Citations

Background: Normothermic machine perfusion (NMP) may reduce preservation injury in donation-after-circulatory-death (DCD) liver transplantation, but its association with patient-centered recovery and longer-term graft survival remains uncertain. Study Design: We retrospectively analyzed 306 consecutive adult DCD liver transplant recipients at a single center from January 2019 through December 2022, comparing NMP (n=95) with static cold storage (SCS; n=211). The primary endpoint was days alive and out of hospital at 365 days (DAOH365). Quasi-Poisson regression evaluated factors associated with DAOH365, and Cox regression evaluated graft survival. Propensity-matched and calendar-year sensitivity analyses assessed measured confounding. Results: Median DAOH365 was 357.0 (352.0, 360.0) days with NMP versus 353.0 (336.0, 359.0) with SCS (p<0.001), but preservation strategy was not independently associated with DAOH365 (adjusted rate ratio 1.02; p=0.331). NMP recipients had less early allograft dysfunction (35.8% vs 59.7%; p<0.001), ischemic cholangiopathy (4.2% vs 23.7%; p<0.001), and retransplantation within 2 years (0.0% vs 6.6%; p=0.007). Two-year patient survival did not differ significantly. NMP was associated with improved twoF-year graft survival (HR 2.9, 95% CI 1.23–6.87; p=0.015), an association maintained in propensity-matched and calendar-year sensitivity analyses. Adjusted total 1-year costs did not differ (p=0.512). Conclusions: In this single-center DCD cohort, NMP was associated with superior 2-year graft survival but not independently with DAOH365. These hypothesis-generating findings support multicenter prospective evaluation of NMP using both graft survival and patient-centered recovery endpoints.

ABSTRACT Background With increasing use of donation after circulatory death (DCD) donor grafts, the need for accurate risk‐stratification tools in liver transplantation has become critical. Machine perfusion has been shown to improve both graft and patient survival. However, existing prediction models were developed in the static cold storage (SCS) era and their accuracy when using machine perfusion remains unknown. Our study aims to study if current scoring systems can predict graft and patient survival for DCD livers preserved using normothermic machine perfusion (NMP). Methods This was a retrospective study of patient and graft survival in a two‐center U.S. DCD NMP cohort ( n = 532) between January 2022 and December 2024. Predicted graft and patient survival rates were obtained from established risk scoring systems, including the United Kingdom DCD risk score (UK‐DCD), Early Allograft Dysfunction (EAD) Olthoff score, Liver Graft Assessment Following Transplantation (L‐GrAFT 7 ) score, Donor Risk Index (DRI), Balance of Risk (BAR) score, and Survival Outcomes Following Liver Transplant (SOFT) score. Model discrimination was assessed using receiver operating characteristic (ROC) curves (C‐statistics). Survival outcomes across risk strata were estimated and compared using Kaplan‐Meier (KM) analysis. Results Across scoring systems, predicted survival consistently underestimated actual graft and patient survival in the NMP DCD cohort. The DRI, SOFT, EAD and L‐GrAFT 7 did not demonstrate predictive value. UK‐DCD predicted ≤85% and <40% 1‐year graft survival for its high‐risk and “futile” groups, whereas observed rates were 93.7% and 86.8%. BAR low‐risk predicted >60% 5‐year survival but 94.2% was observed; the high‐risk group predicted <60% and observed was 53.3%. Despite underestimations and generally poor C‐statistics, in KM stratification, high‐risk groups still showed statistical differences in the UK‐DCD categories ( p = 0.007), and in SOFT score groups ( p < 0.001). No statistical difference was seen in BAR ( p = 0.36), DRI ( p = 0.36), EAD ( p = 0.12), or L‐GrAFT 7 ( p = 0.75). Conclusion Existing liver transplant risk scores show limited predictive value for donor‐related risk factors in the NMP era, whereas recipient‐related factors remain somewhat predictive, despite overestimating risk. Early allograft dysfunction metrics were not reliable predictors of short or long‐term outcomes. Future risk models should integrate machine‐perfusion parameters and refined donor variables to reflect outcomes more accurately in contemporary DCD liver transplantation.

