Using old liver grafts for liver transplantation: Where are the limits?

Focusing on Ischemic Reperfusion Injury in the New Era of Dynamic Machine Perfusion in Liver Transplantation

Liver transplantation is the most effective treatment for end-stage liver disease. Transplant indications have been progressively increasing, with a huge discrepancy between the supply and demand of optimal organs. In this context, the use of extended criteria donor grafts has gained importance, even though these grafts are more susceptible to ischemic reperfusion injury (IRI). Hepatic IRI is an inherent and inevitable consequence of all liver transplants; it involves ischemia-mediated cellular damage exacerbated upon reperfusion and its severity directly affects graft function and post-transplant complications. Strategies for organ preservation have been constantly improving since they first emerged. The current gold standard for preservation is perfusion solutions and static cold storage. However, novel approaches that allow extended preservation times, organ evaluation, and their treatment, which could increase the number of viable organs for transplantation, are currently under investigation. This review discusses the mechanisms associated with IRI, describes existing strategies for liver preservation, and emphasizes novel developments and challenges for effective organ preservation and optimization.

Evaluating the outcomes of donor-recipient age differences in young adults undergoing liver transplantation

The current liver allocation system may be disadvantaging younger adult recipients as it does not incorporate the donor-recipient age difference. Given the longer life expectancy of younger recipients, the influences of older donor grafts on their long-term prognosis should be elucidated. This study sought to reveal the long-term prognostic influence of the donor-recipient age difference in young adult recipients. Adult patients who received initial liver transplants from deceased donors between 2002 and 2021 were identified from the UNOS database. Young recipients (patients 45 years old or below) were categorized into 4 groups: donor age younger than the recipient, 0-9 years older, 10-19 years older, or 20 years older or above. Older recipients were defined as patients 65 years old or above. To examine the influence of the age difference in long-term survivors, conditional graft survival analysis was conducted on both younger and older recipients. Among 91,952 transplant recipients, 15,170 patients were 45 years old or below (16.5%); these were categorized into 6,114 (40.3%), 3,315 (21.9%), 2,970 (19.6%), and 2,771 (18.3%) for groups 1-4, respectively. Group 1 demonstrated the highest probability of survival, followed by groups 2, 3, and 4 for the actual graft survival and conditional graft survival analyses. In younger recipients who survived at least 5 years post-transplant, inferior long-term survival was observed when there was an age difference of 10 years or above (86.9% vs. 80.6%, log-rank p <0.01), whereas there was no difference in older recipients (72.6% vs. 74.2%, log-rank p =0.89). In younger patients who are not in emergent need of a transplant, preferential allocation of younger aged donor offers would optimize organ utility by increasing postoperative graft survival time.

Impact of Older Donor Age on Recipient and Graft Survival After LDLT: The US Experience

BACKGROUND

The impact of selecting older donors for living donor liver transplantation (LDLT) in the United States is incompletely studied, particularly in light of the recent expansion of LDLT nationally.

METHODS

Adult LDLTs from January 01, 2005 to December 31, 2019 were identified using the United Network for Organ Sharing database. Multivariable Cox models evaluated living donor (LD) age as a predictor of LDLT recipient and graft survival. The impact of increasing donor age on recipient outcomes was compared between LD and deceased donor recipients. Donor postoperative outcomes were evaluated.

RESULTS

There were 3539 LDLTs at 65 transplant centers during the study period. Despite the recent expansion of LDLT, the proportion of LDs aged ≥50 y was stable. There were no clinically significant differences in recipient or donor characteristics by LD age group. LD age ≥50 y was associated with an adjusted hazard ratio of 1.49 ( P = 0.012) for recipient survival and 1.61 ( P < 0.001) for graft survival (vs LDs aged 18-29 y). The negative impact of increasing donor age on graft survival was more profound after LDLT than deceased donor liver transplantation (interaction P = 0.019). There was a possible increased rate of early donor biliary complications for donors >55 y (7.1% versus 3.1% for age <40 y; P = 0.156).

CONCLUSIONS

Increasing LD age is associated with decreased recipient and graft survival, although older donors still largely yield acceptable outcomes. Donor outcomes were not clearly impacted by increasing age, though this warrants further study.

Mitochondria and Cancer Recurrence after Liver Transplantation—What Is the Benefit of Machine Perfusion?

Tumor recurrence after liver transplantation has been linked to multiple factors, including the recipient’s tumor burden, donor factors, and ischemia-reperfusion injury (IRI). The increasing number of livers accepted from extended criteria donors has forced the transplant community to push the development of dynamic perfusion strategies. The reason behind this progress is the urgent need to reduce the clinical consequences of IRI. Two concepts appear most beneficial and include either the avoidance of ischemia, e.g., the replacement of cold storage by machine perfusion, or secondly, an endischemic organ improvement through perfusion in the recipient center prior to implantation. While several concepts, including normothermic perfusion, were found to reduce recipient transaminase levels and early allograft dysfunction, hypothermic oxygenated perfusion also reduced IRI-associated post-transplant complications and costs. With the impact on mitochondrial injury and subsequent less IRI-inflammation, this endischemic perfusion was also found to reduce the recurrence of hepatocellular carcinoma after liver transplantation. Firstly, this article highlights the contributing factors to tumor recurrence, including the surgical and medical tissue trauma and underlying mechanisms of IRI-associated inflammation. Secondly, it focuses on the role of mitochondria and associated interventions to reduce cancer recurrence. Finally, the role of machine perfusion technology as a delivery tool and as an individual treatment is discussed together with the currently available clinical studies.

An Update on Usage of High-Risk Donors in Liver Transplantation

The ideal management for end stage liver disease, acute liver failure, and hepatocellular carcinoma (HCC), within specific criteria, is liver transplantation (LT). Over the years, there has been a steady increase in the candidates listed for LT, without a corresponding increase in the donor pool. Therefore, due to organ shortage, it has been substantially difficult to reduce waitlist mortality among patients awaiting LT. Thus, marginal donors such as elderly donors, steatotic donors, split liver, and donors after cardiac death (DCD), which were once not commonly used, are now considered. Furthermore, it is encouraging to see the passing of Acts, such as the HIV Organ Policy Equity (HOPE) Act, enabling further research and development in utilizing HIV grafts. Subsequently, the newer antivirals have aided in successful post-transplant period, especially for hepatitis C positive grafts. However, currently, there is no standardization, and protocols are center specific in the usage of marginal donors. Therefore, studies with longer follow ups are required to standardize its use.

Expression of MICA in Zero Hour Biopsies Predicts Graft Survival After Liver Transplantation

In search for novel biomarkers to assess graft quality, we investigated whether defined candidate genes are predictive for outcome after liver transplantation (LT).

