Experimental study of mature pulmonary lobar allo-transplantation in puppies.

背景：使用小尺寸成人肺移植可以帮助解决严重的儿童供肺短缺问题。然而，成熟移植物要有足够的长期功能，需要与受体发育成比例的生长。方法：取6只成年比格犬（平均体重：12kg）的成熟左下叶，移植至6只年龄：3个月，平均体重：5kg的未成熟比格犬（年龄：3个月，平均体重：5kg）进行左肺切除术。对照组（MD）为5只接受成熟肺大叶移植的成年犬。移植后12个月及以上在机械通气下Fi02 - 1进行右肺动脉闭塞试验。测定心输出量、肺动脉压（PAP），进行股动脉血气分析（PaOa、PaCOa），计算闭塞前后5、10、15、30 min的AaDO2。移植物被移除并进行组织学检查。结果：id5只狗存活，3只狗耐受右肺动脉闭塞试验。在MD中，3只狗存活并耐受闭塞试验。闭塞前、闭塞后30min Pa02、PaCO2、AaDO的变化无显著性差异。组织学研究显示肺实质结构正常，但肺泡增大。结论：在本实验模型中，幼犬成熟肺叶的肺泡结构基本保持正常形态或肺气肿，且成熟肺叶的长期功能保持良好。

Back ground : The use of reduced-size adult lung transplantation could help solve the profound pediatric donor lung shortage. However, adequate long-term function of mature grafts requires growth in proportion to the recipient's development. Methods : Six mature left lower lobes from adult beagles (mean body weight : 12kg) were harvested and transplanted to six immature beagles (age : 3 months, mean body weight : 5kg) that underwent left pneumonectmy (ID). The control group (MD) was 5 adult dogs that underwent mature pulmonary lobar allotransplantation. Right pulmonary arterial occlusion test was performed under mechanical ventilation with Fi02 1 in 12 months or more after transplantation. Cardiac output and pulmonary arterial pressure (PAP) were measured, femoral arterial blood gas analysis (PaOa and PaCOa) was performed, and AaDO2 was calculated before and after occlusion at 5, 10, 15, and 30 minutes. The grafts were removed and examined histologically. Results : In ID, five dogs survived and three dogs tolerated the right pulmonary arterial occlusion test. In MD, three dogs survived and tolerated the occlusion test. There was no significant difference in mean PAP elevation between ID and MD. There were no differences in changes in Pa02, PaCO2 and AaDO before and 30 minutes after occlusion. Histological studies showed normal architecture of lung parenchyma but alveolar enlargement was observed in both ID and MD grafts.Conclusion : We conclude that in this experimental model of mature lobar transplantation in puppies, the alveolar architecture of a mature lobe is almost normal appearance or emphysema, and the long term function of a mature lobe is maintained well.