ABSTRACT Despite the annual increase in liver transplants, a persistent disparity between suitable donors and recipients continues to challenge the transplant community. The introduction of machine perfusion emerged as a novel approach to organ preservation. This technique, which utilizes extended criteria donor grafts, is expected to reduce rejection rates and expand the donor pool. Its principle, like that of any ex vivo machine perfusion, is based on the continuous supply of nutrients and oxygen to maintain cellular metabolism while interrupting anaerobic processes. This helps prevent conditions such as ischemia-reperfusion injury, early graft dysfunction, and ischemic cholangiopathy, which can lead to graft loss and the need for retransplantation. There are two main modes of ex vivo machine perfusion: hypothermic and normothermic, differentiated by the operating temperature. Utilizing ex situ perfusion machines presents a promising opportunity to increase liver graft usage and reduce waitlist times. However, it is crucial to evaluate how much this technology would raise the overall cost of transplants. In Brazil, implementing a machine perfusion program may encounter unique challenges not seen in other countries. These challenges include limited access to the healthcare system for high-risk liver transplant candidates, long waiting lists, inadequate support for organ donors, reliance solely on deceased brain-dead donors, since donation after cardiac death is not ethically accepted, and geographical barriers.

Objective: To determine whether normothermic machine perfusion (NMP) mitigates the historical survival disadvantage of donation after circulatory death (DCD) liver transplantation compared with donation after brain death (DBD) livers. Summary Background Data: NMP has improved outcomes in DCD LT compared with static cold storage (SCS), but whether it eliminates the historical disparity relative to DBD transplantation remains uncertain. Methods: We performed a retrospective cohort study of adult LT at a high-volume US center between 2019 and 2024. Outcomes of DCD-NMP grafts were compared with DCD-SCS, DBD-SCS, and DBD-NMP grafts. Primary outcomes were 1-year graft and patient survival. Secondary outcomes included early allograft dysfunction (EAD), hepatic artery thrombosis (HAT), primary nonfunction (PNF), biliary anastomotic strictures (BAS), and ischemic cholangiopathy (IC). Results: Among 1338 liver transplants (DBD-SCS n=527; DBD-NMP n=142; DCD-SCS n=255; DCD-NMP n=414), DCD-NMP grafts had a significantly higher donor risk profile ( P <0.001) yet demonstrated survival comparable to DBD transplantation. One-year graft survival was 94% for DCD-NMP versus 93% for DBD grafts and 86% for DCD-SCS, and 1-year patient survival was 98% for DCD-NMP versus 94% to 95% for DBD grafts and 93% for DCD-SCS. In adjusted models, DCD-SCS was associated with increased hazards of graft loss (adjusted hazard ratio: 2.48; P <0.001) and death (adjusted hazard ratio: 2.39; P =0.004), whereas DBD groups did not differ from DCD-NMP. Incidence of EAD was lower with DCD-NMP (21.7%) than DCD-SCS (50.2%) and similar to DBD grafts (21.1%–26.4%); HAT and PNF were rare (≤1.3%). At 1 year, BAS occurred in 36% of DCD grafts versus 17% to 23% of DBD grafts. IC occurred in 7.7% of DCD-NMP compared with 22% of DCD-SCS and ≤1.5% of DBD grafts. Retransplantation due to IC was infrequent overall (1.3%), but more common in DCD-SCS (4.7%) than DCD-NMP (1.0%) and DBD grafts (≤0.4%). Conclusions: NMP enables safe utilization of DCD liver allografts and achieves graft and patient survival comparable to DBD LT, mitigating the historical disadvantage of DCD grafts. These findings support routine integration of NMP into clinical practice and efforts to standardize its implementation.

Donation after circulatory death (DCD) liver transplants (LTs) are associated with increased risk of post-LT acute kidney injury (AKI). This retrospective study aimed to examine the effect of continuous normothermic machine perfusion (NMP) on the incidence and stage of AKI in DCD LT. The incidence of AKI within 48 hours was compared between 507 NMP-DCD and 472 static cold storage (SCS)-DCD LT transplanted between January 1, 2016, and December 31, 2024. AKI developed in 337 (34%) patients. On univariate analysis, AKI rate was lower in NMP-DCD compared with SCS-DCD (28% vs. 41%, p <0.001). Stages 2 and 3 AKI at 48 hours and renal replacement therapy (RRT) within the first 3 weeks were also lower in NMP-DCD compared with SCS-DCD ( p <0.001). After adjusting for multiple recipient, donor, and intraoperative factors using multivariate logistic regression, NMP-DCD was independently associated with a 37% lower odds of AKI (aOR: 0.63, CI: 0.46–0.85, p =0.003) and 55% lower odds of stages 2 and 3 AKI (aOR: 0.45, CI: 0.29–0.69, p <0.001) compared with SCS-DCD. To mitigate for the era effect and other unmeasured confounders, an inverse probability of treatment weighting (IPTW) analysis was performed using a propensity score model with average treatment effect (ATE). After weighting for multiple factors, NMP-DCD was associated with lower odds of AKI at 48 hours (OR: 0.65, CI: 0.53–0.81, p =0.001), stages 2 and 3 AKI at 48 hours (OR: 0.60, CI: 0.42–0.85, p =0.02), and RRT at day 7 (OR: 0.31, CI: 0.13–0.65, p =0.003) compared with SCS-DCD. In conclusion, compared with SCS-DCD, NMP-DCD was independently associated with lower odds of AKI at 48 hours, of stages 2 and 3 AKI at 48 hours from LT, and of RRT requirement at day 7 from LT, an effect that extended for the first 3 post-LT weeks.

