Citations

Background. Normothermic regional perfusion (NRP) has emerged as a vital technique in organ procurement, particularly in donation after circulatory death (DCD) cases, offering the potential to optimize organ utilization and improve posttransplant outcomes. Recognizing its significance, the American Society of Transplant Surgeons (ASTS) convened a work group to develop standardized recommendations for abdominal NRP in the United States. Methods. The workgroup, comprising experts in NRP, DCD, and transplantation, formulated recommendations through a collaborative process involving revisions and approvals by relevant committees and the ASTS council. Four key areas were identified for standardization: Preprocedure communication, NRP procedure, Terminology and documentation, and Mentorship/credentialing. Results. The recommendations encompass a range of considerations, including preprocedure communication protocols to facilitate informed decision-making by transplant centers and organ procurement organizations, procedural guidelines for NRP teams, uniform terminology to clarify the NRP process, and standards for mentorship and credentialing of NRP practitioners. Specific recommendations address logistical concerns, procedural nuances, documentation requirements, and the importance of ongoing quality assurance. Conclusions. The standardized recommendations for abdominal NRP presented in this article aim to ensure consistency, safety, and efficacy in the organ procurement process. By establishing clear protocols and guidelines, the ASTS seeks to enhance organ utilization, honor donor wishes, and uphold public trust in the donation process. Implementation of these recommendations can contribute to the advancement of NRP practices and improve outcomes for transplant recipients.

The number of kidney after liver transplants (KALT) increased after the implementation of the United Network of Organ Sharing (UNOS) safety net policy, but the effects of the policy on KALT outcomes remain unknown. Using the UNOS database, we identified KALT between 60 and 365 days from liver transplant from January 1, 2010, to December 31, 2020. The main outcome was 1- and 3-year patient, liver, and kidney graft survival. Secondary outcomes included 6-month and 1-year acute rejection (AR) of liver and kidney, and 1-year kidney allograft function. Of the 256 KALT, 90 were pre-policy and 166 post-policy. Compared to pre-policy, post-policy 1- and 3-year liver graft survival was higher (54% and 54% vs. 86% and 81%, respectively, p <0.001), while 1- and 3-year kidney graft survival (99% and 75% vs. 92% and 79%, respectively, p =0.19), and 1- and 3-year patient survival (99% and 99% vs. 95% and 89%, respectively, p =0.11) were not significantly different. Subgroup analysis revealed similar trends in patients with and without renal failure at liver transplant. Liver AR at 6 months was lower post-policy (6.3% vs. 18.3%, p =0.006) but was similar (10.5% vs. 13%, p =0.63) at 1 year. Kidney AR was unchanged post-policy at 6 months and 1 year. Creatinine at 1 year did not differ post-policy versus pre-policy (1.4 vs. 1.3 mg/dL, p =0.07) despite a higher proportion of deceased donors, higher Kidney Donor Profile Index, and longer kidney cold ischemia time post-policy ( p <0.05 for all). This 3-year follow-up after the 2017 UNOS policy revision demonstrated that the safety net implementation has resulted in improved liver outcomes for patients who underwent KALT with no increased AR of the liver or the kidney allografts.

In situ abdominal normothermic regional perfusion (A-NRP) has been used for liver transplantation (LT) with donation after circulatory death (DCD) liver grafts in Europe with excellent results; however, adoption of A-NRP in the United States has been lacking. The current report describes the implementation and results of a portable, self-reliant A-NRP program in the United States. Isolated abdominal in situ perfusion with an extracorporeal circuit was achieved through cannulation in the abdomen or femoral vessels and inflation of a supraceliac aortic balloon and cross-clamp. The Quantum Transport System by Spectrum was used. The decision to use livers for LT was made through an assessment of perfusate lactate (q15min). From May to November 2022, 14 A-NRP donation after circulatory death procurements were performed by our abdominal transplant team (N = 11 LT, N = 20 kidney transplants, and 1 kidney-pancreas transplant). The median A-NRP run time was 68 minutes. None of the LT recipients had post-reperfusion syndrome, nor were there any cases of primary nonfunction. All livers were functioning well at the time of maximal follow-up with zero cases of ischemic cholangiopathy. The current report describes the feasibility of a portable A-NRP program that can be used in the United States. Excellent short-term post-transplant results were achieved with both livers and kidneys procured from A-NRP.

While adoption of machine perfusion technologies into clinical practice in the United States has been much slower than in Europe, recent changes in the transplant landscape as well as device availability following FDA approval have paved the way for rapid growth. Machine perfusion may provide one mechanism to maximize the utilization of potential donor liver grafts. Indeed, multiple studies have shown increased organ utilization with the implementation of technologies such as ex-situ normothermic machine perfusion (NMP), ex-situ hypothermic machine perfusion (HMP) and in-situ normothermic regional perfusion (NRP). The current review describes the history and development of machine perfusion utilization in the Unites States along with future directions. It also describes the differences in landscape between Europe and the United States and how this has shaped clinical application of these technologies.

BACKGROUND: Liver transplantation (LT) is an effective strategy for patients with unresectable hepatocellular carcinoma (HCC). To qualify for standardized LT model for end-stage liver disease exception points, the United Network for Organ Sharing National Liver Review Board (NLRB) requires that the presenting and final HCC tumor burden be within the University of California San Francisco criteria, which were recently expanded (within expanded UCSF [W-eUCSF]). Current NLRB criteria may be too restrictive because it has been shown previously that the initial burden does not predict LT failure when tumors downstage to UCSF. This study aims to assess LT outcomes for HCC initially presenting beyond expanded UCSF (B-eUCSF) criteria in a large multicenter collaboration. STUDY DESIGN: Comparisons of B-eUCSF and W-eUCSF candidates undergoing LT at seven academic institutions between 2001 and 2017 were made from a multi-institutional database. Survival outcomes were compared by Kaplan-Meier and Cox regression analyses. RESULTS: Of 1,846 LT recipients with HCC, 86 (5%) met B-eUCSF criteria at initial presentation, with the remainder meeting W-eUCSF criteria. Despite differences in tumor burden, B-eUCSF candidates achieved comparable 1-, 5- and 10-year overall (89%, 70%, and 55% vs 91%, 74%, and 60%, respectively; p = 0.2) and disease-free (82%, 60%, and 53% vs 89%, 71%, and 59%, respectively; p = 0.07) survival to patients meeting W-eUCSF criteria after LT. Despite increased tumor recurrence in B-eUCSF vs W-eUCSF patients (24% vs 10%, p = 0.0002), post-recurrence survival was similar in both groups (p = 0.69). CONCLUSION: Transplantation for patients initially presenting with HCC B-eUSCF criteria offers a survival advantage similar to those with tumors meeting W-eUCSF criteria at presentation. The current NLRB policy is too stringent, and considerations to expand criteria should be discussed.