Zero-hour liver biopsies were obtained from 88 livers. Gene expression of selected candidate markers was analyzed and correlated with clinical parameters as well as short and long-term outcomes post LT. Whereas both, the calculated Eurotransplant Donor-Risk-Index and the donor body mass index, had either a poor or no predictive value concerning serum levels indicative for liver function (ALT, AST, GGT, bilirubin) after 6 months, chronological donor age was weakly predictive for serum bilirubin (AUC=0.67). In contrast, the major histcompatibility complex class I related chain A (MICA) mRNA expression demonstrated a high predictive value for serum liver function parameters revealing an inverse correlation (e.g. for ALT: 3 months p=0.0332; 6 months p=0.007, 12 months 0.0256, 24 months p=0.0098, 36 months, p=0.0153) and proved significant also in a multivariate regression model. Importantly, high expression of MICA mRNA revealed to be associated with prolonged graft survival (p=0.024; log rank test) after 10 years of observation, whereas low expression was associated with the occurrence of death in patients with transplant related mortality (p=0.031). Given the observed correlation with short and long-term graft function, we suggest MICA as a biomarker for pre-transplant graft evaluation.

Extended criteria grafts and emerging therapeutics strategy in liver transplantation. The unstable balance between damage and repair

Due to increasing demand for donor organs, "extended criteria" donors are increasingly considered for liver transplantation, including elderly donors and donors after cardiac death. The grafts of this subgroup of donors share a major risk to develop significant features of ischemia reperfusion injury, that may eventually lead to graft failure. Ex-situ machine perfusion technology has gained much interest in liver transplantation, because represents both a useful tool for improving graft quality before transplantation and a platform for the delivery of therapeutics directly to the organ. In this review, we survey ongoing clinical evidences supporting the use of elderly and DCD donors in liver transplantation, and the underlying mechanistic aspects of liver aging and ischemia reperfusion injury that influence graft quality and transplant outcome. Finally, we highlight evidences in the field of new therapeutics to test in MP in the context of recent findings of basic and translational research.

The Utility of Extended Criteria Donor Livers in High Acuity Liver Transplant Recipients

BACKGROUND

Although the use of extended criteria donor (ECD) liver allografts has gained momentum as a potential method by which to expand the donor pool, their use largely remains relegated to low acuity liver transplant (LT) recipients. Thus, we sought to examine whether such grafts also have utility in high acuity (Model for End-Stage Liver Disease [MELD] ≥ 35) recipients.

STUDY DESIGN

Extended criteria donors were defined as donor age > 60 years, hepatitis C virus positive donor, split livers, livers with cold ischemia time > 12 h, donor after cardiac death livers, or having macrosteatosis > 30%. Outcomes were compared between standard liver (SL) and ECD grafts in recipients with MELD ≥ 35.

RESULTS

Of 225 patients, 46 (20.4%) received an ECD liver and 179 (79.6%) received a SL. Extended criteria donor graft recipients had significantly higher levels of post-LT maximal transaminases and rate of early allograft dysfunction. Nonetheless, high acuity ECD graft recipients had similar short- and long-term patient survival compared to SL recipients, with 1-,3-, and 5-year survivals of 86.9%, 82.3%, 79.3% and 86.9%, 80.5%, and 75.4%, respectively (P = .674). There were also no significant differences in graft survival or rejection-free survival between the 2 groups.

CONCLUSION

The lack of inferior patient/graft survival among high acuity ECD graft recipients suggests that ECD livers present a viable method by which to expand the donor pool for this group of patients.

Ex vivo machine perfusion: current applications and future directions in liver transplantation

BACKGROUND

Liver transplantation is the only curative treatment option for end-stage liver disease; however, its use remains limited due to a shortage of suitable organs. In recent years, ex vivo liver machine perfusion has been introduced to liver transplantation, as a means to expand the donor organ pool.

PURPOSE

To present a systematic review of prospective clinical studies on ex vivo liver machine perfusion, in order to assess current applications and highlight future directions.

METHODS

A systematic literature search of both PubMed and ISI web of science databases as well as the ClinicalTrials.gov registry was performed.

RESULTS

Twenty-one articles on prospective clinical trials on ex vivo liver machine perfusion were identified. Out of these, eight reported on hypothermic, eleven on normothermic, and two on sequential perfusion. These trials have demonstrated the safety and feasibility of ex vivo liver machine perfusion in both standard and expanded criteria donors. Currently, there are twelve studies enrolled in the clinicaltrials.gov  registry, and these focus on use of ex vivo perfusion in extended criteria donors and declined organs.

CONCLUSION

Ex vivo liver machine perfusion seems to be a suitable strategy to expand the donor pool for liver transplantation and holds promise as a platform for reconditioning diseased organs.

Incidence and risk factors of primary non-function after liver transplantation using grafts from uncontrolled donors after circulatory death

BACKGROUND

Graft primary non-function (PNF) is the most severe complication after orthotopic liver transplantation (OLT) and is frequently associated with livers from uncontrolled circulatory death (uDCD).

METHODS

We reviewed retrospectively the incidence, risk factors, and outcome of patients showing PNF after receiving uDCD liver grafts. The series comprises 75 OLT performed during 11 years.

RESULTS

The incidence of PNF using uDCD livers was 8%. We compared patients who developed PNF (n = 6) vs. patients without PNF (n = 69). Mean pump flow of donors during normothermic regional perfusion (NRP) was significantly lower in PNF (p = .032). Day 1 post-OLT levels of transaminases and the incidence of renal complications and postoperative mortality were also significantly higher in the PNF group, but 5-year patient survival was similar in both groups (66.7% in PNF and 68.5% in non-PNF). All PNF patients underwent re-OLT, and 2 died. PNF incidence has decreased in the last 5-years. Binary logistic regression analysis confirmed final ALT value >4 times the normal value as risk factor for PNF, and median donor pump flow >3700 ml/min as protective effect.

CONCLUSIONS

Adequate donor pump flow during NRP was a protective.

Evaluation of hepatic steatosis before liver transplantation in ex vivo by volumetric quantitative PDFF-MRI

PURPOSE

Over the last two decades, extended criteria have promoted an increased number of donor livers available for liver transplantation. But posttransplant graft loss is still a major concern. Macrovesicular hepatic steatosis (MHS) is recognized as the most significant prognostic histologic parameter in predicting posttransplant graft loss. We aimed to evaluate the utility of ex vivo volumetric quantitative MRI for quantifying MHS before liver transplantation using proton density fat-fraction (PDFF-MRI) histogram analysis.

METHODS

PDFF-MRI was performed at 3.0T in 40 livers. We obtained histogram parameters of whole-liver volume of interest, including the mean, median, 5th, 10th, 25th, 75th, 90th, and 95th percentile PDFF; skewness; kurtosis; entropy; and volume.

RESULTS

Livers from 40 cadaveric donors were included, and histologic ex vivo fat quantification was available for 33 livers. Ten livers had MHS and 23 had normal fat content. The MHS group had higher mean, median, 5th, 10th, 25th, 75th, 90th, and 95th percentile PDFF, and entropy than the group with normal fat content (P < .05). Median PDFF had greater area under the curve value than other parameters. Mean PDFF showed an excellent correlation with entropy and a moderate correlation with MHS quantification on histology.

CONCLUSIONS

Ex vivo volumetric quantitative PDFF-MRI histogram analysis is a very useful and noninvasive method to detect MHS before liver transplantation. Median PDFF was the best predictor of the presence of MHS. Entropy is a very promising parameter.

