Abstract
We have performed left lung transplantation followed by ligation of right pulmonary artery in 14 dogs at the Chest Disease Research Institute, Yonsei University College of Medicine from May 1992 to February 1994. Excised left lung was perfused with 1500cc of 4$^{\circ}$C cold Euro-Collin`s[E-C] solution at a pressure of 30cmH2O through main pulmonary artery and preserved in 4$^{\circ}$C cold E-C solution for one hour. Left lung transplantation were proceeded in order of left atrium, left main bronchus, left pulmonary artery and right pulmonary artery ligation as usual method. The femoral artery and pulmonary artery pressures were monitored for more than 5 hours after the transplantations in 14 dogs. Six recipient dogs had elevated mean pulmonary artery pressure to greater than 30mmHg after the left lung transplantation and ligation of right pulmonary artery. The cause of elevated mean pulmonary artery pressure was due to inadequate preservation resulting in ischemic damage to donor lungs in 3 cases, and inadequate surgical techniques in 3 cases. Two recipient dogs without surgical complications died immediate post-operatively due to hemorrhagic shock. The bleeding focuses were LA anastomotic site in one case and femoral artery puncture site in another case. The remaining 6 recipient dogs showed mean pulmonary arterial pressure less than 30mmHg. However, one dog had spontaneous pneumothorax in post-operative 4 days, and another dog had rejection phenomenon in post-operative 5 days which was confirmed by pathologic findings of extracted transplanted lung. One dog succumbed of severe hemoptysis which was due to lung abscess with pin point stenosis of bronchial anastomosis in post-operative 38 days. In conclusion, elevated mean pulmonary arterial pressure greater than 30mmHg in immediate postoperative period can be due to inadequate preservation of extracted lung or poor surgical techniques. And the two dogs succumbed of hemorrhagic shock even though the mean pulmonary arterial pressure was less than 30mmHg. It is thought that careful preservation of the extracted donor lung in 4oC E-C solution and complete surgical techniques are the most important factors early and late complications.