A national mandatory-split liver policy: A report from the Italian experience

Efficiency of machine perfusion in pediatric liver transplantation

Liver transplantation is the only life-saving procedure for children with end-stage liver disease. The field is however heterogenic with various graft types, recipient age, weight, and underlying diseases. Despite recently improved overall outcomes and the expanded use of living donors, waiting list mortality remains unacceptable, particularly in small children and infants. Based on the known negative effects of elevated donor age, higher body mass index, and prolonged cold ischemia time, the number of available donors for pediatric recipients is limited. Machine perfusion has regained significant interest in the adult liver transplant population during the last decade. Ten randomized controlled trials are published with an overall advantage of machine perfusion techniques over cold storage regarding postoperative outcomes, including graft survival. The concept of hypothermic oxygenated perfusion (HOPE) was the first and only perfusion technique used for pediatric liver transplantation today. In 2018 the first pediatric candidate received a full-size graft donated after circulatory death with cold storage and HOPE, followed by a few split liver transplants after HOPE with an overall limited case number until today. One series of split procedures during HOPE was recently presented by colleagues from France with excellent results, reduced complications, and better graft survival. Such early experience paves the way for more systematic use of machine perfusion techniques for different graft types for pediatric recipients. Clinical reports of pediatric liver transplants with other perfusion techniques are awaited. Strong collaborative efforts are needed to explore the effect of perfusion techniques in this vulnerable population impacting not only the immediate posttransplant outcome but the development and success of an entire life.

Primary Liver Transplant in Biliary Atresia: The Case for and Against

The role of liver transplantation as a primary procedure in biliary atresia has been argued over for at least 40 years, indeed since the coming of age of safe liver transplantation during the 1980s. Yet, it is not a common option in most series (usually ≤5%) and typically reserved for those with late presentations (arguably >100 days) with established cirrhosis. This review presents the pros and cons of primary liver transplant. The pros are based upon the observation that at best a Kasai portoenterostomy (KPE) is simply palliative in most, and at worse has no effect whatsoever on restoration of bile flow and is therefore pointless. Set against this are the cons: there is a dearth of prognostic tests (clinical, biochemical, or histological) at the time of presentation which may predict inevitable failure; the possibility of long-term native liver survival to adulthood in a proportion (albeit a minority); and the implied increased need for donor organs suitable for infants - a stressor for an already overstressed system. Improving results from KPE in terms of increasing the proportions clearing their jaundice and minimizing the effects of chronic liver fibrosis and cirrhosis would surely limit the siren calls for primary transplants but the key must be better discrimination at presentation with the use of biomarkers (circulatory or histological, individually or together) to enable better decision making.

Tailoring allocation policies and improving access to paediatric liver transplantation over a 16-year period

BACKGROUND & AIMS

Mortality on the paediatric liver transplantation (pLT) waiting list (WL) is still an issue. We analysed the Italian pLT WL to evaluate the intention-to-treat (ITT) success rate and to identify factors influencing success.

METHODS

All children (<18 years) listed for pLT in Italy between 2002-2018 were included (Era 1 [2002-2007]: centre-based allocation; Era 2 [2008-2014]: national allocation; Era 3 [2015-2018]: national allocation+mandatory-split policy).

RESULTS

A total of 1,424 patients (median age: 2.0 [IQR 1.0-9.0] years; median weight: 12.0 kg [IQR 7-27]) were listed for pLT. Median WL time was 2 days (IQR 1-5) for Status 1 and 44 days (IQR 15-120) for non-Status 1 patients; 1,302 children (91.4%) were transplanted (67.3% with split grafts), while 50 children (3.5%) dropped off the WL (2.5% death, 1.0% clinical deterioration). Predictive factors for receiving LT included Status 1 (hazard ratio [HR] 1.66, p = 0.001), Status 1B (HR 1.96, p = 0.016), Status 2A (HR 2.15, p = 0.024) and each 1-point increase in PELD/MELD score. Children with recipient's weight >25 kg, blood group O or awaiting pLT combined with other organs had less chance of being transplanted. ITT patient survival rates were 90.5% at 1 year and 87.5% at 5 years, remaining stable across eras. Risk factors for ITT survival were re-transplantation (HR 5.83, p <0.001), Status 1 (HR 2.28, p = 0.006), Status 1B (HR 2.90, p = 0.014), Status 2A (HR 9.12, p <0.001), recipient weight <6 kg (HR 4.53, p <0.001) and low-volume activity (HR 4.38, p = 0.001).

CONCLUSIONS

In Italy, continuous adaption of paediatric organ allocation policies via the introduction of national allocation, paediatric prioritisation rules and a mandatory-split policy have helped maximise the use of donors for paediatric candidates and to minimise WL mortality without compromising outcomes.

IMPACT AND IMPLICATIONS

Globally, paediatric liver transplant candidates still suffer from high mortality. Over recent decades, the continuous adaption of organ allocation policies in Italy has led to excellent outcomes for children awaiting liver transplantation. The mortality rate of paediatric liver transplant candidates has been minimised to almost zero, mainly using grafts from deceased donors. Paediatric prioritisation rules, national organ exchange organisation and a mandatory-split liver policy have resulted in a unique allocation model for paediatric liver transplant candidates and represent a landmark for the paediatric transplant community.