Organ Restoration With Normothermic Machine Perfusion and Immune Reaction

Liver transplantation is the only recognized effective treatment for end-stage liver disease. However, organ shortages have become the main challenge for patients and physicians within the transplant community. Waiting list mortality remains an issue with around 10% of patients dying whilst waiting for an available organ. The post-transplantation period is also associated with an adverse complication rate for these specific cohorts of high-risk patients, particularly regarding patient and graft survival. Ischaemia reperfusion injury (IRI) has been highlighted as the mechanism of injury that increases parenchymal damage, which eventually lead to significant graft dysfunction and other poor outcome indicators. The consequences of IRI in clinical practice such as reperfusion syndrome, primary non-function of graft, allograft dysfunction, ischaemic biliary damage and early biliary complications can be life-threatening. IRI dictates the development of a significant inflammatory response that drives the pathway to eventual cell death. The main mechanisms of IRI are mitochondrial damage due to low oxygen tension within the hepatic micro-environment and severe adenosine triphosphate (ATP) depletion during the ischaemic period. After the restoration of normal blood flow, this damage is further enhanced by reoxygenation as the mitochondria respond to reperfusion by releasing reactive oxygen species (ROS), which in turn activate Kupffer cells within the hepatic micro-environment, leading to a pro-inflammatory response and eventual parenchymal cell apoptosis and associated tissue degradation. Machine perfusion (MP) is one emergent strategy considered to be one of the most important advances in organ preservation, restoration and transplantation. Indeed, MP has the potential to rescue frequently discarded organs and has been shown to limit the extent of IRI, leading to suppression of the deleterious pro-inflammatory response. This immunomodulation reduces the prevalence of allograft rejection, the use of immunosuppression therapy and minimizes post-transplant complications. This review aims to update the current knowledge of MP with a focus on normothermic machine liver perfusion (NMLP) and its potential role in immune response pathways.

Liver Transplantation Using Uncontrolled Donors After Circulatory Death: A 10-year Single-center Experience

BACKGROUND

One method for increasing the donor pool for orthotopic liver transplantations (OLTs) is to use uncontrolled donation after circulation death (uDCDs).

METHODS

From January 2006 to December 2016, we performed 75 OLTs using uDCD livers. The control group comprised a sample of 265 OLTs using livers of donations after brain death (DBDs). A comparative study was performed.

RESULTS

Of 256 potential uDCD donors cannulated, 75 (29.3%) livers were accepted for OLT. The amount of hemoderivatives transfused was significantly higher in the uDCD group. The rate of primary nonfunction was also significantly higher (P = 0.031) in uDCD recipients (8%) than DBD recipients (1.5%). The overall rate of biliary complications was significantly higher (P = 0.001) in uDCD recipients (23 cases, 30.6%) than DBD recipients (28 cases, 10.6%). In the uDCD group, 1-, 3-, and 5-year patient survival rates were 82.7%, 73%, and 71.5%, respectively; in the DBD group, they were 89%, 83.7%, and 78.8%, respectively (P = 0.180). In the uDCD group, 1-, 3-, and 5-year graft survival rates were 73.3%, 65.1%, and 63.6%, respectively; in the DBD group, they were 87.1%, 81.9%, and 76.5%, respectively (P = 0.013). Multivariate analysis showed that independent risk factors for patient and graft survival were intraoperative transfusion of >6 units of packed red blood cell concentrates and recipients who were older than 60 years.

CONCLUSIONS

Although graft survival is significantly lower using uDCD livers, 5-year patient survival in recipients of DBD and uDCD livers is similar. After careful selection, the livers of uDCD can be selectively used for OLT.

Transplanting Marginal Organs in the Era of Modern Machine Perfusion and Advanced Organ Monitoring

Organ transplantation is undergoing profound changes. Contraindications for donation have been revised in order to better meet the organ demand. The use of lower-quality organs and organs with greater preoperative damage, including those from donation after cardiac death (DCD), has become an established routine but increases the risk of graft malfunction. This risk is further aggravated by ischemia and reperfusion injury (IRI) in the process of transplantation. These circumstances demand a preservation technology that ameliorates IRI and allows for assessment of viability and function prior to transplantation. Oxygenated hypothermic and normothermic machine perfusion (MP) have emerged as valid novel modalities for advanced organ preservation and conditioning. Ex vivo prolonged lung preservation has resulted in successful transplantation of high-risk donor lungs. Normothermic MP of hearts and livers has displayed safe (heart) and superior (liver) preservation in randomized controlled trials (RCT). Normothermic kidney preservation for 24 h was recently established. Early clinical outcomes beyond the market entry trials indicate bioenergetics reconditioning, improved preservation of structures subject to IRI, and significant prolongation of the preservation time. The monitoring of perfusion parameters, the biochemical investigation of preservation fluids, and the assessment of tissue viability and bioenergetics function now offer a comprehensive assessment of organ quality and function ex situ. Gene and protein expression profiling, investigation of passenger leukocytes, and advanced imaging may further enhance the understanding of the condition of an organ during MP. In addition, MP offers a platform for organ reconditioning and regeneration and hence catalyzes the clinical realization of tissue engineering. Organ modification may include immunological modification and the generation of chimeric organs. While these ideas are not conceptually new, MP now offers a platform for clinical realization. Defatting of steatotic livers, modulation of inflammation during preservation in lungs, vasodilatation of livers, and hepatitis C elimination have been successfully demonstrated in experimental and clinical trials. Targeted treatment of lesions and surgical treatment or graft modification have been attempted. In this review, we address the current state of MP and advanced organ monitoring and speculate about logical future steps and how this evolution of a novel technology can result in a medial revolution.

Anaesthesia for Liver Transplantation: An Update

Liver transplantation (LT) is a challenging surgery performed on patients with complex physiology profiles, complicated by multi-system dysfunction. It represents the treatment of choice for end-stage liver disease. The procedure is performed under general anaesthesia, and a successful procedure requires an excellent understanding of the patho-physiology of liver failure and its implications. Despite advances in knowledge and technical skills and innovations in immunosuppression, the anaesthetic management for LT can be complicated and represent a real challenge. Monitoring devices offer crucial information for the successful management of patients. Hemodynamic instability is typical during surgery, requiring sophisticated invasive monitoring. Arterial pulse contour analysis and thermo-dilution techniques (PiCCO), rotational thromboelastometry (RO-TEM), transcranial doppler (TCD), trans-oesophageal echocardiography (TEE) and bispectral index (BIS) have been proven to be reliable monitoring techniques playing a significant role in decision making. Anaesthetic management is specific according to the three critical phases of surgery: pre-anhepatic, anhepatic and neo-hepatic phase. Surgical techniques such as total or partial clamping of the inferior vena cava (IVC), use of venovenous bypass (VVBP) or portocaval shunts have a significant impact on cardiovascular stability. Post reperfusion syndrome (PRS) is a significant event and can lead to arrhythmias and even cardiac arrest.

