The University of Oxford-led research, which has the potential to save more lives and reduce liver transplant waiting lists, was published today in Nature.

Rising liver disease rates have rendered the supply of viable donor organs inadequate. Many potential donor livers are deemed too high risk and can be damaged during the time they are refrigerated. Refrigeration occurs to preserve organs mid-transplant.

However, now a trial called COPE (Consortium for Organ Preservation in Europe) has found that a promising alternative lies in maintaining donor livers at body temperature, supplying the organs with oxygenated blood, medications, and nutrients—much like a patient on life support—through a process called normothermic machine perfusion.

Livers can be kept in this manner for 24 hours, and the process could one day enable the monitoring of organ viability, along with treatment and repair of organs as needed.

Measuring biomarkers of liver damage, the trial found a 50% reduction in graft injury in livers that had been perfused, compared to those kept in cold storage. In addition, in the year after transplant, the researchers found no significant differences in rates of bile duct complication, or graft and patient survival rates—as predicted by a clinically accepted biomarker—between preservation approaches.

Hynek Mergental, honorary senior lecturer at the University of Birmingham and consultant surgeon at University Hospitals Birmingham NHS Foundation’s Liver Unit led the work in Birmingham, which involved recruiting half of the 220 transplant patients who were involved in the COPE trial.

He said: “Making the most of available livers is a priority for those working in the area of transplantation.”

“This innovative, randomized trial has confirmed the benefits of the novel, dynamic organ preservation technology.”

“The trial has shown that livers transported in a perfusion machine were in a significantly better condition for transplant than those held on ice, making them more likely to produce good long-term results for the recipient.”

“The other benefit of the machine perfusion was the possibility to keep the livers up to 24 hours outside the human body, extending the times by two to three folds compared to the ice-box storage.”

“This would make the logistics of a transplant much easier, allowing surgical teams to be prepared and ready and ultimately make the whole process safer for the recipient patient. The longer preservation times and potential for greater organ numbers raise the real prospect of addressing the challenge of growing transplant waiting lists.”