Technical Variant Liver Transplant Utilization for Pediatric Recipients: Equal Graft Survival to Whole Liver Transplants and Promotion of Timely Transplantation Only When Performed at High-volume Centers

BACKGROUND

Technical variant liver transplantation (TVLT) is a strategy to mitigate persistent pediatric waitlist mortality in the United States, although its implementation remains stagnant. This study investigated the relationship between TVLT utilization, transplant center volume, and graft survival.

METHODS

Pediatric liver transplant recipients from 2010 to 2020 (n = 5208) were analyzed using the Scientific Registry of Transplant Recipients database. Transplant centers were categorized according to the average number of pediatric liver transplants performed per year (high-volume, ≥5; low-volume, <5). Graft survival rates were compared using Kaplan-Meier curves and log-rank tests. Cox proportional hazards models were used to identify predictors of graft failure.

RESULTS

High-volume centers demonstrated equivalent whole liver transplant and TVLT graft survival ( P = 0.057) and significantly improved TVLT graft survival compared with low-volume centers ( P < 0.001). Transplantation at a low-volume center was significantly associated with graft failure (adjusted hazard ratio, 1.6; 95% confidence interval, 1.14-2.24; P = 0.007 in patients <12 y old and 1.8; 95% confidence interval, 1.13-2.87; P = 0.013 in patients ≥12 y old). A subset of high-volume centers with a significantly higher rate of TVLT use demonstrated a 23% reduction in waitlist mortality.

CONCLUSIONS

Prompt transplantation with increased TVLT utilization at high-volume centers may reduce pediatric waitlist mortality without compromising graft survival.

Revisiting the forgotten "full-right full-left" liver division: Simplified technique and new strategical considerations for clinical implementation in Italy

BACKGROUND

Full-right/full-left liver splitting was introduced early in the 90s as part of the great wave of technical innovations that characterized that decade. One approach was to divide the liver on the right of the Cantlie's line and leave the middle hepatic vein with the left graft, with both grafts allocated to adults. Both grafts had some functional disadvantages and exposed the adult recipients to some early hepatic dysfunction, and the results were not great. An alternative approach consisted of an ex situ division of the liver, exactly along Cantlie's line, thus sharing the middle hepatic vein between the two grafts. None of these two techniques were really adopted, and there has been nearly no transplantation of this type in the last decade worldwide.

METHOD AND RESULTS

The authors propose a variation of the latter technique that was used recently with success: The division of the liver is made simpler; the two grafts are prepared ex situ and need a simple vascular reconstruction (one venous patch on each graft); and the grafts can be implanted using very standard techniques.

CONCLUSION

Because candidates for liver transplantation weighing 25-60 kg (old children, teenagers, and some small adults) are often at some disadvantage in getting size-matched livers (this range of weight is less represented in the donor population), implementing the latter technique would help provide adequate grafts for them. In Italy, where many livers offered for splitting are not used, there would be ample room for implementing this option within the actual donor pool and allocation system.

Combining living and deceased donation for pediatric first isolated liver transplantation: A win-win even in countries with high deceased donor donation rates

BACKGROUND

Split and living donor liver transplantations are both key surgical strategies for development of pediatric liver transplant programs. Often, however, teams tend to prioritize only one preferentially.

METHODS

In the context of a very active national split liver graft allocation program (Italy), retrospective study of 226 consecutive pediatric first isolated liver transplants performed by a single team using organs from both deceased and living donors. Clinical characterisitics and outcome were compared.

RESULTS

In the context of a steadily slowly decreasing split graft offer, living donation activity steadily increased. Deceased and living donation accounted for 52.6% and 47.4% of transplantations, respectively. Both strategies were equally used for transplanting patients up to 30 kg of weight, while deceased donors were predominantly used for older recipients. Technical variants represented 86% of all transplants, with 183 conisting of left lateral segment grafts (76 split liver grafts and 107 left grafts from living donors). Outcome of both surgical strategies was similar, with excellent outcomes at early, mid-, and long-term.

CONCLUSIONS

Splitting livers of deceased donors and using living donation were complementary and non-competitive strategies for developping pediatric liver transplant activity. Implementing both activities in parallell allowed to maintain stable the number of annual transplant in Italy and allowed to reach superior outcomes. This analysis provides evidence that living donation plays a role in Italy despite an existing very active "mandatory-split" national policy.

Simultaneous split liver/kidney transplantation: A national and single center experience report

BACKGROUND

End-stage liver disease (ESLD) and end-stage renal disease (ESRD) are prevalent diseases for which the definitive treatment is transplantation. With limited organ supply, strategies to maximize organ availability has led to increasing rates of split liver transplantations for ESLD patients. Therefore, simultaneous split liver and kidney transplantations (SSLK) for patients with ESLD and ESRD could represent a treatment option for comorbid patients. However, current practice and outcomes after SSLK are unknown.

