For extended criteria donor organs or DCDD organs, what unique benefit does machine perfusion offer beyond simple preservation?

Extended criteria donor (ECD) organs are those from donors with characteristics that typically pose a higher risk of poorer outcomes post-transplantation, such as advanced age or comorbidities. Donation after circulatory death (DCDD) organs are retrieved after the donor's heart has stopped beating, resulting in a period of warm ischemia, where the organ is deprived of blood flow at body temperature before preservation begins. Simple preservation, known as static cold storage, involves immersing the organ in a cold solution, slowing its metabolism to minimize damage. However, for ECD and DCDD organs, which often arrive with pre-existing damage or have experienced warm ischemia, static cold storage offers no opportunity to assess their actual functional health or to actively improve their condition. Machine perfusion, in contrast, circulates a specialized preservation solution through the organ's vasculature at controlled temperatures, eit....