July 12, 2024
Late allocation liver grafts provide patients awaiting liver transplantation additional opportunities. Transplant surgeons at Mayo Clinic in Arizona are accepting and successfully using late allocation grafts with good outcomes.
In the U.S. in recent years, there's been an increase in both the number of liver transplants performed as well as the number of livers recovered with intent for transplant but ultimately not transplanted.
Various factors limit a patient's access to liver transplant, such as the ongoing organ shortage and differences in acceptance patterns at transplant centers.
Innovative options
With little information about post-transplant outcomes specific to these grafts, researchers in transplant surgery at Mayo Clinic in Arizona sought to assess characteristics and outcomes of late allocation (LA) allografts.
In a study published in Liver Transplantation in December 2023, Mayo Clinic transplant surgeons found that the use of post-cross clamp liver allograft offers allow for additional liver transplant opportunities.
"Liver offer acceptance and transplant rates vary across different transplant centers, adding to the existing challenge of organ scarcity. Transplanting liver allografts after the time of recovery, also known as post-clamp or late allocation offers, can be challenging, but provide more opportunities for recipients awaiting liver transplant. Late allocation liver offers continue to be at a high risk for nonutilization due to logistical challenges." says Caroline C. Jadlowiec, M.D., a transplant surgeon and the surgical director of the Kidney Transplant Program at Mayo Clinic in Arizona, and one of the study's authors.
Challenges using LA livers
- Needing to quickly reinterpret available data.
- Managing possible obstacles such as distance, timing and transport.
- Working with unknown variables contributing to intraoperative decline.
- Extended cold ischemia time (CIT).
Despite hurdles, there are good outcomes using late allocation grafts. "Even though these liver allografts require more complicated coordination and longer periods of CIT, they achieve comparable results to standard allocation liver allografts," says Dr. Jadlowiec.
The study focused on LA liver allografts transplanted at Mayo Clinic in Arizona between 2015 and 2021. Of the 895 liver-alone transplants performed at the clinic, 101 (11.3%) were performed using late allocation offers.
All late allocation grafts in the study were originally allocated and declined by other transplant centers. The liver allografts underwent static cold storage. Machine perfusion was not used for this study period.
Key findings
- Between 2015 and 2021, 11.3% of liver transplants at Mayo Clinic in Arizona occurred because of LA offers.
- The allografts were mostly donation after brain death. The donors were younger and the majority underwent a preimplantation biopsy that was normal.
- There were no differences in intensive care unit and hospital lengths of stay, patient survival, and graft survival, despite longer CIT and more allograft dysfunction.
- The late allocation liver allografts had an average of two hours of additional CIT compared with liver allografts offered through standard allocation.
Late graft success
The goal is to help minimize nonuse of all potential organs. The Mayo Clinic Transplant Center in Arizona says timely communication between the recovery team, organ procurement organization (OPO) and a potential recipient is critical to allow for expedited assessment and logistical planning.
Most late allocation offers in this cohort came from regional and national OPOs. Utilizing late allocation grafts successfully relies on geography and transportation availability.
Educating patients
Mayo Clinic in Arizona's innovative thinking in organ acceptance involves planning and preparation. "Providing patients with education on donor characteristics and allocation possibilities allows them to be prepared," says Dr. Jadlowiec. "It's also important to have timely access to waitlist patients who are ready to come in for transplant particularly when there are late allocation liver offers."
What's next?
It's essential to improve allocation policies specific to LA offers and share best practices between transplant centers and OPOs. "The Mayo Clinic Transplant Center in Arizona has continued to further expand opportunities for liver transplant, both through use of late allocation offers as well as with use of allografts from donation after circulatory death donors and machine perfusion," says Dr. Jadlowiec. "More opportunities exist for patients awaiting liver transplant to further increase access to transplant."
For more information
Jadlowiec C, et al. Liver transplant outcomes using late allocation grafts. Liver Transplantation. 2023;29:1323.
Refer a patient to Mayo Clinic.