METHODS

We aim to report national trends and our experience with patients undergoing SSLK. We performed a retrospective review of the United Network for Organ Sharing (UNOS) Standard Transplant Analysis and Research file from January 2011-April 2022. Descriptive analysis of preoperative characteristics, postoperative outcomes and actuarial graft and patient survivals are reported.

RESULTS

National review of the UNOS transplant registry from 2011-2021 of adult patients undergoing initial transplantation via SSLK demonstrates that this procedure remains uncommon, with only 76 such cases captured in that time. Nevertheless, survival rates at 1, 3, and 5 years remains robust, at 94%, 92%, and 90% for patients overall, 90%, 88%, 88%, for the liver graft, and 93%, 91%, 88% for the kidney graft, respectively. Review of a single center experience with three such patients from 2019-2021 has shown a safe, enduring transplant option with no graft complications seen.

CONCLUSIONS

SSLK is both safe and a feasible option to optimize organ supply while allowing recipients to receive quality liver and kidney grafts and should be considered more often by transplant centers going forward.

Improving outcomes of in situ split liver transplantation in Italy over the last 25 years

BACKGROUND & AIMS

Split liver transplant(ation) (SLT) is still considered a challenging procedure that is by no means widely accepted. We aimed to present data on 25-year trends in SLT in Italy, and to investigate if, and to what extent, outcomes have improved nationwide during this time.

METHODS

The study included all consecutive SLTs performed from May 1993 to December 2019, divided into three consecutive periods: 1993-2005, 2006-2014, and 2015-2019, which match changes in national allocation policies. Primary outcomes were patient and graft survival, and the relative impact of each study period.

RESULTS

SLT accounted for 8.9% of all liver transplants performed in Italy. A total of 1,715 in situ split liver grafts were included in the analysis: 868 left lateral segments (LLSs) and 847 extended right grafts (ERGs). A significant improvement in patient and graft survival (p <0.001) was observed with ERGs over the three periods. Predictors of graft survival were cold ischaemia time (CIT) <6 h (p = 0.009), UNOS status 2b (p <0.001), UNOS status 3 (p = 0.009), and transplant centre volumes: 25-50 cases vs. <25 cases (p = 0.003). Patient survival was significantly higher with LLS grafts in period 2 vs. period 1 (p = 0.008). No significant improvement in graft survival was seen over the three periods, where predictors of graft survival were CIT <6 h (p = 0.007), CIT <6 h vs. ≥10 h (p = 0.019), UNOS status 2b (p = 0.038), and UNOS status 3 (p = 0.009). Retransplantation was a risk factor in split liver graft recipients, with significantly worse graft and patient survival for both types of graft (p <0.001).

CONCLUSIONS

Our analysis showed Italian SLT outcomes to have improved over the last 25 years. These results could help to dispel reservations regarding the use of this procedure.

IMPACT AND IMPLICATIONS

Split liver transplant(ation) (SLT) is still considered a challenging procedure and is by no means widely accepted. This study included all consecutive in situ SLTs performed in Italy from May 1993 to December 2019. With more than 1,700 cases, it is one of the largest series, examining long-term national trends in in situ SLT since its introduction. The data presented indicate that the outcomes of SLT improved during this 25-year period. Improvements are probably due to better recipient selection, refinements in surgical technique, conservative graft-to-recipient matching, and the continuous, yet carefully managed, expansion of donor selection criteria under a strict mandatory split liver allocation policy. These results could help to dispel reservations regarding the use of this procedure.

Utilization of Segmental Grafts Is Associated With Higher Transplant Rates in Pediatric Patients

INTRODUCTION

In July 2017, a policy to increase the use of segmental grafts (SGs) was implemented at our institution. The aim was to compare changes in waitlist activity after implementation of this policy.

METHODS

A single-center, retrospective study. Pediatric patients on the liver waiting list between January 2015 and December 2019 were screened. Patients were classified as receiving a liver transplant (LT) before (Period 1) or after (Period 2) policy changes. Primary end points were transplant rates and time to transplant.

RESULTS

Sixty five first LT performed on 65 patients were included. Twenty nine LT were performed during Period 1 and 36 during Period 2. More than half (55%) of LT in Period 2 were SG, compared to 10.3% in Period 1 (P < 0.001). Forty nine and 56 pediatric candidates on the waiting list accounted for 38.78 and 24.48 person-years during Period 1 and Period 2, respectively. Transplant rates per 100 person-years on the waiting list increased from 85.09 during Period 1 to 187.87 in Period 2 (Rate ratio: 2.20; P < 0.001). Median time to receive a LT decreased from 229 d in Period 1 to 75 d during Period 2 (P = 0.013). One-year patient survival rates were 96.6% in Period 1 and 95.7% in Period 2. One-year graft survival rates were 89.7% and 88% in Period 1 and Period 2, respectively.

CONCLUSIONS

A policy to increase the use of SG was associated with significantly higher transplant rates and lower waiting times. Implementation of this policy can be done successfully with no observed negative impact on patient and graft survival.

