Organ Utilization Rates from Non-Ideal Donors for Solid Organ Transplant in the United States.

Background: Non-ideal donors provide acceptable allografts and may expand the donor pool. This study evaluates donor utilization across solid organs over 15-years in the United States. Methods: We analyzed the OPTN STAR database to identify potential donors across three donor eras: 2005-2009, 2010-2014, and 2015-2019. Donors were analyzed by a composite Donor Utilization Score (DUS), comprised of donor age and comorbidities. Outcomes of interest were overall and organ-specific donor utilization. Descriptive analyses and multivariable logistic regression modeling were performed. p-values < 0.01 considered significant. Results: Of 132,465 donors, 32,710 (24.7%) were identified as non-ideal donors (NID), based on a DUS ≥ 3. Compared to ideal donors (ID), NID were older (median 56 years, IQR 51-64 years vs. 35 years, 22-48 years, p < 0.001) and more frequently female (44.3% vs. 39.1%, p < 0.001), Black (22.1% vs. 14.6%, p < 0.001) and obese (60.7% vs. 19.6%, p < 0.001). The likelihood of overall DBD utilization from NID increased from Era 1 to Era 2 (OR 1.227, 95% CI 1.123-1.341, p < 0.001) and Era 3 (OR 1.504, 1.376-1.643, p < 0.001), while DCD donor utilization in NID was not statistically different across Eras. Compared to Era 1, the likelihood of DBD utilization from NID for kidney transplantation was lower in Era 2 (OR 0.882, 0.822-0.946) and Era 3 (OR 0.938, 0.876-1.004, p = 0.002). The likelihood of NID utilization increased in Era 3 compared to Era 1 for livers (OR 1.511, 1.411-1.618, p < 0.001), hearts (OR 1.623, 1.415-1.862, p < 0.001), and lungs (OR 2.251, 2.011-2.520, p < 0.001). Conclusions: Using a universal definition of NID across organs, NID donor utilization is increasing; however, use of DUS may improve resource utilization in identifying donors at highest likelihood for multi-organ donation.

Donor-Dependent Variations in Systemic Oxidative Stress and Their Association with One-Year Graft Outcomes in Kidney Transplantation.

INTRODUCTION: Oxidative stress has been implicated in complications after kidney transplantation (KT), including delayed graft function (DGF) and rejection. However, its role in long-term posttransplant outcomes remains unclear. METHODS: We investigated oxidative damage and antioxidant defense dynamics, and their impact on the graft outcomes, in 41 KT recipients categorized by type of donation over 12 months. Oxidative status was determined using OxyScore and AntioxyScore indexes, which comprise several circulating biomarkers of oxidative damage and antioxidant defense. Donor types included donation after brain death (DBD [61.0%]), donation after circulatory death (DCD [26.8%]), and living donation (LD [12.1%]). RESULTS: There was an overall increase in oxidative damage early after transplantation, which was significantly higher in DCD as compared to DBD and LD recipients. The multivariate adjustment confirmed the independent association of OxyScore and type of deceased donation with DGF, donor kidney function, and induction therapy with antithymocyte globulin. There were no differences in terms of antioxidant defense. Lower oxidative damage at day 7 predicted better graft function at 1-year posttransplant only in DBD recipients. CONCLUSION: DCD induced greater short-term oxidative damage after KT, whereas the early levels of oxidative damage were predictive of the graft function 1 year after KT among DBD recipients.

Advances in lung transplantation: 60 years on.

Lung transplantation is a well-established treatment for advanced lung disease, improving survival and quality of life. Over the last 60 years all aspects of lung transplantation have evolved significantly and exponential growth in transplant volume. This has been particularly evident over the last decade with a substantial increase in lung transplant numbers as a result of innovations in donor utilization procurement, including the use donation after circulatory death and ex-vivo lung perfusion organs. Donor lungs have proved to be surprisingly robust, and therefore the donor pool is actually larger than previously thought. Parallel to this, lung transplant outcomes have continued to improve with improved acute management as well as microbiological and immunological insights and innovations. The management of lung transplant recipients continues to be complex and heavily dependent on a tertiary care multidisciplinary paradigm. Whilst long term outcomes continue to be limited by chronic lung allograft dysfunction improvements in diagnostics, mechanistic understanding and evolutions in treatment paradigms have all contributed to a median survival that in some centres approaches 10 years. As ongoing studies build on developing novel approaches to diagnosis and treatment of transplant complications and improvements in donor utilization more individuals will have the opportunity to benefit from lung transplantation. As has always been the case, early referral for transplant consideration is important to achieve best results.

