Bilateral native lung-sparing lobar transplantation in a canine model

Objective: Bilateral living-donor lobar lung transplantation has become an accepted approach in response to the cadaveric lung donor shortage. Because only one lobe is implanted in each chest cavity, this procedure is usually confined to patients of small size. The purpose of this study was to develop a technique of bilateral native lung-sparing lobar transplantation that can be applied to large adult patients. Methods: Bilateral native lung-sparing lobar transplantation was performed in 12 pairs of dogs. In donor animals the right middle, lower, and cardiac lobes were separated as a right graft, and the left lower lobe was separated as a left graft. In recipient animals these 2 grafts were implanted in the natural anatomic position with sparing native right upper, left upper, and middle lobes. In an acute study (n = 6), transplanted graft function was assessed for 3 hours after ligation of the pulmonary artery branches to the native spared lobes. In a chronic study (n = 6) the immunosuppressed recipients were observed for 3 weeks to assess the quality of bronchial healing and long-term pulmonary function. Results: Morphologic adaptation of the 2 grafts was found to be excellent. All 6 animals in the acute study showed excellent pulmonary function. Five of 6 animals in the chronic study survived for 3 weeks, with excellent pulmonary function and satisfactory bronchial healing. Conclusion: Bilateral native lung-sparing lobar transplantation was technically possible and associated with excellent pulmonary function and good bronchial healing in a canine experimental model.