Split or whole liver transplantation? Utilization and posttransplant survival

BACKGROUND

Split liver transplantation (SLT), where a single donor liver is divided for transplantation to 2 recipients, has the potential to increase the availability of size-matched livers for pediatric candidates and expand the supply of donor organs available for adult candidates. Although SLT is a well-established technique, the number of SLTs has remained flat during the past 2 decades, partly due to concerns about the posttransplant survival of SLT recipients compared with whole liver transplantation (WLT) recipients. Prior work on SLT versus WLT survival analysis had limitations because, for pediatric recipients, it did not consider the correlations between donor age/weight and the allograft type, and for adult recipients, it may have included records where the donor livers did not meet the split liver criteria (splittable).

METHODS

Using the Organ Procurement and Transplantation Network's database (2003-2019), this study analyzes and compares (i) key characteristics of donors and recipients, (ii) donor-recipient match dynamics (organ offers and accept/decline decisions), and (iii) recipient posttransplant survival, for SLT and WLT.

RESULTS AND CONCLUSIONS

The results in this study show that the posttransplant survival of SLT and WLT recipients is similar (controlling for other confounding factors that may impact posttransplant survival), highlighting the importance of SLT for increasing the liver supply and potential benefits for both pediatric and adult candidates.

Long-term outcomes and health-related quality of life 20 years after pediatric liver transplantation

Pediatric liver transplantation is a challenging surgical procedure requiring complex post-transplant patient management. Liver transplantation in children should ensure long-term survival and good health-related quality of life (HR-QOL), but data in the literature are conflicting. With the aim of investigating survival and psychosocial outcomes of patients transplanted during childhood, we identified 40 patients with ≥ 20-year follow-up after liver transplantation regularly followed up at our Institution. Clinical charts were reviewed to retrieve patients' data. Psychosocial aspects and HR-QOL were investigated by an in-person or telephonic interview and by administering the WHOQOL-BREF questionnaire through an online form. Ten- and 20-year patient survival was 97.5% (95% CI 92.8-100%), whereas 10- and 20-year graft survival was 77.5% (65.6-91.6%) and 74.8% (62.5-89.6%), respectively. At last follow-up visit, 31 patients (77.5%) were receiving a tacrolimus-based immunosuppression. Twelve (32.4%) patients obtained a university diploma or higher, whereas 19 (51.4%) successfully completed high school. 81.1% of patients were active workers or in education, 17.5% had children, and 35% regularly practiced sport. 25 patients answered to the WHOQOL-BREF questionnaire. More than 60% of respondents did not report any disability and the perceived physical status was invariably good or very good. Median scores for physical health, psychological health, social relationships, and environment were 16.6, 14.7, 16, and 15, respectively. Pediatric liver transplantation is associated with excellent long-term survival and good HR-QOL. Psychological health and environment represent areas in which support would be needed to further improve HR-QOL.

Venous outflow obstruction in pediatric left lateral segment split liver transplantation

BACKGROUND

Venous outflow obstruction (VOO) is a known cause of graft and patient loss after pediatric liver transplantation (LT). We analyzed the incidence, risk factors, diagnosis, management, and outcome of VOO in a large, consecutive series of left lateral segment (LLS) split LT with end-to-side triangular venous anastomosis.

METHODS

We evaluated data collected in our prospective databases relative to all consecutive pediatric liver transplants performed from January 2006 to December 2021. We included in this study children undergoing LLS split liver transplant with end-to-side triangular anastomosis. Diagnosis of VOO was based on clinical suspicion and radiological confirmation.

RESULTS

VOO occurred in 24/279 transplants (8.6%), and it was associated with lower graft weight (p = .04), re-transplantation (p = .008), and presence of two hepatic veins (p < .0001). In presence of two segmental veins' orifices, the type of reconstruction (single anastomosis after venoplasty or double anastomosis) was not significantly related to VOO (p = .87). Multivariable analysis indicated VOO as a risk factor for graft lost (hazard ratio 3.21, 95% confidence interval 1.22-8.46; p = .01). Percutaneous Transluminal Angioplasty (PTA) was effective in 17/22 (77%) transplants. Surgical anastomosis was redone in one case. Overall six grafts (25%) were lost.

CONCLUSION

VOO after LLS split LT with end-to-side triangular anastomosis is an unusual but critical complication leading to graft loss in a quarter of cases. The occurrence of VOO was associated with lower graft weight, re-transplantation, and presence of two hepatic veins. PTA was safe and effective to restore proper venous outflow in most cases.

How to Structure a Successful Organ Donation and Transplantation System in Eight (Not So Easy) Steps: An Italian Case Study

Valuable information can be obtained from a systematic evaluation of a successful national transplant program. This paper provides an overview of Italy's solid organ transplantation program which is coordinated by the National Transplant Network (Rete Nazionale Trapianti) and The National Transplant Center (Centro Nazionale Trapianti). The analysis is based on a system-level conceptual framework and identifies components of the Italian system that have contributed to improving rates of organ donation and transplantation. A narrative literature review was conducted and the findings were validated iteratively with input from subject matter experts. The results were organized into eight critical steps, including 1) generating legal definitions of living and deceased donation, 2) taking steps to ensure that altruistic donation and transplantation become part of the national culture and a point of pride, 3) seeking out existing examples of successful programs, 4) creating a situation in which it is easy to become a donor, 5) learning from mistakes, 6) working to diminish risk factors that lead to the need for organ donation, 7) increasing the rate of donations and transplantations via innovative strategies and policies, and 8) planning for a system that supports growth.

