Zhang R, Wang Z, Wang H, Song H, Zhang N, Fang M
Department of Cardiovascular Surgery, Xijing Hospital, Fourth Military Medical University, Xi'an, China.
J Cardiovasc Surg (Torino). 2010 Jun;51(3):435-42.
Reducing lung injury during cardiopulmonary bypass (CPB) is important for patients' recovery. The present study was designed to evaluate the effects of pulmonary artery perfusion pressure on the extent of lung injury during CPB in an animal model.
Twenty healthy mongrel dogs were randomly divided into four groups, including a control group and three perfusion groups designed to simulate clinical cardiopulmonary bypass-induced lung injury. During pulmonary ischemia and cardiopulmonary bypass, protective perfusions were performed using different perfusion pressures (15-20, 25-30, and 40-45 mmHg), while animals in the control group were not perfused. After pulmonary reperfusion, the changes in pulmonary function and tissue histopathology were determined.
Compared with the control group, lung compliance, oxygenation and vascular resistance after reperfusion were significantly improved in both low- and moderate-pressure groups. The malonaldehyde concentration, neutrophil sequestration ratio, and expression of ICAM-1 were also decreased significantly in the two groups. However, there were no significant differences in any of these parameters between the control group and the high-pressure group. Histopathological examination demonstrated that there were obvious inflammatory cell infiltration and tissue damage in the control and high-pressure groups, which was prevented in the low- and moderate-pressure groups.
The perfusion pressure is an important factor that determines the extent of lung protection, and the use of pressures below 30 mmHg is optimal, with the safest and most effective range being 15-20 mmHg.
减轻体外循环（CPB）期间的肺损伤对患者恢复很重要。本研究旨在评估在动物模型中肺动脉灌注压力对CPB期间肺损伤程度的影响。
将20只健康杂种犬随机分为四组，包括一个对照组和三个灌注组，旨在模拟临床体外循环诱导的肺损伤。在肺缺血和体外循环期间，使用不同的灌注压力（15 - 20、25 - 30和40 - 45 mmHg）进行保护性灌注，而对照组动物不进行灌注。肺再灌注后，测定肺功能和组织病理学的变化。
与对照组相比，低压力组和中压力组再灌注后的肺顺应性、氧合和血管阻力均显著改善。两组的丙二醛浓度、中性粒细胞滞留率和细胞间黏附分子-1（ICAM-1）的表达也显著降低。然而，对照组和高压力组在这些参数中的任何一项上均无显著差异。组织病理学检查表明，对照组和高压力组有明显的炎性细胞浸润和组织损伤，而低压力组和中压力组则未出现。
灌注压力是决定肺保护程度的重要因素，使用低于30 mmHg的压力是最佳的，最安全有效的范围是15 - 20 mmHg。