Biliary Complications After Liver Transplantation From Uncontrolled Donors After Circulatory Death: Incidence, Management, and Outcome

The utilization of livers from donation after uncontrolled circulatory death (uDCD) increases the availability of liver grafts, but it is associated with a higher incidence of biliary complications (BCs) and lower graft survival than those organs donated after brain death. From January 2006 to December 2016, we performed 75 orthotopic liver transplantations (OLTs) using uDCD livers. To investigate the relationship of BCs with the use of uDCD OLT, we compared patients who developed BCs (23 patients) with those who did not (non-BC group, 43 patients) after excluding cases of hepatic artery thrombosis (a known cause of BC) and primary nonfunction. The groups had similar uDCD donor maintenance, donor and recipient characteristics, and perioperative morbidity/mortality rates, but we observed a higher rate of hepatocellular carcinoma and hepatitis C virus in the non-BC group. Percutaneous transhepatic biliary dilation, endoscopic retrograde cholangiopancreatography dilation, Roux-en-Y hepaticojejunostomy (HJ), a T-tube, and retransplantation were used for BC management. In the BC group, 1-, 3-, and 5-year patient survival rates were 91.3%, 69.6%, and 65.2%, respectively, versus 77.8%, 72.9%, and 72.9%, respectively, in the non-BC group (P = 0.89). However, 1-, 3-, and 5-year graft survival rates were 78.3%, 60.9%, and 56.5%, respectively, in the BC group versus 77.8%, 72.9%, and 72.9%, respectively, in the non-BC group (P = 0.38). Multivariate analysis did not indicate independent risk factors for BC development. In conclusion, patient and graft survival rates were generally lower in patients who developed BCs but not significantly so. These complications were managed in the majority of patients through radiological dilation, endoscopic dilation, or Roux-en-Y HJ. Retransplantation is necessary in rare cases after the failure of biliary dilation or surgical procedures.

[High donor age for liver transplantation : Tackling organ scarcity in Germany]

BACKGROUND

Liver transplantation is the only curative treatment option for patients with end-stage liver disease; however, the 40% decline of available organ donors in recent years in Germany necessitates the optimization of available resources and possibly extending the criteria to older donors.

MATERIAL AND METHODS

All 2652 livers made available to the Charité Universitätsmedizin Berlin from 2010 to 2016 were retrospectively analyzed and the clinical outcome of 526 liver transplantations during this time frame were evaluated.

RESULTS

The median age of donors of transplanted organs increased from 49.3 years in 2010 to 57.3 years in 2016 (p = 0.02). Organs from donors ≥65 years were more frequently discarded than organs from younger donors (n = 344, 18.4% vs. n = 220, 28.1%; p = 0.005). Moreover, the older donors had higher rates of diabetes mellitus and hepatic steatosis. Organs from older donors had a higher donor risk index (2.8 vs. 2.2; p < 0.001) and were transplanted more often in patients with preserved liver function and hepatocellular carcinoma and liver cirrhosis (n = 121, 74.7% of indications). The 3‑year survival after liver transplantation from donors ≥65 and ≥80 years old was not significantly reduced in comparison to younger donors; however, there was an increased retransplantation rate (28.6%; p = 0.005) after transplantation of organs from donors ≥80 years old.

CONCLUSION

Despite conservative organ acceptance there were higher rates of retransplantation after transplantation from very old donors. In the light of an increasing scarcity of suitable organs this mandates caution and highlights the need for adequate assessment instruments for marginal donor organs before transplantation.

The Impact of Steatosis on the Outcome of Liver Transplantation: A Meta-Analysis

Background and Aims

Liver transplantation is one of the most effective treatments for end-stage liver disease as well as for cases of acute liver failure. Facing organ donor shortage, liver transplant teams had to use marginal organs. Thus, increasing availability is a key concern of donor liver grafts including steatotic livers. However, the use of steatotic liver is still controversial. The aim of this systematic review and meta-analysis was to analyze the impact of steatosis on the outcome of liver transplantation.

Methods

We searched PubMed, Cochrane Library, Embase, Web of knowledge, and so on for studies published through May 31, 2018, in which patients experienced liver transplantation using fatty liver. All studies extracted outcome indicators, and we draw conclusions by contrasting outcome indicators in different groups of steatosis. Odds ratios and 95% confidence intervals were calculated. P<0.05 was considered as statistically significant difference.

Results

19 publications were included. There was no significant difference between the group of no steatosis and mild group in primary nonfunction rate (P=0.605) or early graft dysfunction rate (P=0.44). The PNF rate was significantly higher in moderate group (P=0.003) and severe group (P <0.001) compared with that in no steatosis group. The same results were seen in early graft dysfunction rate. However, graft survival rate and patient survival rate did not differ between groups.

Conclusions

Livers with mild steatosis, even with moderate or severe steatosis, could be suitable donor under strict control of transplant conditions.

Liver Donation From Marginal Donors: To Donate or Not to Donate?

OBJECTIVES

Livers from deceased donors compose nearly 30% of all organ transplants, and about 700 liver transplants are carried out per year. Marginal livers (extended-criteria donors), however, are not usually accepted by recipient teams, and there is only one center for these procedures in Iran. The final decision is made according to criteria that are much more conservative than other globally accepted ones.

MATERIALS AND METHODS

To find significant differences and construct an algorithm to predict the future of marginal livers (before transfer of donors to our organ procurement unit), successfully donated and unsuccessfully donated livers divided into 2 age groups were compared in terms of age, sex, body mass index, liver function tests, significant medical disorders, and preretrieval liver sonography report.

RESULTS

In the first age group (50-59 years old), there were 88 successful donors and 27 unsuccessful cases (due to 3 reasons: positive virology tests, death before retrieval, and ruled out by surgeons in the operating room). In the second age group (? 60 years old), there were 45 successful donors and 11 unsuccessful cases. The results showed that there were no differences between successful and unsuccessful cases regarding age and liver sonography results; however, sex, body mass index, liver function tests, and previous medical disorder were different between groups. Donors in both age groups were mostly male (60% and 73%); however, surprisingly, most unsuccessful cases were female (56.6% and 57%). Donors had generally lower body mass index (2 numerical difference), better liver function tests, and less risk factors (heart disease, diabetes mellitus, fatty liver, and chronic alcohol consumption).

CONCLUSIONS

Before transfer of marginal liver donors to the organ procurement unit for further evaluation and organ retrieval, one must consider that age is just a number and the presence of other comorbidities can have more decisive roles on liver quality.

Analyzing predictors of graft survival in patients undergoing liver transplantation with donors aged 70 years and over

AIM

To increase the number of available grafts.

METHODS

This is a single-center comparative analysis performed between April 1986 and May 2016. Two hundred and twelve liver transplantation (LT) were performed with donors ≥ 70 years old (study group). Then, we selected the first cases that were performed with donors < 70 years old immediately after the ones that were performed with donors ≥ 70 years old (control group).

RESULTS

Graft and patient survivals were similar between both groups without increasing the risk of complications, especially primary non-function, vascular complications and biliary complications. We identified 5 risk factors as independent predictors of graft survival: recipient hepatitis C virus (HCV)-positivity [hazard ratio (HR) = 2.35; 95% confidence interval (CI): 1.55-3.56; P = 0.00]; recipient age (HR = 1.04; 95%CI: 1.02-1.06; P = 0.00); donor age X model for end-stage liver disease (D-MELD) (HR = 1.00; 95%CI: 1.00-1.00; P = 0.00); donor value of serum glutamic-pyruvic transaminase (HR = 1.00; 95%CI: 1.00-1.00; P = 0.00); and donor value of serum sodium (HR = 0.96; 95%CI: 0.94-0.99; P = 0.00). After combining D-MELD and recipient age we obtained a new scoring system that we called DR-MELD (donor age X recipient age X MELD). Graft survival significantly decreased in patients with a DR-MELD score ≥ 75000, especially in HCV patients (77% vs 63% at 5 years in HCV-negative patients, P = 0.00; and 61% vs 25% at 5 years in HCV-positive patients; P = 0.00).