Waitlist mortality of young patients with biliary atresia: Impact of allocation policy and living donor liver transplantation

Patients with biliary atresia (BA) below 2 years of age in need of a transplantation largely rely on partial grafts from deceased donors (deceased donor liver transplantation [DDLT]) or living donors (living donor liver transplantation [LDLT]). Because of high waitlist mortality in especially young patients with BA, the Eurotransplant Liver Intestine Advisory Committee (ELIAC) has further prioritized patients with BA listed before their second birthday for allocation of a deceased donor liver since 2014. We evaluated whether this Eurotransplant (ET) allocation prioritization changed the waitlist mortality of young patients with BA. We used a pre-post cohort study design with the implementation of the new allocation rule between the two periods. Participants were patients with BA younger than 2 years who were listed for liver transplantation in the ET database between 2001 and 2018. Competing risk analyses were performed to assess waitlist mortality in the first 2 years after listing. We analyzed a total of 1055 patients with BA, of which 882 had been listed in the preimplementation phase (PRE) and 173 in the postimplementation phase (POST). Waitlist mortality decreased from 6.7% in PRE to 2.3% in POST ( p = 0.03). Interestingly, the proportion of young patients with BA undergoing DDLT decreased from 32% to 18% after ET allocation prioritization ( p = 0.001), whereas LDLT increased from 55% to 74% ( p = 0.001). The proportional increase in LDLT decreased the median waitlist duration of transplanted patients from 1.5 months in PRE to 0.85 months in POST ( p = 0.003). Since 2014, waitlist mortality in young patients with BA has strongly decreased in the ET region. Rather than associated with prioritized allocation of deceased donor organs, the decreased waitlist mortality was related to a higher proportion of patients undergoing LDLT.

State of pediatric liver transplantation in the United States and achieving zero wait list mortality with ideal outcomes: A statement from the Starzl Network for Excellence in Pediatric Transplant Surgeon's Working Group

BACKGROUND

Liver transplant is a life-saving therapy that can restore quality life for several pediatric liver diseases. However, it is not available to all children who need one. Expertise in medical and surgical management is heterogeneous, and allocation policies are not optimally serving children. Technical variant grafts from both living and deceased donors are underutilized.

METHODS

Several national efforts in pediatric liver transplant to improve access to and outcomes from liver transplant for children have been instituted and include adjustments to allocation policies, UNOS-sponsored collaborative improvement projects, and the emergence of national learning networks to study ongoing challenges in the field the Surgical Working group of the Starzl Network for Excellence in Pediatric Transplantation (SNEPT) discusses key issues and proposes potential solutions to eliminate the persistent wait list mortality that pediatric patients face.

RESULTS

A discussion of the factors impacting pediatric patients' access to liver transplant is undertaken, along with a proposal of several measures to ensure equitable access to life-saving liver transplant.

CONCLUSIONS

Pediatric liver transplant wait list mortality can and should be eliminated. Several measures, including collaborative efforts among centers, could be leveraged to acheive this goal.

An appraisal of technical variant grafts compared to whole liver grafts in pediatric liver transplant recipients: Multicenter analysis from the SPLIT registry

BACKGROUND

Shortages of liver allografts for children awaiting transplantation have led to high LT waitlist mortality. Prior studies have shown that usage of TVG can reduce waiting time and waitlist mortality, but their use is not universal. We sought to compare patient and graft survival between WLG and TVG and to identify potential associated risk factors in a contemporary pediatric LT cohort.

METHODS

We performed a retrospective analysis of patient survival, graft survival, and biliary and vascular complications for LT recipients <18 years old entered into the Society of Pediatric Liver Transplantation prospective multicenter database.

RESULTS

Of 1839 LT recipients, 1029 received a WLG and 810 received a TVG from either a LD or a DD. There was no difference in patient survival or graft survival by graft type. Three-year patient survival and graft survival were 96%, 93%, and 96%, and 95%, 89%, and 92% for TVG-LD, TVG-DD, and WLG, respectively. Biliary complications were more frequent in TVG. Hepatic artery thrombosis was more frequent in WLG. Multivariate analysis revealed primary diagnosis was the only significant predictor of patient survival. Predictors for graft survival included time-dependent development of biliary and vascular complications.

CONCLUSIONS

There were no significant differences in patient and graft survival based on graft types in this North American multi-center pediatric cohort. Widespread routine use of TVG should be strongly encouraged to decrease mortality on the waitlist for pediatric LT candidates.

