Background: The blocking of pulmonary vessels, including the blocking of pulmonary artery and pulmonary circulation, is always applied in the surgical treatment of locally advanced no-small cell lung cancer. However, the blocking of pulmonary vessels will induce lung ischemia-reperfusion injury (LIRI). The aim of this study is to establish pulmonary vessels blocking model in rabbit and to investigate the LIRI in pulmonary surgery.
Methods: 114 New Zealand rabbits were randomly divided into 3 groups: group I, control group; group II, block left pulmonary artery; group III, block left pulmonary artery and vein. After the time of opening chest (group I), 1 h ischemia and 1 h, 2 h, 4 h, 6 h, 24 h reperfusion, the changes of arterial oxygen partial pressure in left pulmonary vein (PaO2) and the content of MDA in left lung tissue were observed. Then the water content of left lung and pathological study was recorded.
Results: Homodynamic parameters were stable in all 3 groups. There were significant differences in PaO2, MDA and wet/dry ratio of the lung tissue between I and other two groups at the time of 1 h ischemia and 1 h, 2 h, 4 h, 6 h reperfusion (P <0.05 and P < 0.01), but there was no significant difference between group II and group III (P >0.05), and there was no significant difference among the three groups after 24 h reperfusion (P >0.05). Pathological study revealed that similar injury changes happened between group II and group III, and the obvious injury happened at the time of 4 h reperfusion. At the time of 6 h reperfusion pathological changes in both group II and group III began to recover, and completely recover after 24 h reperfusion.
Conclusions: The lung ischemic-reperfusion injury caused by blocking pulmonary artery is similar to that caused by blocking pulmonary artery and veins. It is safe to previously block pulmonary vessels within 1 h during pulmonary surgery.