A simplified preservation method for lungs donated after cardiac death

Abstract

The shortage of donor lungs restricts the number of lung transplantations that can be performed. However, extension of the donor pool using organs donated after cardiac death (DCD) could potentially increase the number of patients who undergo transplantation. To establish acceptance among hospital personnel and the donor's next of kin for the uncontrolled DCD procedure we proposed a simplified preservation regime for intrapleural cooling of the donor lungs. In an uncontrolled DCD model, 12 pigs were randomized to intrapleural lung cooling using either a standard method with two bilateral chest tubes and intermittent pleural fluid exchanges, or a simplified, less-invasive method with a single bilateral chest tube and filling of the pleural space without fluid exchange. Lungs were explanted and graft function was assessed during ex vivo lung perfusion (EVLP) and by histologic examination. Although the mean temperature after 120 minutes of intrapleural cooling was significantly higher in the lungs cooled using the simplified method (25.9°C vs 13.5°C), this did not affect the oxygenation capacity, pulmonary vascular resistance or dynamic compliance of the lungs, as recorded during EVLP. Furthermore, no differences were found between the lungs preserved by the two methods with respect to the wet/dry ratio, levels of myeloperoxidase in bronchoalveolar lavage, or at histologic examination. The simplified technique for DCD lung cooling results in a higher preservation temperature but does not affect lung function during EVLP, which implies that this less invasive method can be used in the uncontrolled DCD setting. This is another step forward in the development of a simplified preservation routine for DCD.