State of the Art of Living Donor Lung Transplantation

Living donor (LD) lung transplantation (LT) is a potential alternative to cadaveric LT offering favorable results to both donors and recipients. This opportunity is most commonly offered to those patients having a limited survival expectancy on the cadaveric waiting list. LDLT was popularized in Japan over the last 20 years, while being less common in European and North American countries where cadaveric donation is more available. Donor-to-recipient size matching is crucial for LDLT in order to provide the best fitting lobar or sub-lobar grafts. Functional size matching, based on forced vital capacity (FVC), and anatomical size matching, based on 3-dimensional computed tomography volumetry, are employed to ensure that the graft falls within the limits to allow a progressive adaptation to the recipient. Standard LD LT is a sequential, bilateral, lower lobe LT. In case of an undersized match, the two native upper lobes can be spared to decrease the potential residual dead space or a right-to-left inverted LD lobar LT can be performed. On the other hand, when the graft is oversized, coping strategies include delayed chest closure, single-lobe living transplant (LT), and bilateral middle lobe or segmental LT. The results of LDLT, in terms of of recipient survival and peri-operative mortality, are comparable to those of patients receiving a cadaveric lung transplant. LDLT is also a well-tolerated procedure for donors, considering the importance of preserving donor safety and well-being, both from a functional and psychological standpoint. In the near future LDLT may benefit from the adoption of minimally invasive or robotic surgery techniques to decrease the invasiveness of the procedure in lung donors. Also, in the future, a larger number of patients on the waiting lists could benefit from LDLT, such as those who could develop immunological tolerance from receiving a graft from an appropriately selected donor. In summary, LDLT is becoming a widely accepted strategy to safely expand the donor pool providing patients on the waiting list with another chance to receive a viable organ.