Association of procurement technique with organ yield and cost following donation after circulatory death.

Donation after circulatory death (DCD) could account for the largest expansion of the donor allograft pool in the contemporary era. However, the organ yield and associated costs of normothermic regional perfusion (NRP) compared to super-rapid recovery (SRR) with ex-situ normothermic machine perfusion, remain unreported. The Organ Procurement and Transplantation Network (December 2019 to June 2023) was analyzed to determine the number of organs recovered per donor. A cost analysis was performed based on our institution's experience since 2022. Of 43 502 donors, 30 646 (70%) were donors after brain death (DBD), 12 536 (29%) DCD-SRR and 320 (0.7%) DCD-NRP. The mean number of organs recovered was 3.70 for DBD, 3.71 for DCD-NRP (P < .001), and 2.45 for DCD-SRR (P < .001). Following risk adjustment, DCD-NRP (adjusted odds ratio 1.34, confidence interval 1.04-1.75) and DCD-SRR (adjusted odds ratio 2.11, confidence interval 2.01-2.21; reference: DBD) remained associated with greater odds of allograft nonuse. Including incomplete and completed procurement runs, the total average cost of DCD-NRP was $9463.22 per donor. By conservative estimates, we found that approximately 31 donor allografts could be procured using DCD-NRP for the cost equivalent of 1 allograft procured via DCD-SRR with ex-situ normothermic machine perfusion. In conclusion, DCD-SRR procurements were associated with the lowest organ yield compared to other procurement methods. To facilitate broader adoption of DCD procurement, a comprehensive understanding of the trade-offs inherent in each technique is imperative.

Using extracorporeal membrane oxygenation in donations after cardiac death or brain death: A single-center experience and long-term outcome.

Aims: The use of extended criteria donors is a routine practice that sometimes involves extracorporeal membrane oxygenation (ECMO) in donations after cardiac death or brain death. Methods: We performed a retrospective study in a single center from January 2006 to December 2019. The study included 90 deceased donor liver transplants. The patients were divided into three groups: the donation after brain death (DBD) group (n = 58, 64.4%), the DBD with ECMO group (n = 11, 12.2%) and the donation after cardiac death (DCD) with ECMO group (n = 21, 23.3%). Results: There were no significant differences between the DBD with ECMO group and the DBD group. When comparing the DCD with ECMO group and the DBD group, there were statistically significant differences for total warm ischemia time (p < 0.001), total cold ischemia time (p = 0.023), and split liver transplantation (p < 0.001), and there was significantly poor recovery in regard to total bilirubin level (p = 0.027) for the DCD with ECMO group by repeated measures ANOVA. The 5-year survival rates of the DBD, DBD with ECMO, and DCD with ECMO groups were 78.1%, 90.9%, and 75.6%, respectively. The survival rate was not significantly different when comparing the DBD group to either the DBD with ECMO group (p = 0.435) or the DCD with ECMO group (p = 0.310). Conclusions: Using ECMO in donations after cardiac death or brain death is a good technology, and it contributed to 35.6% of the liver graft pool.

Transplant benefit-based offering of deceased donor livers in the United Kingdom.