Impact of donor age on short-term outcomes after pediatric split liver transplantation

Background

Donor shortage is an important limitation of liver transplantation (LT). Split liver transplantation (SLT) may increase the sources of donors and reduce the problem of organ shortage. However, there are no standard criteria of the selection of SLT donor, especially regarding the donor age.

Methods

We retrospectively analyzed the clinical data of children who received initial SLT between January 2015 and December 2021. Based on the age of donors, the patients were divided into groups A (1-10 years old; n = 26), B (10-45 years old; n = 87), and C (45-55 years old; n = 27). The short-term (<1 year after SLT) outcomes of the recipients were analyzed.

Results

A total of 140 patients received SLT from 122 donors. The 1-, 3- and 12-month patient survival rates in group A were 100.0%, and the graft survival rates were 92.3%. The 1-, 3- and 12-month survival rates of patient and graft in group B were 97.7%, 96.6%, and 95.0%, respectively, and in group C were 85.2%, 85.2%, and 81.1%, respectively. The patient survival rate was significantly lower in group C than in groups A and B (p = 0.0082). There was no significant difference in graft survival between the three groups (p = 0.0545).

Conclusions

Similar results were obtained for pediatric SLT with donors <10 years old and 10-45 years old. Pediatric SLT can be performed with older donors (45-55 years) after strict donor selection and selection of appropriate recipients.

Increased use of split liver grafts in adult recipients following implementation of a pediatric liver transplant program

BACKGROUND

Split liver transplantation (SLT) is a strategy to address organ shortage, but is a technically more demanding procedure than whole graft liver transplantation (LT). We aimed to determine the outcomes following SLT in adult recipients as well as to highlight the impact that having a pediatric LT program has on SLT implementation.

METHODS

All SLTs conducted at a single-center from 2010 to 2019 were identified. Patient data was obtained through retrospective review of the electronic medical record. Kaplan-Meier analysis assessed primary outcomes of 1-,3-, and 5-year graft and patient survival.

RESULTS

We identified 37 SLTs performed at our institution from 2010 to 2019. Twenty-four donated livers resulted in 21 extended right lobes and 16 left lateral segments for adults and pediatrics recipients, respectively. Eighty-one percent (30/37) of the SLTs were performed after introduction of the combined pediatric program in 2016. 13/24 donor livers were split with both grafts allocated and used at our institution and 92% occurred after introduction of the pediatric program. Graft survival rates at 1-, 3-, and 5-years were 94% in adult recipients and 100% for all time periods in pediatric recipients. Actuarial post-transplant patient survival was 100% at 1-, 3-, and 5-years in both.

CONCLUSIONS

The introduction of a pediatric liver transplantation program resulted in more than a fourfold increase in the number of SLTs performed at our center. Increase in allocation and use of both grafts at our institution was also seen.

The role of liver transplantation in the care of primary hepatic vascular tumours in children

Liver transplantation (LT) is the standard of care for many liver conditions, such as end-stage liver diseases, inherited metabolic disorders, and primary liver malignancies. In the latter group, indications of LT for hepatoblastoma and hepatocellular carcinoma evolved and are currently available for many non-resectable cases. However, selection criteria apply, as the absence of active metastases. Evidence of good long-term outcomes has validated the LT approach for managing these malignancies in the context of specialist and multidisciplinary approach. Nevertheless, LT's role in treating primary vascular tumours of the liver in children, both benign and malignant, remains somewhat controversial. The rarity of the different diseases and the heterogeneity of pathological definitions contribute to the controversy and make evaluating the benefit/risk ratio and outcomes quite difficult. In this narrative review, we give an overview of primary vascular tumours of the liver in children, the possible indications and the outcomes of LT.

Machine Perfusion for Extended Criteria Donor Livers: What Challenges Remain?

Based on the renaissance of dynamic preservation techniques, extended criteria donor (ECD) livers reclaimed a valuable eligibility in the transplantable organ pool. Being more vulnerable to ischemia, ECD livers carry an increased risk of early allograft dysfunction, primary non-function and biliary complications and, hence, unveiled the limitations of static cold storage (SCS). There is growing evidence that dynamic preservation techniques—dissimilar to SCS—mitigate reperfusion injury by reconditioning organs prior transplantation and therefore represent a useful platform to assess viability. Yet, a debate is ongoing about the advantages and disadvantages of different perfusion strategies and their best possible applications for specific categories of marginal livers, including organs from donors after circulatory death (DCD) and brain death (DBD) with extended criteria, split livers and steatotic grafts. This review critically discusses the current clinical spectrum of livers from ECD donors together with the various challenges and posttransplant outcomes in the context of standard cold storage preservation. Based on this, the potential role of machine perfusion techniques is highlighted next. Finally, future perspectives focusing on how to achieve higher utilization rates of the available donor pool are highlighted.

