Beyond preservation: future machine perfusion for liver assessment and repair.

Machine perfusion is an emerging and transformative technology for dynamic organ preservation, assessment and repair. Whereas allografts continuously degrade during static cold storage, short-term perfusion can preserve high-quality organs for hours, enabling assessment, regional transport and improved logistics. Long-term perfusion for multiple days might extend the potential of clinical machine perfusion in the future, allowing for the assessment, reconditioning and repair of marginal or injured grafts for which more time is needed. In addition, it might convert transplantation, which is now semi-elective thanks to short-term perfusion, to a fully elective procedure via customized machines and associated protocols that maintain organs ex situ for up to 2 weeks. The advent of long-term organ perfusion provides tremendous potential to improve organ evaluation and selection, to recondition or repair marginal grafts and, ultimately, to expand the pool of grafts available for transplantation. In this Perspective, we discuss design considerations, guidelines for use, and future perspectives of machine perfusion in the context of organ assessment and repair, with a focus on the liver.