BACKGROUND & AIMS: The National Liver Offering Scheme (NLOS) was introduced in the UK in 2018 to offer livers from deceased donors to patients on the national waiting list based, for most patients, on calculated transplant benefit. Before NLOS, livers were offered to transplant centres by geographic donor zones and, within centres, by estimated recipient need for a transplant. METHODS: UK Transplant Registry data on patient registrations and transplants were analysed to build statistical models for survival on the list (M1) and survival post-transplantation (M2). A separate cohort of registrations - not seen by the models before - was analysed to simulate what liver allocation would have been under M1, M2 and a transplant benefit score (TBS) model (combining both M1 and M2), and to compare these allocations to what had been recorded in the UK Transplant Registry. The number of deaths on the waiting list and patient life years were used to compare the different simulation scenarios and to select the optimal allocation model. Registry data were monitored, pre- and post-NLOS, to understand the performance of the scheme. RESULTS: The TBS was identified as the optimal model to offer donation after brain death (DBD) livers to adult and large paediatric elective recipients. In the first 2 years of NLOS, 68% of DBD livers were offered using the TBS to this type of recipient. Monitoring data indicate that mortality on the waiting list post-NLOS significantly decreased compared with pre-NLOS (p <0.0001), and that patient survival post-listing was significantly greater post-compared to pre-NLOS (p = 0.005). CONCLUSIONS: In the first two years of NLOS offering, waiting list mortality fell while post-transplant survival was not negatively impacted, delivering on the scheme's objectives. IMPACT AND IMPLICATIONS: The National Liver Offering Scheme (NLOS) was introduced in the UK in 2018 to increase transparency of the deceased donor liver offering process, maximise the overall survival of the waiting list population, and improve equity of access to liver transplantation. To our knowledge, it is the first scheme that offers organs based on statistical prediction of transplant benefit: the transplant benefit score. The results are important to the transplant community - from healthcare practitioners to patients - and demonstrate that, in the first two years of NLOS offering, waiting list mortality fell while post-transplant survival was not negatively impacted, thus delivering on the scheme's objectives. The scheme continues to be monitored to ensure that the transplant benefit score remains up-to-date and that signals that suggest the possible disadvantage of some patients are investigated.

Outcomes of liver transplantation for hepatocellular carcinoma in donation after circulatory death compared with donation after brain death: A systematic review and meta-analysis.

INTRODUCTION AND OBJECTIVES: Due to organ shortages, liver transplantation (LT) using donation-after-circulatory-death (DCD) grafts has become more common. There is limited and conflicting evidence on LT outcomes using DCD grafts compared to those using donation-after-brain death (DBD) grafts for patients with hepatocellular carcinoma (HCC). We aimed to summarize the current evidence on the outcomes of DCD-LT and DBD-LT in patients with HCC. MATERIALS AND METHODS: Online databases were searched for studies comparing DCD-LT and DBD-LT outcomes in patients with HCC and a meta-analysis was conducted using fixed- or random-effects models. RESULTS: Five studies involving 487 (33.4%) HCC DCD-LT patients and 973 (66.6%) DBD-LT patients were included. The meta-analysis showed comparable 1-year [relative risk (RR)=0.99, 95%CI:0.95 to 1.03, p=0.53] and 3-year [RR=0.99, 95%CI:0.89 to 1.09, p=0.79] recurrence-free survival. The corresponding 1-year [RR=0.98, 95%CI:0.93 to 1.03, p=0.35] and 3-year [RR=0.94, 95%CI:0.87 to 1.01, p=0.08] patient survival and 1-year [RR=0.91, 95%CI:0.71 to 1.16, p=0.43] and 3-year [RR=0.92, 95%CI:0.67 to 1.26, p=0.59] graft survival were also comparable. There were no significant differences between the two cohorts regarding the tumor characteristics, donor/recipient risk factors and the incidence of post-operative complications, including acute rejection, primary non-function, biliary complications and retransplantation. CONCLUSIONS: Based on the current evidence, it has been found that comparable outcomes can be achieved in HCC patients using DCD-LT compared to DBD-LT, particularly when employing good quality graft, strict donor and recipient selection, and effective surgical management. The decision to utilize DCD-LT for HCC patients should be personalized, taking into consideration the risk of post-LT HCC recurrence. (PROSPERO ID: CRD42023445812).

The positive impact of the COVID 19 pandemic on organ utilisation in liver transplantation.