CONCLUSION

A DR-MELD ≥ 75000 must be avoided in order to obtain the best results in LT with donors ≥ 70 years old.

Combined Hypothermic and Normothermic Machine Perfusion Improves Functional Recovery of Extended Criteria Donor Livers

Hypothermic oxygenated perfusion (HOPE) and normothermic perfusion are seen as distinct techniques of ex situ machine perfusion of the liver. We aimed to demonstrate the feasibility of combining both techniques and whether it would improve functional parameters of donor livers into transplant standards. Ten discarded human donor livers had either 6 hours of normothermic perfusion (n = 5) or 2 hours of HOPE followed by 4 hours of normothermic perfusion (n = 5). Liver function was assessed according to our viability criteria; markers of tissue injury and hepatic metabolic activity were compared between groups. Donor characteristics were comparable. During the hypothermic perfusion phase, livers down-regulated mitochondrial respiration (oxygen uptake, P = 0.04; partial pressure of carbon dioxide perfusate, P = 0.04) and increased adenosine triphosphate levels 1.8-fold. Following normothermic perfusion, those organs achieved lower tissue expression of markers of oxidative injury (4-hydroxynonenal, P = 0.008; CD14 expression, P = 0.008) and inflammation (CD11b, P = 0.02; vascular cell adhesion molecule 1, P = 0.05) compared with livers that had normothermic perfusion alone. All livers in the combined group achieved viability criteria, whereas 40% (2/5) in the normothermic group failed (P = 0.22). In conclusion, this study suggests that a combined protocol of hypothermic oxygenated and normothermic perfusions might attenuate oxidative stress, tissue inflammation, and improve metabolic recovery of the highest-risk donor livers compared with normothermic perfusion alone.

Results After Implementing a Program of Intensive Care to Facilitate Organ Donation

A program of intensive care to facilitate organ donation (ICOD) represents one of the ways to increase donation rate following brain death (BD).

OBJECTIVES

To analyze the impact and cost-effectiveness of setting up an ICOD strategy.

METHOD

Retrospective cases of BD donors from the Spanish region La Rioja were included, after implementation of an ICOD program (2011-2016). This was activated in cases of devastating neurologic injury where treatment had been rejected following therapeutic futility criteria. Follow-up of kidney and liver transplant patients with the obtained grafts was carried out.

RESULTS

A total of 134 potential donors were admitted to intensive care unit (ICU), of whom 106 were selected under the ICOD strategy. BD was diagnosed in 108 cases (25 conventional donors, 83 ICOD donors). A total of 21.6% of potential ICOD donors did not evolve to BD, subsequently dying in the ICU. ICOD cases accounted for more than 50% of donors each year. This cohort had an average stay of 2.4 days in the ICU and accounted for a small proportion of total ICU admissions. A total of 68 (81.9%) ICOD donors were finally effective and 146 grafts were extracted, the majority being abdominal organs (liver and kidney). Probability of survival 1 year after liver transplant (ICOD donor) was 90.9%, with 1 case of primary graft failure. Survival 1 year after kidney transplant (ICOD donor) was 92.7%. No differences were detected in survival rates of kidney and liver transplant patients regarding donor type (ICOD vs conventional).

CONCLUSIONS

Implementation of an ICOD program allows an increase in the pool of valid and quality grafts for transplant as well as implying a minimum consumption of intensive medicine resources. The results in transplant patients support this strategy.

Ischemia-Reperfusion Injury in Aged Livers-The Energy Metabolism, Inflammatory Response, and Autophagy

Because of the lack of adequate organs, the number of patients with end-stage liver diseases, acute liver failure or hepatic malignancies waiting for liver transplantation is constantly increasing. Accepting aged liver grafts is one of the strategies expanding the donor pool to ease the discrepancy between the growing demand and the limited supply of donor organs. However, recipients of organs from old donors may show an increased posttransplantation morbidity and mortality due to enhanced ischemia-reperfusion injury. Energy metabolism, inflammatory response, and autophagy are 3 critical processes which are involved in the aging progress as well as in hepatic ischemia-reperfusion injury. Compared with young liver grafts, impairment of energy metabolism in aged liver grafts leads to lower adenosine triphosphate production and an enhanced generation of free radicals, both aggravating the inflammatory response. The aggravated inflammatory response determines the extent of hepatic ischemia-reperfusion injury and augments the liver damage. Autophagy protects cells by removal of damaged organelles, including dysfunctional mitochondria, a process impaired in aging and involved in ischemia-reperfusion-related apoptotic cell death. Furthermore, autophagic degradation of cellular compounds relieves intracellular adenosine triphosphate level for the energy depressed cells. Strategies targeting the mechanisms involved in energy metabolism, inflammatory response, and autophagy might be especially useful to prevent the increased risk for ischemia-reperfusion injury in aged livers after major hepatic surgery.

Outcome after liver transplantation in elderly recipients (>65 years) - A single-center retrospective analysis

BACKGROUND

Liver transplantation (LT) in elderly recipients is controversially discussed in the literature with only little data on long-term outcome available. We aimed to evaluate the safety and efficiency of LT in elderly recipients (>65 years).

METHODS

Between 1989-2016, 139 patients >65 years-old were listed for liver transplantation, and 76 (55%) were transplanted. Patient outcome and characteristics were evaluated separately for the time period before (1989-2004) and after (2005-2016) MELD-implementation. Post-transplant outcome was compared between the elderly cohort and LT-recipients aged 18-65 years (n = 1395).

RESULTS

Overall survival of patients >65 years was better in the MELD-era compared to the earlier period (1- and 5-year-survival: 73%, 60% vs. 69%, 37%, respectively; p = 0.055). The main differences between the two groups included higher recipient age (p = 0.001) and BMI (p = 0.001), higher donor age (p < 0.001), less need of intraoperative red blood cells (p = 0.008) and a lower number of postoperative rejections (p = 0.03) after 2004. Comparing the overall survival of patients transplanted in the MELD-era aged 18-65 years vs. >65 years displayed comparable 1- and 5 year-survival rates (81%, 68% vs. 73% and 60%, respectively, p = 0.558).

CONCLUSION

In the modern era, outcome of patients receiving LT with >65 years is comparable to <65 year-old patients. After careful evaluation, patients >65 years old should be considered for LT.

