It is safe for patients to receive a donor liver that has been intentionally preserved overnight using machine perfusion to enable a daytime transplant.
This is shown by a study performed at the University Medical Center Groningen (UMCG) in The Netherlands, including transplants using all types of donor organs. The post-transplant outcomes are at least as good as those for livers that were not treated with machine perfusion, or were treated for only a short time, prior to transplantation.
Analysis of all liver transplants in two year
It had previously been shown that the machine perfusion technique developed at the UMCG made it possible to better schedule liver transplants to daytime. "We subsequently adopted this as standard of care following our earlier study based on 24 liver transplants," explains Vincent de Meijer, liver transplant surgeon and head of the UMCG Transplant Center. "We have now conducted a large follow-up study on this method. We analyzed all transplanted livers in 2023 and 2024. That amounted to 175 liver transplants following the introduction of the new perfusion technique. We compared these with the 155 transplants from two years prior, during which we did not yet routinely perfuse donor livers overnight using hypothermic machine perfusion but instead transplanted them immediately."
90% of liver transplants now performed during the day
The study shows that the number of liver transplants performed during the day at the UMCG has increased dramatically. De Meijer: 'In 2021 and 2022, approximately 50% of liver transplants took place during the day, but with the new technology, this has risen to nearly 90% in 2023 and 2024. This means we have to conduct liver transplants at the last minute much less often. That could have consequences for other already scheduled surgeries, which sometimes had to be postponed as a result. Prolonged hypothermic machine perfusion has increased flexibility, our medical staff experience less stress and patients can be better cared for. It also makes complex combined transplants possible, such as heart-liver or lung-liver transplants, which in the Netherlands are performed only in Groningen. No one wants to go back to the old situation."
Quality of Care
The study shows that extending the preservation time with hypothermic machine perfusion to avoid nighttime liver transplants is safe for all types of donor livers. De Meijer: "One year after the transplant, we examined all possible outcomes in patients: complications, survival, blood loss, and length of hospital stay. For all these factors, the quality following intentionally extended preservation with machine perfusion is at least as good as that of transplants in which the liver was not treated with machine perfusion or was treated for only a short time. This means not only that we can now plan better, but also that patients can expect the same quality of care.'
Safe for all types of donor livers
An important aspect of the study is that it now also examined livers from donors who died following cardiac arrest. Donor livers can come from patients who have died from brain death, but increasingly, liver transplants are being performed using livers from patients who have died from cardiac arrest. This is the first study worldwide to demonstrate that these organs can also be preserved longer using cooled machine perfusion to avoid nighttime transplants, and function just as well in the recipient.
Successful transplant after 24 hours on the pump
Furthermore, the study shows that it is entirely possible to preserve donor livers even longer using hypothermic machine perfusion. "We successfully transplanted a liver even after more than 31 hours outside the body, including 24 hours on the pump. That is a world record for this technique," said De Meijer. The study's results were published today in the authoritative scientific journal JAMA Network Open.
Hopefully adopted in more centers
De Meijer and his team are very proud of the study's results: "It confirms that machine perfusion makes it possible to preserve donor livers longer, schedule transplants more effectively, reduce time pressure and stress among physicians, and achieve exceptionally good outcomes for patients. Every patient deserves a well-equipped surgical team, and I hope that, following the UMCG's lead, this technique will be introduced in more centers!"
Hypothermic oxygenated machine perfusion
Instead of the traditional method, in which organs are stored only in a cold box filled with ice, the UMCG uses a perfusion machine that actively supplies the liver with oxygen at a temperature of ten degrees prior to transplantation. This ensures that the liver is in much better condition before it is transplanted into the recipient's body.