Background: As the world recovers from the aftermath of devastating waves of an outbreak, the ongoing Coronavirus disease 2019 pandemic has presented a unique perspective to the transplantation community of ''organ utilisation'' in liver transplantation, a poorly defined term and ongoing hurdle in this field. To this end, we report the key metrics of transplantation activity from a high-volume liver transplantation centre in the United Kingdom over the past two years. Methods: Between March 2019 and February 2021, details of donor liver offers received by our centre from National Health Service Blood & Transplant, and of transplantation were reviewed. Differences in the activity before and after the outbreak of the pandemic, including short term post-transplant survival, have been reported. Results: The pandemic year at our centre witnessed a higher utilisation of Donation after Cardiac Death livers (80.4% vs. 58.3%, p = 0.016) with preserved United Kingdom donor liver indices and median donor age (2.12 vs. 2.02, p = 0.638; 55 vs. 57 years, p = 0.541) when compared to the pre-pandemic year. The 1- year patient survival rates for recipients in both the periods were comparable. The pandemic year, that was associated with increased utilisation of Donation after Cardiac Death livers, had an ischaemic cholangiopathy rate of 6%. Conclusions: The pressures imposed by the pandemic led to increased utilisation of specific donor livers to meet patient needs and minimise the risk of death on the waiting list, with apparently preserved early post-transplant survival. Optimum organ utilisation is a balancing act between risk and benefit for the potential recipient, and technologies like machine perfusion may allow surgeons to increase utilisation without compromising patient outcomes.

Outcomes of Heart Transplant Donation After Circulatory Death.

BACKGROUND: Heart transplantation using donation after circulatory death (DCD) allografts is increasingly common, expanding the donor pool and reducing transplant wait times. However, data remain limited on clinical outcomes. OBJECTIVES: We sought to compare 6-month and 1-year clinical outcomes between recipients of DCD hearts, most of them recovered with the use of normothermic regional perfusion (NRP), and recipients of donation after brain death (DBD) hearts. METHODS: We conducted a single-center retrospective observational study of all adult heart-only transplants from January 2020 to January 2023. Recipient and donor data were abstracted from medical records and the United Network for Organ Sharing registry, respectively. Survival analysis and Cox regression were used to compare the groups. RESULTS: During the study period, 385 adults (median age 57.4 years [IQR: 48.0-63.7 years]) underwent heart-only transplantation, including 122 (32%) from DCD donors, 83% of which were recovered with the use of NRP. DCD donors were younger and had fewer comorbidities than DBD donors. DCD recipients were less often hospitalized before transplantation and less likely to require pretransplantation temporary mechanical circulatory support compared with DBD recipients. There were no significant differences between groups in 1-year survival, incidence of severe primary graft dysfunction, treated rejection during the first year, or likelihood of cardiac allograft vasculopathy at 1 year after transplantation. CONCLUSIONS: In the largest single-center comparison of DCD and DBD heart transplantations to date, outcomes among DCD recipients are noninferior to those of DBD recipients. This study adds to the published data supporting DCD donors as a safe means to expand the heart donor pool.

DCD liver transplant in patients with a MELD over 35.

Introduction: Donation after circulatory death (DCD) liver transplantation (LT) makes up well less than 1% of all LTs with a Model for End-Stage Liver Disease (MELD)≥35 in the United States. We hypothesized DCD-LT yields acceptable ischemia-reperfusion and reasonable outcomes for recipients with MELD≥35. Methods: We analyzed recipients with lab-MELD≥35 at transplant within the UCSF (n=41) and the UNOS (n=375) cohorts using multivariate Cox regression and propensity score matching. Results: In the UCSF cohort, five-year patient survival was 85% for DCD-LTs and 86% for matched-Donation after Brain Death donors-(DBD) LTs (p=0.843). Multivariate analyses showed that younger donor/recipient age and more recent transplants (2011-2021 versus 1999-2010) were associated with better survival. DCD vs. DBD graft use did not significantly impact survival (HR: 1.2, 95%CI 0.6-2.7). The transaminase peak was approximately doubled, indicating suggesting an increased ischemia-reperfusion hit. DCD-LTs had a median post-LT length of stay of 11 days, and 34% (14/41) were on dialysis at discharge versus 12 days and 22% (9/41) for DBD-LTs. 27% (11/41) DCD-LTs versus 12% (5/41) DBD-LTs developed a biliary complication (p=0.095). UNOS cohort analysis confirmed patient survival predictors, but DCD graft emerged as a risk factor (HR: 1.5, 95%CI 1.3-1.9) with five-year patient survival of 65% versus 75% for DBD-LTs (p=0.016). This difference became non-significant in a sub-analysis focusing on MELD 35-36 recipients. Analysis of MELD≥35 DCD recipients showed that donor age of <30yo independently reduced the risk of graft loss by 30% (HR, 95%CI: 0.7 (0.9-0.5), p=0.019). Retransplant status was associated with a doubled risk of adverse event (HR, 95%CI: 2.1 (1.4-3.3), p=0.001). The rejection rates at 1y were similar between DCD- and DBD-LTs, (9.3% (35/375) versus 1,541 (8.7% (1,541/17,677), respectively). Discussion: In highly selected recipient/donor pair, DCD transplantation is feasible and can achieve comparable survival to DBD transplantation. Biliary complications occurred at the expected rates. In the absence of selection, DCD-LTs outcomes remain worse than those of DBD-LTs.

