Revisiting extended-criteria donors in lung transplantation

Lung transplantation (LTx) is an established life-saving therapy for patients with end-stage lung disease. Despite continuous improvements in surgical technique, immunosuppressive regimen and perioperative care, organ shortage remains the principal limitation to broader access. Historically, conservative donor criteria have contributed to the underutilization of potentially transplantable lungs. Over time, lungs from donors outside standard criteria - commonly referred to as extended-criteria donors (ECD) - have been increasingly accepted. This narrative review evaluates contemporary evidence on the experience and outcomes of specific ECD lungs in LTx. We focus first on typically defined ECD including older donor age, smoking history and substance abuse, oxygenation status, radiological abnormalities, microbial colonization, donation after circulatory death, and extended ischemic times. Subsequently, we look at specific donor traits tempering them as emerging ECD. Finally, we evaluate the role and potential benefits of novel preservation and assessment techniques such as controlled hypothermic storage and ex vivo lung perfusion. While accumulating data support the safe use of ECD lungs under appropriate conditions, a paradigm shift toward individualized donor assessment rather than rigid thresholds is mandatory to sustainably expand the donor pool and reduce waitlist mortality.