Dynamic liver preservation: current evidence and future challenges

Background and Study Aims: Liver transplantation (LT) is limited by organ shortage. Dynamic preservation (DP) techniques have rapidly become the standard of care in liver graft preservation, particularly for extended criteria donors (ECD). This study reviews the clinical applications and future potential of various DP techniques in LT.

Patients and Methods: A literature review was conducted using Medline (PubMed) to identify relevant studies on DP techniques, including normothermic machine perfusion (NMP), hypothermic oxygenated perfusion (HOPE), and normothermic regional perfusion (NRP).

Results: A growing number of high-impact studies support the clinical implementation of MP techniques. NMP maintains the organ metabolically active, enabling real-time graft viability assessment through markers of function and injury. When initiated at the donor hospital, NMP helps reduce or even eliminate ischemia-reperfusion injury (IRI). HOPE, on the other hand, mitigates IRI by supporting mitochondrial recovery, with flavin mononucleotide serving as a reliable surrogate marker of graft function. Importantly, both NMP and HOPE allow for safely extended preservation times, improving LT logistics and avoiding the need for nighttime procedures. NRP restores oxygenated blood flow in donation after circulatory death donors, reducing biliary complications and improving graft outcomes compared to rapid organ recovery. Emerging strategies, such as controlled oxygenated rewarming, combine HOPE and NMP to sequentially optimize graft preservation and assessment.

Conclusions: DP has revolutionized liver preservation, providing superior outcomes compared to static cold storage, particularly for ECD. Clarity and consensus are needed regarding the definition of clinically relevant endpoints to broaden the applicability of study results on DP.

Keywords: liver transplantation, organ preservation, machine perfusion, normothermic perfusion, hypothermic oxygenation, extended criteria donors.