Donation after circulatory death (DCD) livers increasingly use machine perfusion (MP). This study evaluates MP’s impact on older DCD livers based on data from the United Network for Data Sharing, covering all first adult DCD liver transplants (2016–2025). The cohort, divided into pre-MP and MP eras (separated by the FDA approval of the first normothermic MP platform in 2021), showed accelerated growth in DCD liver transplants during the MP era. Donors ≥60 rose 7.8-fold, including donors ≥70 (a USA first). By 2025, DCD livers accounted for 43.2%, with 61.35% from donors ≥50. Normothermic regional perfusion (NRP) (3.0%–21.7%), NMP (2.3%–35.6%), and sequential NRP-NMP (0.1%–19.2%) increased significantly (p &lt; 0.001). The MP era was associated with a decrease in median waitlist time from 112 to 62 days (p &lt; 0.001). Early graft survival was similar across ages. For ages 50–59, 1- and 3-year survivals were 87.9%/78.4% pre-MP and 90.1%/78.8% in the MP era. For 60–69, survival was 85.0%/80.6% pre-MP and 90.0%/71.3% in the MP era. DCD LTs for ≥70 were limited to the MP era with 87.8% 1-year survival. Multivariable Cox regression showed that static cold storage (HR = 1.19), donor age 50–69 versus 18–49, and recipient age (HR = 1.04) increased the risk of graft loss after adjustment. MP is associated with an increased number of older DCD liver transplants and acceptable early graft survival.

Purpose of review Living donor transplantation is the optimal treatment for end-stage renal disease and end-stage liver disease. For the recipient, the benefits of living donation include improved duration of graft survival compared to deceased donation and avoidance of lengthy waiting time and risks of dialysis. For transplant centers, a robust living donor program results in consistent transplant case volumes, daytime cases and a decreased reliance on potentially unfavorable allocation policy changes. Transplant programs require a playbook of actionable initiatives based on consensus best practices and peer-reviewed data to optimize opportunities to increase living donor evaluation and surgery within current legal and policy frameworks. Relevant findings Strategies to increase center living donor volume include utilization of culturally competent transplant education and outreach, development of living donor champion programs, wider utilization of financial assistance programs available to living donors, increased enrollment in paired donor exchange services and adaptation of modern evidence-based selection and evaluation criteria. Summary Understanding the current landscape of living donor transplantation and exploring areas of innovation is imperative to a center's ability to continue to serve the full spectrum of patients with end stage organ disease to the best of our collective ability.

Limited information on the business practices of liver transplant (LT) centers worldwide has been published. Characterizing this data could help identify best practices as well as opportunities for improvement. As such, the International Liver Transplant Society (ILTS) Business Practice Committee conducted a global online survey of LT centers, which was sent to the ILTS membership. Questions focused on 5 main domains: transplant practice and volumes, workforce, finances, quality assessment and performance improvement, and overall program function. Data was compared across program geographic regions and transplant volume. A total of 89 discrete centers were represented, of which 76.4% were academic/university-affiliated, and about one-third each were from Europe (36.0%) and North America (31.5%). The top 3 problems programs reported were finances/funding (60.7%), adequate program support/guidance (48.3%), and transplant volumes (43.8%). In all, 59.6% of respondents felt their salary was undercompensated, consistent across geographic regions. In addition, 69.7% felt their center was not adequately funded to meet program goals, with programs in Europe (N=28/32, 87.5%) and Oceania (N=2/3, 66.7%) most impacted. Transplant surgeon retainment was noted as more difficult for lower volume programs (<50 liver transplants/year, N=13/31). Nearly half (42.7%) of all programs felt under-resourced to provide high-quality care, and the majority (80.9%) felt there was room for growth and improvement under their current model. While international concerns varied widely among LT centers, inadequate salary and center funding, low transplant and referral volumes, and staff retainment were persistent themes. Focusing on adopting region-specific best practices and developing transplant systems of care that focus on these elements is critical to provide optimal care to LT patients worldwide.