Benefits of Hypothermic Oxygenated Perfusion
Organ preservation is evolving beyond the limitations of traditional cold storage. Hypothermic oxygenated perfusion (HOPE) is emerging as a promising approach to maintaining donor organ viability while enabling greater flexibility across the transplantation journey.
The Science of HOPE
For decades, the standard way to move a donor organ from one body to another has been remarkably low-tech: cool it down, pack it in ice, and race the clock. Static cold storage has saved countless lives, but it was never designed to protect an organ. It was designed to slow it down. And slowing an organ down is not the same as keeping it alive.
Hypothermic Oxygenated Machine Perfusion, or HOPE, changes that equation. By continuously circulating a cold, oxygenated solution through the organ during transport and storage, HOPE does something the ice box never could. It keeps the organ metabolically supported, actively protected, and ready to work the moment it reaches the recipient.
At Vascular Perfusion Solutions, HOPE is the foundation of the VP.S ENCORE®, our portable perfusion platform. Here is the science behind why it matters, and what it means for patients waiting for a transplant.
The Problem with Cold Alone
When an organ is placed on ice, its metabolism slows, but it does not stop. The cellular machinery keeps turning over, quietly, in the dark, without oxygen to sustain it.
Inside every cell, the mitochondria are the power plants. During cold storage without oxygen, they can no longer generate energy normally, and a molecule called succinate begins to build up. Think of it as metabolic debt accumulating silently while the organ sits on ice.
The damage does not show up during storage. It shows up at the worst possible moment, when the organ is reconnected to blood flow in the recipient. That sudden return of oxygen ignites the accumulated succinate all at once, releasing a burst of reactive oxygen species that injures the very organ the surgeon just implanted. This is ischemia-reperfusion injury, and it is one of the central reasons organs fail early, function poorly, or are declined for transplant altogether.
In other words, the longer an organ waits on ice, the more metabolic debt it carries, and the harder it gets hit the instant it wakes up.
What HOPE Actually Does
HOPE addresses the problem at its source, at the level of the mitochondria.
By delivering oxygen to the organ while it stays cold, HOPE lets the mitochondria work through that accumulated succinate gently and gradually, while metabolic demand is still low. Energy stores are partially recharged. The cell’s internal balance is restored. The mitochondrial membrane, the structure that determines whether a cell lives or dies at reperfusion, stays protected.
The result is that when the organ is finally warmed and reconnected to blood flow, the destructive burst of reactive oxygen species is dramatically blunted. The organ does not wake up wrecked. It wakes up primed.
The simplest way to say it: HOPE recharges the organ’s power plants so that reperfusion protects instead of punishes.
This is not theoretical. The mechanism is well characterized in the scientific literature, and the clinical evidence has followed. In liver transplantation, randomized controlled trials have shown that HOPE reduces early graft injury and improves outcomes compared to cold storage. In kidney, portable hypothermic perfusion has quietly become a practical standard, and oxygenation adds a mechanistic upside on top of it. Across organs, the pattern is consistent. The biology rewards cold and oxygen. The trial data rewards cold and oxygen.
The Benefits, in Plain Terms
Healthier organs at the finish line. By blunting ischemia-reperfusion injury, HOPE helps organs arrive in better condition, which is directly linked to better function and fewer early complications after transplant.
More time, and more flexibility. HOPE extends the safe preservation window beyond what cold storage allows. That means fewer rushed logistics, wider geographic reach between donor and recipient, and more room for the transplant team to plan rather than scramble.
More usable organs. A large share of donated organs are never transplanted because they are considered too marginal to survive the journey. By protecting organs during transport, HOPE can make it possible to safely use organs that would otherwise be discarded, including those from donation after circulatory death (DCD) and extended-criteria donors. Every additional organ recovered is a life that might otherwise not have been saved.
Protection without the complexity. Some perfusion systems try to keep an organ fully warm and functioning during transport, which requires blood, elaborate hardware, and a heavy logistical footprint. HOPE achieves its protective effect at cold temperatures, which allows for a simpler, lighter, and more affordable approach. That difference is not a compromise. It is a strategic advantage for the centers and programs that need this technology most.
Why This Matters to Us
The VP.S ENCORE® was built to deliver the science of HOPE in a form the transplant community can actually use everywhere, not just at the largest and best-funded centers. Portable. Versatile across organs. Designed with pediatric patients in mind. Built at a cost structure that expands access rather than restricting it.
That focus is not an accident. It is the whole point. The promise of better preservation only matters if it reaches the patients who are too often left waiting, including the most vulnerable patients, including pediatric patients who face the steepest barriers to a life-saving transplant.
Better science should mean more transplants, for more people, in more places. That is what HOPE makes possible, and that is what we are building.
Selected References
The science of HOPE rests on a well-established body of peer-reviewed evidence. A few of the foundational studies:
- Chouchani ET, Pell VR, Gaude E, et al. Ischaemic accumulation of succinate controls reperfusion injury through mitochondrial ROS. Nature. 2014;515(7527):431-435.
- Martin JL, Costa ASH, Gruszczyk AV, et al. Succinate accumulation drives ischaemia-reperfusion injury during organ transplantation. Nature Metabolism. 2019;1(10):966-974.
- van Rijn R, Schurink IJ, de Vries Y, et al. Hypothermic machine perfusion in liver transplantation, a randomized trial. New England Journal of Medicine. 2021;384(15):1391-1401.
- Schlegel A, Mueller M, Muller X, et al. A multicenter randomized-controlled trial of hypothermic oxygenated perfusion (HOPE) for human liver grafts before transplantation. Journal of Hepatology. 2023;78(4):783-793.
- Moers C, Smits JM, Maathuis MH, et al. Machine perfusion or cold storage in deceased-donor kidney transplantation. New England Journal of Medicine. 2009;360(1):7-19.
Redefining Donor Organ Viability With Hypothermic Oxygenated Machine Perfusion
Delivering HOPE to more patients with the VP.S ENCORE®.