Circulating exosomes from brain death and cardiac death donors have distinct molecular and immunologic properties: A pilot study.

BACKGROUND AND AIMS: Comparison of donation after brain death (DBD) and donation after cardiac death (DCD) lung tissue before transplantation have demonstrated activation of pro-inflammatory cytokine pathway in DBD donors. The molecular and immunological properties of circulating exosomes from DBD and DCD donors were not previously described. METHODS: We collected plasma from 18 deceased donors (12 DBD and six DCD). Cytokines were analyzed by 30-Plex luminex Panels. Exosomes were analyzed for liver self-antigen (SAg), Transcription Factors and HLA class II (HLA-DR/DQ) using western blot. C57BL/6 animals were immunized with isolated exosomes to determine strength and magnitude of immune responses. Interferon (IFN)-γ and tumor necrosis factor-α producing cells were quantified by ELISPOT, specific antibodies to HLA class II antigens were measured by ELISA RESULTS: We demonstrate increased plasma levels of IFNγ, EGF, EOTAXIN, IP-10, MCP-1, RANTES, MIP-ß, VEGF, and interleukins - 6/8 in DBD plasma versus DCD. MiRNA isolated from exosome of DBD donors demonstrated significant increase in miR-421, which has been reported to correlate with higher level of Interleukin-6. Higher levels of liver SAg Collagen III (p = .008), pro-inflammatory transcription factors (NF-κB, p < .05; HIF1α, p = .021), CIITA (p = .011), and HLA class II (HLA-DR, p = .0003 and HLA-DQ, p = .013) were detected in exosomes from DBD versus DCD plasma. The circulating exosomes isolated from DBD donors were immunogenic in mice and led to the development of Abs to HLA-DR/DQ. CONCLUSIONS: This study provides potential new mechanisms by which DBD organs release exosomes that can activate immune pathways leading to cytokine release and allo-immune response.

Impact of donor sex on hepatocellular carcinoma recurrence in liver transplantation after brain death.

BACKGROUND: Hepatocellular carcinoma (HCC) is predominantly seen in males but has a better prognosis in females. No prior studies have investigated HCC recurrence based on sex combination following liver transplant donated after brain death (DBDLT). This study sought to elucidate the effects of donor and recipient sex on HCC recurrence rates. METHODS: 9232 adult recipients from the United Network for Organ Sharing (UNOS) database who underwent DBDLT for HCC from 2012 to 2018 were included. Donor-recipient pairs were divided into (1) female donor/female recipient (F-F) (n = 1089); (2) male donor/female recipient (M-F) (n = 975); (3) female donor/male recipient (F-M) (n = 2691); (4) male donor/male recipient (M-M) (n = 4477). The primary prognostic outcome was HCC recurrence. A multivariable competing risk regression analysis was used to assess prognostic influences. RESULTS: The median recipient age and model for end-stage liver disease (MELD) scores were similar among the four groups. Livers of male recipients demonstrated greater in size and number of HCC (both p-values were <.0001). There was also a higher rate of vascular invasion in male recipients compared to female (p < .0001). Competing risk analyses showed that the cumulative HCC recurrence rate was significantly lower in the M-F group (p = .013). After adjusting for tumor characteristics, liver grafts from male donors were associated with a lower HCC recurrence rate in female recipients (HR: .62 95%CI: .42-.93) (p = .021). CONCLUSION: In DBDLT, male donor to female recipient pairing exhibited lower HCC recurrence rates. SUMMARY: Lowest rates of HCC recurrence were confirmed among the female recipients of male donor grafts group in the deceased donor LT cohort. A competing risk multivariable regression analysis demonstrated that male donor sex was significantly associated with low HCC recurrence in female but not male recipients.