Ex situ machine perfusion as a tool to recondition steatotic donor livers: Troublesome features of fatty livers and the role of defatting therapies. A systematic review

Long-standing research has shown that increased lipid content in donor livers is associated with inferior graft outcomes posttransplant. The global epidemic that is obesity has increased the prevalence of steatosis in organ donors, to the extent that it has become one of the main reasons for declining livers for transplantation. Consequently, it is one of the major culprits behind the discrepancy between the number of donor livers offered for transplantation and those that go on to be transplanted. Steatotic livers are characterized by poor microcirculation, depleted energy stores because of an impaired capacity for mitochondrial recovery, and a propensity for an exaggerated inflammatory response following reperfusion injury culminating in poorer graft function postoperatively. Ex situ machine perfusion, currently a novel method in graft preservation, is showing great promise in providing a tool for the recovery and reconditioning of marginal livers. Hence, reconditioning these steatotic livers using machine perfusion has the potential to increase the number of liver transplants performed. In this review, we consider the problematic issues associated with fatty livers in the realm of transplantation and discuss pharmacological and nonpharmacological options that are being developed to enhance recovery of these organs using machine perfusion and defatting strategies.

Oil Red O Is a Useful Tool to Assess Donor Liver Steatosis on Frozen Sections During Transplantation

Oil Red O is a useful tool to assess donor liver steatosis on frozen sections during transplantation. Steatosis is a frequent finding in liver evaluation during transplantation, accounting for 9% to 26% of biopsied donor liver. The degree of macrovesicular steatosis is classified as mild, moderate, and severe; the latter is considered an absolute contraindication to liver transplantation because it is associated with poor allograft outcome. Because of the scarcity of organs, there is a debate whether livers with less severe macrovesicular steatosis are still suitable for transplant. Consequently, tools or methods that allow a more accurate intraoperative assessment of steatosis on frozen sections are mandatory. The aim of this study is to improve intraoperative evaluation of steatosis during transplantation using Oil Red O stain on liver biopsies.

METHODS

Twenty consecutive liver biopsies of donors were collected during transplantation procedures from September 2017 to February 2018 at the Institute of Pathology of the University and Hospital Trust of Verona, Italy. Each liver biopsy was cut at a different thickness (3, 5, and 8 μm) and stained with both Oil Red O and conventional hematoxylin and eosin for intraoperative consultation. The degree (percentage of hepatocytes involved) of fatty changes was recorded. The results obtained during the intraoperative consultation were finally compared with the formalin-fixed and paraffin-embedded permanent section.

RESULTS

Assessment of steatosis on hematoxylin and eosin frozen sections was reported as mild in 17 cases (85%), moderate in 2 cases (10%) and severe in 1 case (5%). Oil Red O frozen sections reported the following results: mild steatosis in 16 cases (80%), moderate in 2 cases (10%), and severe in 2 cases (10%). The percentage of liver steatosis obtained with Oil Red O was consistent in all cases with that of the permanent sections. The staining procedure for Oil Red O required approximately 18 minutes.

CONCLUSIONS

Oil Red O special stain is a fast and inexpensive tool to improve the assessment of steatosis on frozen biopsies during liver transplantation.

Allowable warm ischemic time and morphological and biochemical changes in uterine ischemia/reperfusion injury in cynomolgus macaque: a basic study for uterus transplantation

STUDY QUESTION

How long is the allowable warm ischemic time of the uterus and what morphological and biochemical changes are caused by uterine ischemia/reperfusion injury in cynomolgus macaques?

SUMMARY ANSWER

Warm ischemia in the uterus of cynomolgus macaques is tolerated for up to 4 h and reperfusion after uterine ischemia caused no further morphological and biochemical changes.

WHAT IS KNOWN ALREADY

Uterus transplantation is a potential option for women with uterine factor infertility. The allowable warm ischemic time and ischemia/reperfusion injury of the uterus in humans and non-human primates is unknown.

STUDY DESIGN, SIZE, DURATION

This experimental study included 18 female cynomolgus macaques with periodic menstruation.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Animals were divided into six groups of three monkeys each: a control group and groups with uterine ischemia for 0.5, 1, 2, 4 and 8 h. Biopsies of uterine tissues were performed before blood flow blockage, after each blockage time, and after reperfusion for 3 h. Blood sampling was performed after each blockage time, and after reperfusion for 5, 15 and 30 min for measurement of biochemical data. Resumption of menstruation was monitored after the surgical procedure. Morphological, physiological and biochemical changes after ischemia and reperfusion were evaluated.

MAIN RESULTS AND THE ROLE OF CHANCE

Mild muscle degeneration and zonal degeneration were observed in all animals subjected to warm ischemia for 4 or 8 h, but there were no marked differences in the appearance of specimens immediately after ischemia and after reperfusion for 3 h in animals subjected to 4 or 8 h of warm ischemia. There were no significant changes in any biochemical parameters at any time point in each group. Periodical menstruation resumed in all animals with warm ischemia up to 4 h, but did not recover in animals with warm ischemia for 8 h with atrophic uteri.

LIMITATIONS, REASON FOR CAUTION

Warm ischemia in actual transplantation was not exactly mimicked in this study because uteri were not perfused, cooled, transplanted or reanastomosed with vessels. Results in non-human primates cannot always be extrapolated to humans.

WIDER IMPLICATIONS OF THE FINDINGS

The findings suggest that the tolerable warm ischemia time in the uterus is expected to be longer than that in other vital organs.

STUDY FUNDING/COMPETING INTEREST(S)

This study was supported by the Japan Society for the Promotion of Science (JSPS) KAKENHI Grant Number 26713050. None of the authors has a conflict of interest to declare.

Liver Transplantation With Old Grafts: A Ten-Year Experience

BACKGROUND

The persistent scarcity of donors has prompted liver transplantation teams to find solutions for increasing graft availability. We report our experience of liver transplantations performed with grafts from older donors, specifically over 70 and 80 years old.

PATIENTS AND METHODS

We analyzed our prospectively maintained single-center database from January 1, 2005, to December 31, 2014, with 380 liver transplantations performed in 354 patients. Six groups were composed according to donor age: <40 (n = 84), 40 to 49 (n = 67), from 50 to 59 (n = 62), from 60 to 69 (n = 76), from 70 to 79 (n = 64), and ≥80 years (n = 27).

RESULTS

Donors <40 years of age had a lower body mass index, died more often from trauma, and more often had cardiac arrest and high transaminase levels. In contrast, older donors (≥70 years of age) died more often from stroke. Recipients of grafts from donors <50 years of age were more frequently infected by hepatitis C virus; recipients of oldest grafts more often had hepatocellular carcinoma. Cold ischemia time was the shortest in donors >80 years of age. Patient survival was not significantly different between the groups. In multivariate analysis, factors predicting graft loss were transaminase peak, retransplantation and cold ischemia time but not donor age.

CONCLUSIONS

Older donors >70 and >80 years of age could provide excellent liver grafts.

Hypothermic Machine Preservation of the Liver: State of the Art

PURPOSE OF REVIEW

In this review, we highlight which livers may benefit from additional treatment before implantation and describe the concept of hypothermic machine liver perfusion. Furthermore, we explain why cold oxygenated perfusion concepts could potentially lead to a breakthrough in this challenging field of transplantation. Accordingly, we summarize recent clinical applications of different hypothermic perfusion approaches.

RECENT FINDINGS

The impact of end-ischemic, hypothermic liver perfusion in liver transplantation is currently assessed by two multicenter, randomized controlled trials. Recently, new applications of hypothermic perfusion showed promising results and recipients were protected from severe intrahepatic biliary complications, despite the use of very extended criteria grafts including donation after circulatory death livers.