Outcome of Extended Right Lobe Liver Transplantations

Split-liver transplantation offers a solution to the organ shortage problem. However, the outcomes of extended right lobe liver transplantation (ERLT) and whether it is a suitable alternative to full-size liver transplantation (FSLT) remain controversial. We compared the outcomes of ERLT and FSLT in adult recipients of 43,409 first deceased donor liver transplantations using Cox regression. We also analyzed 612 ERLT and 1224 FSLT 1:2 matched cases to identify factors that affect ERLT outcome. The risk of graft loss was significantly higher following ERLT than following FSLT during the first posttransplantation year in the matched and unmatched collective (hazard ratio [HR], 1.39 and 1.27 and P = 0.01 and 0.006, respectively). Every additional hour of cold ischemia time (CIT) increased the risk of 1-year graft loss by 10% in the ERLT group compared with only 3% in the FSLT group (P = 0.003 and <0.001, respectively). Importantly, the outcome of ERLT and FSLT did not differ significantly if the CIT was below 10 hours (HR, 0.71; P = 0.22). One-year graft and patient survival were lower in high-risk ERLT recipients with a Model for End-Stage Liver Disease (MELD) score of ≥20 (HR, 1.88; P = 0.03 and HR, 2.03; P = 0.02). In the male recipient-male donor combination, ERLT recipients had a higher risk of 1-year graft loss than FSLT recipients (HR, 2.44; P = 0.006). This was probably because of the significantly higher MELD score in ERLT recipients (P = 0.004). ERLT in adults is an adequate alternative to FSLT and offers an elegant solution to the problem of organ shortage as long as the cold storage is less than 10 hours and the recipient's MELD score is <20.

Variability of Care and Access to Transplantation for Children with Biliary Atresia Who Need a Liver Replacement

Background & Aims: Biliary atresia (BA) is the commonest single etiology indication for liver replacement in children. As timely access to liver transplantation (LT) remains challenging for small BA children (with prolonged waiting time being associated with clinical deterioration leading to both preventable pre- and post-transplant morbidity and mortality), the care pathway of BA children in need of LT was analyzed—from diagnosis to LT—with particular attention to referral patterns, timing of referral, waiting list dynamics and need for medical assistance before LT. Methods: International multicentric retrospective study. Intent-to-transplant study analyzing BA children who had indication for LT early in life (aged < 3 years at the time of assessment), over the last 5 years (2016−2020). Clinical and laboratory data of 219 BA children were collected from 8 transplant centers (6 in Europe and 2 in USA). Results: 39 patients underwent primary transplants. Children who underwent Kasai in a specialist -but not transplant- center were older at time of referral and at transplant. At assessment for LT, the vast majority of children already were experiencing complication of cirrhosis, and the majority of children needed medical assistance (nutritional support, hospitalization, transfusion of albumin or blood) while waiting for transplantation. Severe worsening of the clinical condition led to the need for requesting a priority status (i.e., Peld Score exception or similar) for timely graft allocation for 76 children, overall (35%). Conclusions: As LT currently results in BA patient survival exceeding 95% in many expert LT centers, the paradigm for BA management optimization and survival have currently shifted to the pre-LT management. The creation of networks dedicated to the timely referral to a pediatric transplant center and possibly centralization of care should be considered, in combination with implementing all different graft type surgeries in specialist centers (including split and living donor LTs) to achieve timely LT in this vulnerable population.

Graft weight integration in the early allograft dysfunction formula improves the prediction of early graft loss after liver transplantation

The role of the graft-to-recipient weight ratio (GRWR) in adult liver transplantation (LT) has been poorly investigated so far. The aim is to evaluate the contribution of the GRWR to the well-recognized early allograft dysfunction (EAD) model (i.e., Olthoff model) for the prediction of 90-day graft loss after LT in adults. Three hundred thirty-one consecutive adult patients undergoing LT between 2009 and 2018 at Tor Vergata and Sapienza University in Rome, Italy, served as the Training-Set. The Validation-Set included 123 LTs performed at the Erasmus Medical Center, Rotterdam, the Netherlands. The mEAD model for 90-day graft loss included the following variables: GRWR \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\le $$\end{document}≤ 1.57 = 2.5, GRWR \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\ge $$\end{document}≥ 2.13 = 2.5, total bilirubin ≥ 10.0 mg/dL = 2.0, INR ≥ 1.60 = 2.3, and aminotransferase > 2000 IU/L = 2.2. The mEAD model showed an AUC = 0.74 (95%CI = 0.66–0.82; p < 0.001) and AUC = 0.68 (95%CI = 0.58–0.88; p = 0.01) in the Training-Set and Validation-Set, respectively, outperforming conventional EAD in both cohorts (Training-Set: AUC = 0.64, 95%CI = 0.57–0.72; p = 0.001; Validation-Set: AUC = 0.52, 95%CI = 0.35–0.69, p = 0.87). Incorporation of graft weight in a composite multivariate model allowed for better prediction of patients who presented an aminotransferase peak > 2000 IU/L after LT (OR = 2.39, 95%CI = 1.47–3.93, p = 0.0005). The GRWR is important in determining early graft loss after adult LT, and the mEAD model is a useful predictive tool in this perspective, which may assist in improving the graft allocation process.

European Liver Transplant Registry: Donor and transplant surgery aspects of 16,641 liver transplantations in children

BACKGROUND AND AIMS

The European Liver Transplant Registry (ELTR) has collected data on liver transplant procedures performed in Europe since 1968.

