Compared to the other organ transplantations, lung and heart-lung transplantations have the following peculiarities: (1) bacterial colonization of the bronchi or lung parenchyma is almost constant because of the contact of donor's and recipient's lungs to the air through the intubation tube; (2) the lung is a particularly fragile organ and sensitive to the hemodynamic modifications in the donor following brain death; (3) the lung is the only organ transplanted without systemic revascularization, which increases the risks of bronchial ischemia, bronchomalacia, and mucociliary dysfunction; and (4) the lung has a large amount of lymphoid tissue, rendering it particularly immunogenic.