SUMMARY

Hypothermic machine liver perfusion is beneficial for high-risk livers and protects recipients from most feared complications. Importantly, such easy approach is currently implemented in several European centers and new markers obtained from perfusate may improve the prediction of liver function in the future.

Elderly donor graft for liver transplantation: Never too late

The definitive treatment for end stage liver disease remains a liver transplant and hence livers are needed for these patients along with cases of acute fulminant liver failure. Hence livers are a scarce and highly valuable commodity in the current time. By extending the pool of donors to include the elderly livers, it allows for increased availability of donors and reduces the mortality that is associated with the waiting list itself. There is an increasing prevalence of end stage liver disease due to conditions like chronic hepatitis B and C, non-alcoholic steatohepatitis, alcoholic liver disease. Many studies show non-inferior outcomes when elderly livers are used as a vigorous selection process is implemented. The process takes into account the characteristics of the donor, graft and recipient allowing for appropriate donor-recipient coupling. To meet the increasing demands of livers, elderly donors should be utilized for liver transplantation. The aim of this review article is to describe the aging process of the liver and the outcomes associated with use of elderly livers for transplantation.

Systematic review and meta-analysis of liver transplantation using grafts from deceased donors aged over 70 years

INTRODUCTION

Due to the current organ shortage, nearly 20% of patients die waiting for a liver transplant (LT). The average donor age is on the rise, and grafts from elderly donors are offered as extended criteria grafts.

METHODS

This is a meta-analysis comparing the outcome differences of adult patients undergoing LT using grafts from <70-year-old donors vs >70-year-old donors. The primary end-points were graft and patient survival. Secondary outcomes were biliary and vascular complications as well as graft function. The odds ratio (OR) is a summary statistic with the corresponding 95% confidence interval; P < .05 was considered to be statistically significant.

RESULTS

Eight nonrandomized comparative studies with 4376 LT recipients were included. About 79.9% and 20.1% of the grafts were from <70-year-old and >70-year-old donors, respectively. Graft survival at 1 year was similar between the two groups (P = .11), but there was better 3-year and 5-year graft survival in the >70-year-old group (P = .006 and P < .0001, respectively). Patient survival was also similar between the groups at 1 year (P = .54), but with better survival at 3-year and 5-year follow-ups (P = .007 and P < .0001, respectively) in the >70-year-old group. There were no statistically significant differences in the incidence of biliary, vascular, and graft functional-related complications.

CONCLUSION

Liver grafts from selected >70-year-old donors do not pose added organ-specific risks and thus have comparable transplantation outcomes.

Hypothermic machine perfusion with metformin-University of Wisconsin solution for ex vivo preservation of standard and marginal liver grafts in a rat model

AIM

To compare the effect of University of Wisconsin (UW) solution with or without metformin, an AMP-activated protein kinase (AMPK) activator, for preserving standard and marginal liver grafts of young and aged rats ex vivo by hypothermic machine perfusion (HMP).

METHODS

Eighteen young (4 mo old) and 18 aged (17 mo old) healthy male SD rats were selected and randomly divided into three groups: control group, UW solution perfusion group (UWP), and UW solution with metformin perfusion group (MUWP). Aspartate aminotransferase (AST), alanine aminotransferase (ALT), lactate dehydrogenase (LDH), interleukin-18 (IL-18), and tumor necrosis factor-alpha (TNF-α) in the perfused liquid were tested. The expression levels of AMPK and endothelial nitric oxide synthase (eNOS) in liver sinusoidal endothelial cells were also examined. Additionally, microscopic evaluation of the harvested perfused liver tissue samples was done.

RESULTS

AST, ALT, LDH, IL-18 and TNF-α levels in the young and aged liver-perfused liquid were, respectively, significantly lower in the MUWP group than in the UWP group (P < 0.05), but no significant differences were found between the young and aged MUWP groups. Metformin increased the expression of AMPK and eNOS protein levels, and promoted the extracellular release of nitric oxide through activation of the AMPK-eNOS mediated pathway. Histological examination revealed that in the MUWP group, the extent of liver cells and tissue damage was significantly reduced compared with the UWP group.

CONCLUSION

The addition of metformin to the UW preservative solution for ex vivo HMP can reduce rat liver injury during cold ischemia, with significant protective effects on livers, especially of aged rats.

A Donor Age-Based and Graft Volume-Based Analysis for Living Donor Liver Transplantation in Elderly Recipients

Background

Given the expected increase in the number of elderly recipients, details regarding how clinical factors influence the outcome in living donor liver transplantation (LDLT) for the elderly remain unclear. We examined the survival outcomes according to the results of donor age-based and graft volume–based analyses and assessed the impact of prognostic factors on the survival after LDLT for elderly recipients.

Methods

The 198 adult recipients were classified into 2 groups: an elderly group (n = 70, E group; ≥ 60 years of age) and a younger group (n = 128, Y group; <60 years of age). We analyzed the prognostic factors for the survival in the E group and the survival rate for both groups at several follow-up points and conducted subgroup analyses in the E group by combining the donor age (≥50 vs <50 years) and graft weight (GW)/standard liver volume (SLV) (≥40% vs <40%).

Results

Donor age (hazard ratio [HR], 2.17; P = 0.062) and GW/SLV (HR, 1.80; P = 0.23) tended to have a high HR in the E group. The overall patient survival rates at 1, 3, and 5 years were 78.3%, 73.0%, and 61.0% in the E group, and 82.0%, 75.1%, and 69.2% in the Y group, respectively (P = 0.459). However, the outcomes tended to be worse in recipients of grafts from donors ≥50 years of age than in those with grafts from younger donors with GW/SLV < 40% (P = 0.048).

Conclusions

A worse outcome might be associated with aging of the donor, which leads to impairment of the graft function and liver regeneration. Both the graft volume and donor age should be considered when choosing grafts for LDLT in elderly patients.

How Spain Reached 40 Deceased Organ Donors per Million Population

With 40 donors and more than 100 transplant procedures per million population in 2015, Spain holds a privileged position worldwide in providing transplant services to its patient population. The Spanish success derives from a specific organizational approach to ensure the systematic identification of opportunities for organ donation and their transition to actual donation and to promote public support for the donation of organs after death. The Spanish results are to be highlighted in the context of the dramatic decline in the incidence of brain death and the changes in end-of-life care practices in the country since the beginning of the century. This prompted the system to conceive the 40 donors per million population plan, with three specific objectives: (i) promoting the identification and early referral of possible organ donors from outside of the intensive care unit to consider elective non-therapeutic intensive care and incorporate the option of organ donation into end-of-life care; (ii) facilitating the use of organs from expanded criteria and non-standard risk donors; and (iii) developing the framework for the practice of donation after circulatory death. This article describes the actions undertaken and their impact on donation and transplantation activities.

Liver Transplantation With Older Donors: A Comparison With Younger Donors in a Context of Organ Shortage

BACKGROUND

Older liver grafts have been considered in the past decade due to organ shortage. The aim was to compare outcomes after liver transplantation with either younger or older donors.

METHODS

Patients transplanted in our center between 2004 and 2014 with younger donors (younger than 60 years; n = 253) were compared with older donors (older than 75 years; n = 157). Multiorgan transplantations, split grafts, or non-heart-beating donors were not included.