Outcomes of lung and liver transplantation after simultaneous recovery using abdominal normothermic regional perfusion in donors after the circulatory determination of death versus donors after brain death.

Normothermic regional perfusion (NRP) in controlled donation after the circulatory determination of death (cDCD) is a growing preservation technique for abdominal organs that coexists with the rapid recovery of lungs. We aimed to describe the outcomes of lung transplantation (LuTx) and liver transplantation (LiTx) when both grafts are simultaneously recovered from cDCD donors using NRP and compare them with grafts recovered from donation after brain death (DBD) donors. All LuTx and LiTx meeting these criteria during January 2015 to December 2020 in Spain were included in the study. Simultaneous recovery of lungs and livers was undertaken in 227 (17%) donors after cDCD with NRP and 1879 (21%) DBD donors (P < .001). Primary graft dysfunction grade-3 within the first 72 hours was similar in both LuTx groups (14.7% cDCD vs. 10.5% DBD; P = .139). LuTx survival at 1 and 3 years was 79.9% and 66.4% in cDCD vs. 81.9% and 69.7% in DBD (P = .403). The incidence of primary nonfunction and ischemic cholangiopathy was similar in both LiTx groups. Graft survival at 1 and 3 years was 89.7% and 80.8% in cDCD vs. 88.2% and 82.1% in DBD LiTx (P = .669). In conclusion, the simultaneous rapid recovery of lungs and preservation of abdominal organs with NRP in cDCD donors is feasible and offers similar outcomes in both LuTx and LiTx recipients to transplants using DBD grafts.

Paving the Way for Personalized Medicine in First Kidney Transplantation: Interest of a Creatininemia Latent Class Analysis in Early Post-transplantation.

Plasma creatinine is a marker of interest in renal transplantation but data on its kinetics in the first days following transplantation are scarce. The aim of this study was to identify clinically relevant subgroups of creatinine trajectories following renal transplantation and to test their association with graft outcome. Among 496 patients with a first kidney transplant included in the French ASTRE cohort at the Poitiers University hospital, 435 patients from donation after brain death were considered in a latent class modeling. Four distinct classes of creatinine trajectories were identified: "poor recovery" (6% of patients), "intermediate recovery" (47%), "good recovery" (10%) and "optimal recovery" (37%). Cold ischemia time was significantly lower in the "optimal recovery" class. Delayed graft function was more frequent and the number of hemodialysis sessions was higher in the "poor recovery" class. Incidence of graft loss was significantly lower in "optimal recovery" patients with an adjusted risk of graft loss 2.42 and 4.06 times higher in "intermediate recovery" and "poor recovery" patients, respectively. Our study highlights substantial heterogeneity in creatinine trajectories following renal transplantation that may help to identify patients who are more likely to experience a graft loss.

The international experience of in-situ recovery of the DCD heart: a multicentre retrospective observational study.

