organpreserving

Organ preservation is the set of techniques used to maintain the viability and function of organs outside the body for transplantation or for organ-preserving surgical procedures. The aim is to minimize ischemic injury, maintain cellular integrity, and enable safe procurement, transport and implantation. Preservation practices also influence outcomes after transplant and may broaden the pool of usable organs.

Methods range from static cold storage to dynamic machine perfusion. Static cold storage flushes the organ with a cold preservation solution and stores it at near-freezing temperatures to slow metabolism. Machine perfusion circulates oxygenated perfusate through the organ; hypothermic machine perfusion operates at low temperatures to reduce metabolic demand while enabling assessment, and normothermic machine perfusion maintains near-physiologic temperature with nutrients and oxygen to support ongoing metabolism and functional testing. Common preservation solutions include University of Wisconsin (UW) solution and histidine-tryptophan-ketoglutarate (HTK). Important metrics include cold ischemia time and, for some organs, warm ischemia time, both of which influence graft survival and function.

Applications include kidney, liver, heart, lung, pancreas, and intestine transplantation, with organ-specific considerations. In donation after circulatory death, perfusion strategies help mitigate ischemic injury and expand donor use. Beyond transplantation, organ-preserving approaches are also part of organ-sparing strategies in surgery, such as nephron-sparing or liver-sparing resections, and in trauma care, where preserving organ function is prioritized during critical care. Research areas focus on biomarker-based viability assessment, improved preservation solutions, extended cold storage times, and advances in ex vivo perfusion technologies.