Lung Injury Induced By Aortic Cross-clamping And Protection Of Propofol

The protective effects of propofol on lung impaired by descending aorta cross-clamping in canine modelObjectives To study the protective effect of propofol on canine lungs injuried by descending aorta cross-clamping.Methods Eighteen dogs were randomized into three groups: control group n=6), clamping group n=6) and propofol group n=6). All the animals were ventilated mechanically. 5 F Swan-Ganz catheter was put in through outer jugular vein. 8F Fogarty catheter was put into descending aorta through femoral artery to make subdiaphragmatic ischemia. The aorta was reopened after 60 min occlusion. Hemodynanic and respiratory parameters were recorded at four time points: beforeaorta occlusion, at the end of aorta occlusion, 1 hr and 4 hr after reperfusion. Macrophages in alveolar were harvested by bronchoalveolar lavage. The contents of SOD, MDA and LDH in plasma and BALF were assessed at each time point. The expression of IL-8 and TNF-α mRNA in Macrophages were assessed by RT-PCR at each time point.Result 1. There was no difference in general data among the three groups.2. MAP and CO in clamping and propofol group showed similar changes. PVR increased 4 hours after reperfusion both in clamping and propofol group and the increase extent in clamping group was more than that in propofol group. 3. The peak airway pressure increased in all the three groups after reperfusion and the clamping group showed the greatest increase. Pulmonary compliance decreased after reperfusion in all the three groups and the clamping group showed the greatest decrease.The cell counts in BALF showed no significant difference in all the three groups. However the neutrophil in BALF increased the most in clamping group.4. The activity of SOD in plasma and BALF began increasing 1hr after cross-clamp in propofol group P 0.05), and it was higher in propofol group than that in other two groups P 0.05). After reperfusion, the content of MDA in plasma increased significantly in cross-clamp group P 0.05), but it decreased in propofol group. The activity of LDH in plasma was higher in propofol and cross-clamp groups than that in control group P 0.05). 5. Total protein concentration in BALF increased significantly in cross-clamping and control group P 0.05) 1hr and 4hr after reperfusion, it was higher in the cross-clamping group than that in control group, however it did not change in propofol group. The W/D ratio in left low lobe of the lung showed no difference among three groups. 6. Among the three groups, the expression of IL-8 mRNA 4hr after reperfusion was higher than that before cross-clamp, and it was higher in clamping group than that in the other two groups. The expression of TNF- mRNA in propofol and cross-clamp group was higher than control group, and it was higher in cross-clamp group than that in propofol group.7. Pathologic examination shows that the alveolar athletic and PMN adhering to endothelium in clamping group. Conclusions cross-clamping of the thoracic aorta can cause acute lung injury in canine model. Propofol can protect the lung from this injury by inhibition of lipid peroxidation and inflammatory reaction. Part ⅡProtective effects in patients undergoing abdominal aortic aneurysm repairObjective To study the protective effects in patients undergoing abdominal aortic aneurysm repair.Material and Methods 20 patients who suffered infrarenal abdominal aortic aneurysm AAA) were assigned as control group n=10) or Propofol group n=10). All patients received epidural block combined with general anesthesia. Hemodynamic parameters, respiratory parameters and blood gas results were recorded before and 5min after cross-clamping, 5min and 1hr after reperfusion, at the end of operation. Alveolar macrophages were harvested by bronchoalveolar lavage immediately after induction and at the end of operation. Expressions of inerlukin-1β IL-1β) and TNF-αmRNA in the macrophages were measured by semiquantitative polymerase chain reaction using β-actin as an...