Background: Heart transplantation is an effective treatment offering the best recovery in both quality and quantity of life in those affected by refractory, severe heart failure. However, transplantation is limited by donor organ availability. The reintroduction of heart donation after the circulatory determination of death (DCD) in 2014 offered an uplift in transplant activity by 30%. Thoraco-abdominal normothermic regional perfusion (taNRP) enables in-situ reperfusion of the DCD heart. The objective of this paper is to assess the clinical outcomes of DCD donor hearts recovered and transplanted from donors undergoing taNRP. Method: This was a multicentre retrospective observational study. Outcomes included functional warm ischaemic time, use of mechanical support immediately following transplantation, perioperative and long-term actuarial survival and incidence of acute rejection requiring treatment. 157 taNRP DCD heart transplants, performed between February 2, 2015, and July 29, 2022, have been included from 15 major transplant centres worldwide including the UK, Spain, the USA and Belgium. 673 donations after the neurological determination of death (DBD) heart transplantations from the same centres were used as a comparison group for survival. Findings: taNRP resulted in a 23% increase in heart transplantation activity. Survival was similar in the taNRP group when compared to DBD. 30-day survival was 96.8% ([92.5%-98.6%] 95% CI, n = 156), 1-year survival was 93.2% ([87.7%-96.3%] 95% CI, n = 72) and 5-year survival was 84.3% ([69.6%-92.2%] 95% CI, n = 13). Interpretation: Our study suggests that taNRP provides a significant boost to heart transplantation activity. The survival rates of taNRP are comparable to those obtained for DBD transplantation in this study. The similar survival may in part be related to a short warm ischaemic time or through a possible selection bias of younger donors, this being an uncontrolled observational study. Therefore, our study suggests that taNRP offers an effective method of organ preservation and procurement. This early success of the technique warrants further investigation and use. Funding: None of the authors have a financial relationship with a commercial entity that has an interest in the subject.

A Review of Machine Perfusion Strategies in Liver Transplantation.

The acceptance of liver transplantation as the standard of care for end-stage liver diseases has led to a critical shortage of donor allografts. To expand the donor organ pool, many countries have liberalized the donor criteria including extended criteria donors and donation after circulatory death. These marginal livers are at a higher risk of injury when they are preserved using the standard static cold storage (SCS) preservation techniques. In recent years, research has focused on optimizing organ preservation techniques to protect these marginal livers. Machine perfusion (MP) of the expanded donor liver has witnessed considerable advancements in the last decade. Research has showed MP strategies to confer significant advantages over the SCS techniques, such as longer preservation times, viability assessment and the potential to recondition high risk allografts prior to implantation. In this review article, we address the topic of MP in liver allograft preservation, with emphasis on current trends in clinical application. We discuss the relevant clinical trials related to the techniques of hypothermic MP, normothermic MP, hypothermic oxygenated MP, and controlled oxygenated rewarming. We also discuss the potential applications of ex vivo therapeutics which may be relevant in the future to further optimize the allograft prior to transplantation.

Extended criteria brain-dead organ donors: Prevalence and impact on the utilisation of livers for transplantation in Brazil.

BACKGROUND: Despite its association with higher postoperative morbidity and mortality, the use of extended criteria donor (ECD) livers for transplantation has increased globally due to the high demand for the procedure. AIM: To investigate the prevalence of ECD in donation after brain death (DBD) and its impact on organ acceptance for transplantation. METHODS: Retrospective analysis of DBD organ offers for liver transplantation between 2017 and 2020 in a high-volume transplant centre. The incidence of the Eurotransplant risk factors to define an ECD (ET-ECD) among DBD donors and the likelihood of organ acceptance over the years were analysed. The relationship between organ refusal for transplantation, the occurrence, and the number of ET-ECD was assessed by simple and multiple logistic regression adjustment. RESULTS: A total of 1619 organ donors were evaluated. Of these, 78.31% (n = 1268) had at least one ET-ECD criterion. There was an increase in the acceptance of ECD DBD organs for transplantation (1 criterion: from 23.40% to 31.60%; 2 criteria: from 13.10% to 27.70%; 3 criteria: From 6.30% to 13.60%). For each addition of one ET-ECD variable, the estimated chance of organ refusal was 64.4% higher (OR 1.644, 95%CI 1.469-1.839, P < 0.001). Except for the donor serum sodium > 165 mmol/L (P = 0.310), all ET-ECD criteria increased the estimated chance of organ refusal for transplantation. CONCLUSION: A high prevalence of ECD DBD was observed. Despite the increase in their utilisation, the presence and the number of extended donor criteria were associated with an increased likelihood of their refusal for transplantation.