Hypothermia during lung preservation decrease metabolic processes. After the rabbit lung was flushed with modified Euro-Collins solution, heart-lung block was harvested and the left lung was assessed after ligation of the right pulmonary artery
and
right main-stem bronchus. Heart-lung block was immersed in the same solution for 6 hours. The modified Euro-Collins solution and storage temperature of group 1(10 cases) was 4℃, group 2(10 cases) was 10℃. On completion of the storage period,
the
left
lung was ventilated and reperfused with blood which used a cross-circulating paracorporeal rabbit as a "biologic deoxygenator" for 60 minutes. Pulmonary artery pressure, airway pressure, difference in oxygen tension between inflow and outflow
perfusate
and degree of pulmonary edema were assessed at 10-minute intervals while the left lung was ventilated at 0.8 of the inspired oxygen fraction.
The mean pulmonary venous oxygen tensions at 10 and 60 minutes after reperfusion were 209.52±42.46 and 103.48±15.96 mmHg in group I versus 247.78±36.19 and 147.91±11.07 mmHg in group II(p=0.049, <0.0001). The mean alveolar-arterial oxygen
differences at 20 and 60 minutes after reperfusion were 357.95±12.84 and 437.31 14.26 mmHg in group I versus 310.88±3.347 and 390.93±15.86 mmHg in group II (p=0.0092, <0.0001). The mean pulmonary arterial pressures at 10 and 60 minutes after
reperfusion were 40.56±18.66 and 87.22±17.22 mmHg in group I versus 31.22±6.84 and 65.78±11.02 mmHg in group II (p=0.048, 0.0062). The mean pulmonary vascular resistances at 10 and 60 minutes after reperfusion were 2.69±0.85 and 4.36±0.86
mmHg/ml/min in group I versus 1.99±0.39 and 3.29±0.55 mmHg/ml/min in group II(p=0.0323, 0.0062). There were no difference between groups in peak airway pressure, lung compliance and degree of pulmonary edema.
In conclusion that preservation of lung at 10℃was superior to preservation at 4℃.
|