Lung biomolecular profile and function comparing graft from marginal brain-dead donors and donors after cardiac death

Donation after cardio-circulatory death (DCD) might address the limited availability of grafts for lung transplantation (LuTx). We explored graft function, metabolism, inflammasome, endothelial function, and glycocalyx shedding during Ex-Vivo Lung Perfusion (EVLP) in lungs grafts from DCD compared to marginal brain-dead donors (DBD) and correlate it to post-LuTx outcomes. Methods: From January 2018 to February 2020 all grafts treated with EVLP and subsequently transplanted were studied. Donors’ data, harvesting procedure timings, recipient outcomes and graft function up to 1 year post LuTx were collected. Perfusate samples were obtained hourly during the EVLP to quantify graft function, metabolism, inflammatory molecules, glycocalyx breakdown products, coagulation and endothelial activation markers. Results: 8 DBD and 7 DCD grafts were enrolled. DCD’s warm ischemia time in-situ was 201 [185; 247] min. Duration of mechanical ventilation was longer in the DBD group. Recipient’s populations did not differ for neither preoperative status nor intraoperative management. No difference was found in lung function during EVLP. Recipients’ outcomes are shown in Table. During EVLP at reperfusion a wash-out phenomenon of both inflammatory cells and microthrombi is observed more in the DCD grafts. In all grafts the perfusate molecular profile showed marked endothelial activation, resulting in the release of inflammatory mediators and glycocalyx breakdown products. Conclusions: Lungs from marginal DBD and DCD are qualitatively comparable. Even in cases of prolonged warm ischemia, DCD lungs, if properly preserved and evaluated, represent a viable resource for donation.