体外循环中有效的肺动脉灌注方式

摘要

Objective Lung injury occurred during cardiopulmonary bypass as a result of both ischemic-reperfusion injury and systemic inflammatory response is critical for patients' recovery. This study was designed to establish a convenient and appropriate mode for pulmonary artery perfusion and evaluate its effects on the cardiopulmonary bypass-induced lung injury.Methods Fourteen healthy mongrel dogs were randomly assigned to a control group and a perfusion group, which were designed to simulate clinical cardiopulmonary bypass-induced lung injury. Pulmonary arteries were perfused with modified low-potassium dextran solution immediately after the initiation of pulmonary ischemia and before reperfusion, with a pressure of 15 to 20 mm Hg for the perfusion group. Pulmonary arteries of animals in the control group were not perfused. After pulmonary reperfusion, changes in the pulmonary function were evaluated. Results After pulmonary reperfusion, deterioration in the pulmonary function with various severity was identified in both groups. Pulmonary injury in the control group decreased significantly as manifested by a substantial elevation in PVR [with a change of ( 76 ± 7 ) %], decreased compliance [with a change of (30 ±4) %] and decreased oxygenation index [with a change of (45 ±5 ) %]. In contrast, the injury in perfusion group, as compared with that in the control group, was relatively moderate, with a lower PVR [with a change of ( 28 ± 3 ) %, P ＜0.01 )] ,a higher compliance [with a change of ( 12 ± 2 ) %, P ＜ 0. 01] and a better oxygenation index [with a change of (19 ± 2 )%, P ＜ 0.01]. Conclusion The pulmonary perfusion mode used in this experiment could relieve the cardiopulmonary bypass-induced lung injury and preserve pulmonary function effectively. It was expected that this perfusion mode could be used in the cardiosurgery practice expediently, without interfering with the scheduled operation proceeding obviously.%目的 探索方便、有效的肺动脉灌注模式,以缓解体外循环心脏术后肺损伤.方法 14只健康家犬模拟临床体外循环肺损伤特点建立动物模型,随机平均分为对照组及灌注组.体外循环期间,分别于实验肺缺血之初及再灌注之前,以15～20 mm Hg(1 mm Hg=0.133 kPa)的灌注压力短时间对灌注组动物实验肺实施改良低钾右旋糖酐保护液灌注;对照组动物无保护液灌注.90 min体外循环肺缺血后,再灌注4 h,行实验肺肺功能变化测定.结果 再灌注后,两组动物实验肺肺功能均有不同程度的恶化.对照组,再灌注后实验肺顺应性及氧合指数均有较大幅度的下降,分别为(30±4)%及(45±5)%,肺血管阻力指数明显上升,幅度为(76±7)%;与对照组比较,灌注组上述指标的变化幅度均明显降低,分别为[(12±2)%,t0.01/2,12=4.885,P＜0.01];[(19±2)%,t0.01/2,12=5.656,P＜0.01];[(28±3)%,t0.01/2,12=6.853,P＜0.01)].结论 应用肺动脉灌注方式可明显减轻体外循环过程中肺组织的损伤,保护肺功能;实验的灌注方式可望方便地应用于临床体外循环心脏手术过程,不会明显干扰既定手术进程.