Experimental Study Of Pulmonary Artery Perfusion Of Lung Protection Solution

Objective To establish a rabbit in situ left lung preservation model undergoing ischemia, pulmonary infusion with lung preservation solution, cold storage and reperfusion which can be used to compare, identify lung preservation solution and can minimize the disturbance of non-experimental factors for the study of effectiveness of lung slush solution. Methods Fifty New Zealand white rabbits were selected as experimental subjects, weight ranging from 2500~3500g. Ten New Zealand white rabbits were used at the pre-experimental stage, in order to establish and optimize the rabbit in situ left lung ischemia, pulmonary infusion, cold storage and reperfusion model (rabbit in situ lung preservation model). Forty New Zealand white rabbits were used at the formal experimental stage. By left thoracotomy, left superior pulmonary artery was separated and was inserted into a catheter and then left upper lobe was removed. Another catheter was inserted into the left inferior pulmonary vein via left atrial wall. Both catheters were connected to sensors to detected pressure. After left lung root was clamped, lung flush solution was perfused through the catheter in the left superior pulmonary artery and was drained via the catheter in the left inferior pulmonary vein. The left lower lung lobe was put and stored in a specially made lung container at 10 centigrade for 2 hours. Thereafter, the lung root was unclamped for 2 hours. After samples were collected, the subjects were executed by euthanasia. Results In the pre-experimental stage, 5 rabbits out of 10 failed to finish the model making due to hemorrhage, with the successful rate of 50%. With the innovated technique, in the formal experimental stage, all the 40rabbit models were accomplished successfully. The physiological parameters, such as blood pressure, heart rate and body temperature at pre-thoractomy (89.8 ± 11.9mmHg,> 213.4 + 34.7bpm^ 39.06 + 0.12 °C ), pre-clamping of the lung hilus(88.6 + 5.5 mmHg, 216.0 + 27.7bpm,39.06 + 0.23"C)>30 minutes after clamping ofthe lung hilus( 91.6 + 8.3 mmHg > 211.5 + 27.5bpm , 39.04 + 0.28 °C ) , pre-unclamping the lung hilus (90.5 + 8.8 mmHgx 2 12.1 + 25.3bpm> 39.05±0.32°C K post-unclamping the lung hilus ( 90.8 + 8.2 mmHg, 211.6 + 30.9bpn^ 39.04 + 0.32°C ), before end of experiment ( 91.0 + 5.9mmHg, 210.1 ± 27.8bpm > 38.97 +0.13 °C ) were all stable and there was no significant difference among different time points. All the specimen were obtained successfully. Conclusion Rabbit in situ lung preservation model, as an ideal model to study the effectiveness of lung slush solution, is simple, physiological, stable, safe and practical, which can avoid the disturbance of many non-experimental factors. It can also be fed after end of experiment to make chronic animal model to investigate the long term effect on lung tissue after lung ischemia, cold storage and reperfusion.