV) during cardiopulmonary bypass on gas exchange and histopathological changes of lung. [Methods] After cardiopulmonary bypass (CPB) was established, eighteen piglets were assigned randomly into 3 groups. Group I (Control Group): Animals in control group received no treatment but conventional mechanical ventilation; Group U ; 5 mL/kg Oxygent· Was instilled into the trachea during CPB; Group Ⅲ : 15 mL/kg Oxygent·was instilled into the trachea during CPB. The changes of gas exchange and lung compliance were examined before CPB, 5 min, 0.5 h, 1, 1.5, and 2 h after withdraw of CPB. Histological sections were taken from right downsides of lung and stained by H&E. [ Results ] The P,,o, significantly increased and alveolar-arterial oxygen gradient (AaDOj) markedly decreased in low dose PLV group (group Ⅱ ) compare with control group (group I ) and large dose group (group Ⅲ ) (P<0.05) at the time of 0.5, 1, 1.5, and 2 h post-CPB. The histopathological lesions of lung were less severe in low dose PLV group (group Ⅱ) compare with control group and large dose group (group Ⅲ ). [Conclusion] Partial liquid ventilation during CPB with low dose Oxygent· Can improve the oxygenation of lung and increase the Pa,O2 after CPB.%[目的]探讨在幼猪体外循环期间应用以氟碳化合物乳剂为媒介的部分液体通气模式对体外循环后幼猪肺组织气体交换的影响以及病理改变.[方法]18只幼猪随机分为3组,Ⅰ组为对照组,即单纯体外循环(CPB)组；Ⅱ组于体外循环期间在肺内灌入5 mL/kg的氟碳化合物OxygentTM;Ⅲ组于体外循环期间在肺内灌入15 mL/kg OxygentTM.分别在CPB前、停CPB 5 min及停CPB后0.5、1、1.5、2h观察动脉血气指标以及肺动态顺应性的变化,并计算氧合指数.实验结束后取右肺下叶基底段做病理切片.[结果]与对照组比较,Ⅱ组停CPB后0.5、1、1.5、2h时点动脉血氧分压(Pa,O2)明显升高,氧合指数明显增加,肺顺应性明显改善(P＜0.05).Ⅲ组与对照组无明显差异.病理切片比较,小剂量组(Ⅱ组)病变轻于对照组和Ⅲ组.[结论]在幼猪CPB期间应用小剂量(5 mL/kg) OxygentTM进行部分液体通气,可明显地改善体外循环后其肺氧合能力,改善肺顺应性,减轻肺部的病理改变.