Liver Graft Preservation

During hypothermic static storage, reduced temperature slows the graft’s metabolism, lowering its activity while the liver remains outside the recipient. The preservation solution provides the storage environment used during this interval. By limiting metabolic demand, this approach helps reduce ischemic injury before blood flow is restored, which is important for protecting later graft performance after transplantation.

Machine perfusion circulates preservation fluid through the liver graft rather than leaving it static. The fluid may be oxygenated or nonoxygenated, allowing different preservation conditions to be applied. This circulation supports cellular energy balance, and the system can also provide an opportunity to assess organ function before transplantation, particularly when graft suitability is uncertain.

Preservation-related damage can become evident after blood flow is restored to the graft during transplantation. Strategies that limit ischemic injury during the preservation interval are therefore intended to reduce harm associated with this transition. Protecting the liver through storage or perfusion can support better graft performance and contribute to improved outcomes after transplantation.

Both approaches circulate fluid through the graft, but oxygenated perfusion additionally supplies oxygen during the preservation period. This distinction is relevant because machine perfusion can support cellular energy balance while the liver is outside the body. Nonoxygenated circulation remains another preservation option, whereas oxygenated systems combine fluid movement with oxygen delivery and can support functional assessment.

The preservation interval begins after donor liver procurement and continues until transplantation. During this period, the graft can be placed in hypothermic static storage with a preservation solution or connected to a machine that circulates oxygenated or nonoxygenated fluid. The selected approach is intended to maintain viability, limit ischemic injury, and provide information about function when machine perfusion is used.

These methods are particularly relevant when clinicians consider grafts from donation after circulatory death or other higher-risk donors. By reducing preservation-related injury and, with machine perfusion, enabling functional assessment, they may support safer use of organs that present greater preservation challenges. More effective preservation can also broaden the pool of donor livers available for transplantation.