RESULTS

Donors in the older group were mostly women deceased from stroke, and only 3 patients had experienced cardiac arrest. Liver tests were significantly better in the older group than in the younger group. There was no difference regarding cold ischemia time, model for end-stage liver disease score, and steatosis. There was no significant difference regarding primary nonfunction and dysfunction, hepatic artery and biliary complications, and retransplantation rates. Graft survival was not different (65% and 64% in the older and younger groups, P = 0.692). Within the older group, hepatitis C infection, retransplantation, and emergency transplantation were associated with poor graft survival.

CONCLUSIONS

Provided normal liver tests and the absence of cardiac arrest in donors, older liver grafts (>75 years) may be safely attributed to non-hepatitis C-infected recipients in the setting of a first and nonurgent transplantation.

Octogenarian liver grafts: Is their use for transplant currently justified?

AIM

To analyse the impact of octogenarian donors in liver transplantation.

METHODS

We present a retrospective single-center study, performed between November 1996 and March 2015, that comprises a sample of 153 liver transplants. Recipients were divided into two groups according to liver donor age: recipients of donors ≤ 65 years (group A; n = 102), and recipients of donors ≥ 80 years (group B; n = 51). A comparative analysis between the groups was performed. Quantitative variables were expressed as mean values and SD, and qualitative variables as percentages. Differences in properties between qualitative variables were assessed by χ² test. Comparison of quantitative variables was made by t-test. Graft and patient survivals were estimated using the Kaplan-Meier method.

RESULTS

One, 3 and 5-year overall patient survival was 87.3%, 84% and 75.2%, respectively, in recipients of younger grafts vs 88.2%, 84.1% and 66.4%, respectively, in recipients of octogenarian grafts (P = 0.748). One, 3 and 5-year overall graft survival was 84.3%, 83.1% and 74.2%, respectively, in recipients of younger grafts vs 84.3%, 79.4% and 64.2%, respectively, in recipients of octogenarian grafts (P = 0.524). After excluding the patients with hepatitis C virus cirrhosis (16 in group A and 10 in group B), the 1, 3 and 5-year patient (P = 0.657) and graft (P = 0.419) survivals were practically the same in both groups. Multivariate Cox regression analysis demonstrated that overall patient survival was adversely affected by cerebrovascular donor death, hepatocarcinoma, and recipient preoperative bilirubin, and overall graft survival was adversely influenced by cerebrovascular donor death, and recipient preoperative bilirubin.

CONCLUSION

The standard criteria for utilization of octogenarian liver grafts are: normal gross appearance and consistency, normal or almost normal liver tests, hemodynamic stability with use of < 10 μg/kg per minute of vasopressors before procurement, intensive care unit stay < 3 d, CIT < 9 h, absence of atherosclerosis in the hepatic and gastroduodenal arteries, and no relevant histological alterations in the pre-transplant biopsy, such as fibrosis, hepatitis, cholestasis or macrosteatosis > 30%.

Liver Transplantation Using Donation After Brain and Cardiac Death: A Single-Center Experience in China

BACKGROUND

Liver transplantation (LTx) using donation after brain and cardiac death (DBCD) has increased steadily in China. The aims of this study were to evaluate the outcomes of DBCD LTx and to assess its feasibility to expand the donor pool.

METHODS

We retrospectively analyzed the clinical characteristics of DBCD donors and recipients, survival of allografts and recipients, and prognostic factors in DBCD LTx recipients from March 2010 to December 2014 in our institution.

RESULTS

DBCD LTx (n = 102) were performed in our institution during the research period, and the successful donation rate was 26.0%. Mean warm ischemia time and cold ischemia time were 14.39 minutes and 5.29 hours, respectively. The overall and biliary complication rates were 45.1% and 16.7%, respectively. Donor age (P = .043), intra-operative blood loss (P = .048), and operation time (P = .045) were significantly different between the complication and non-complication groups. The 1-, 2-, and 3-year survival rates of patients and grafts were 88.0%, 84.6%, 84.6%, and 85.7%, 78.6%, and 78.6%, respectively. The 1- and 2-year overall survival rates of hepatocellular carcinoma patients were 91.9% and 80.5%, respectively whereas the recurrence-free survival rates were 84.9% and 77.2%, respectively. The patient and graft survival rates were not statistically different between the <55-year and ≥55 year groups, but complication rate was higher in the older group than in the younger group (P = .003).

CONCLUSIONS

The outcome of DBCD LTx is favorable in our institution, with careful donor and recipient selection and careful peri-operative management. DBCD is an optimized solution for organ shortage in today's China.

The use of old donors in liver transplantation

The process of ageing has an impact on the entire human body including the organ systems. In transplantation, professionals are daily faced with risk assessment of suitable donor offers , whether to accept a liver graft for a specific recipient. In this context, livers from elderly donors are more frequently accepted for transplantation, to increase the donor pool and compensate the high waiting list mortality. In the current practice it is not unusual to accept 60-year old donor livers for transplantation, as the donor demographics have significantly changed over the years. However, controversy exists regarding the use of livers from donors above 70 or 80 years, particular in combination with other risk factors, e.g. liver steatosis, warm ischaemia or long cold storage. This review focuses first on the impact of ageing on liver morphology and function. Second, we will highlight outcome after transplantation from elderly donors. Finally, we describe further risk factors and donor-recipient selection under the scope of old donor organs and include our institutional experience and policy.

Hypo- and normothermic perfusion of the liver: Which way to go?

The demand of donor livers for transplantation exceeds the supply. In an attempt to maximize the number of potentially usable donor livers, several centers are exploring the role of machine perfusion. This review provides an update on machine perfusion strategies and basic concepts, based on current clinical issues, and discuss challenges, including currently used biomarkers for assessing the quality and viability of perfused organs. The potential benefits of machine perfusion on immunogenicity and the consequences on post-operative immunosuppression management are discussed.

Initial Poor Function and Primary Nonfunction in Deceased-Donor Orthotopic Liver Transplantation Maintaining Short Cold Ischemic Time

BACKGROUND

Nations with emerging deceased-donor liver transplantation programs, such as India, face problems associated with poor donor maintenance. Cold ischemic time (CIT) is typically maintained short by matching donor organ recovery and recipient hepatectomy to achieve maximum favorable outcome. We analyzed different extended criteria donor factors including donor acidosis, which may act as a surrogate marker of poor donor maintenance, to quantify the risk of primary nonfunction (PNF) or initial poor function (IPF).

METHODS

A single-center retrospective outcome analysis of prospectively collected data of patients undergoing deceased-donor liver transplantation over 2 years to determine the impact of different extended criteria donor factors on IPF and PNF.

RESULTS

From March 2013 to February 2015, a total of 84 patients underwent deceased-donor liver transplantation. None developed PNF. Thirteen (15.5%) patients developed IPF. Graft macrosteatosis and donor acidosis were only related to IPF ( P = .002 and P = .032, respectively). Cold ischemic time was maintained short (81 cases ≤8 hours, maximum 11 hours) in all cases.

CONCLUSION

Poor donor maintenance as evidenced by donor acidosis and graft macrosteatosis had significant impact in developing IPF when CIT is kept short. Similar study with larger sample size is required to establish extended criteria cutoff values.