APPROACH AND RESULTS

Over a 50-year period (1968-2017), clinical and laboratory data were collected from 133 transplant centers and analyzed retrospectively (16,641 liver transplants in 14,515 children). Data were analyzed according to three successive periods (A, before 2000; B, 2000-2009; and C, since 2010), studying donor and graft characteristics and graft outcome. The use of living donors steadily increased from A to C (A, n = 296 [7%]; B, n = 1131 [23%]; and C, n = 1985 [39%]; p = 0.0001). Overall, the 5-year graft survival rate has improved from 65% in group A to 75% in group B (p < 0.0001) and to 79% in group C (B versus C, p < 0.0001). Graft half-life was 31 years, overall; it was 41 years for children who survived the first year after transplant. The late annual graft loss rate in teenagers is higher than that in children aged <12 years and similar to that of young adults. No evidence for accelerated graft loss after age 18 years was found.

CONCLUSIONS

Pediatric liver transplantation has reached a high efficacy as a cure or treatment for severe liver disease in infants and children. Grafts that survived the first year had a half-life similar to standard human half-life. Transplantation before or after puberty may be the pivot-point for lower long-term outcome in children. Further studies are necessary to revisit some old concepts regarding transplant benefit (survival time) for small children, the role of recipient pathophysiology versus graft aging, and risk at transition to adult age.

Internal split liver transplants reduce the waiting list time for teenagers with a low calculated Model for End-stage Liver Disease score

BACKGROUND

Split liver transplantation allows for the simultaneous transplantation of two patients, typically a child and an adult, with a single organ. We report our experience with "internal splits" in which 10 pediatric patients from our institution were transplanted with five organs. We hypothesized that this would reduce the WL time for teenagers with a low calculated MELD score.

METHODS

A retrospective chart review of those 10 patients was done. Their WL time was compared with local, regional, and national data. P < .05 was considered significant.

RESULTS

The median age of the five primary recipients to whom the liver was first allocated was 2.3 years (0.7-7.4) (median weight 10.4 kg (8.4-17.7)). They received a segment 2-3 graft. Five "secondary" recipients (median age 17.4 years (16.6-18.9); median weight 66.2 kg (53.7-70.0)) were identified on our WL to receive the trisector graft. At transplant, their median calculated MELD score was 11 (8-20). Their mean WL time (241.6 ± 218.9 days) was significantly shorter than local (480.6 ± 833.6 days), regional (370.4 ± 563.4 days), and national patients (245.6 ± 465.4 days) with MELD ≤ 20 (P = .047). There was no significant difference between their WL time and that of patients with a MELD 8 ≤ x≤31 (equivalent to their median exception score, P = .63). Patient and graft survival was 100% for all 10 patients.

CONCLUSION

In our experience, simultaneous internal split liver transplantation allowed teenagers with a low calculated MELD score to be transplanted faster than patients with a similar score. Promoting the use of internal split liver transplantation could help reduce the pediatric waitlist mortality.

Considering extended right lobe grafts as major extended donor criteria in liver transplantation is justified

The outcomes of split-liver transplantation are controversial. This study compared outcomes and morbidity after extended right lobe liver transplantation (ERLT) and whole liver transplantation (WLT) in adults. MEDLINE and Web of Science databases were searched systematically and unrestrictedly for studies on ERLT and its impact on graft and patient survival, and postoperative complications. Graft loss and patient mortality odds ratios (OR) and 95% confidence intervals (CI) were assessed by meta-analyses using Mantel-Haenszel tests with a random-effects model. Vascular and biliary complications, primary nonfunction, 3-month, 1-, and 3-year graft and patient survival, and retransplantation after ERLT and WLT were analyzed. The literature search yielded 10 594 articles. After exclusion, 22 studies (n = 75 799 adult transplant patients) were included in the analysis. ERLT was associated with lower 3-month (OR = 1.43, 95% CI = 1.09-1.89, P = 0.01), 1-year (OR = 1.46, 95% CI = 1.08-1.97, P = 0.01), and 3-year (OR = 1.37, 95% CI = 1.01-1.84, P = 0.04) graft survival. WL grafts were less associated with retransplantation (OR = 0.57; 95% CI = 0.41-0.80; P < 0.01), vascular complications (OR = 0.53, 95% CI = 0.38-0.74, P < 0.01) and biliary complications (OR = 0.67; 95% CI = 0.47-0.95; P = 0.03). Considering ERLT as major Extended Donor Criteria is justified because ERL grafts are associated with vasculobiliary complications and the need for retransplantation, and have a negative influence on graft survival.

Liver Transplantation in Children: An Overview of Organ Allocation and Surgical Management

Liver transplantation is the standard treatment for children with end-stage liver disease, primary hepatic neoplasms, or liver-localized metabolic defects. Perioperative mortality is almost absent, and long-term survival exceeds 90%. Organ shortage is managed thanks to advances in organ retrieval techniques; living donation and partial liver transplantation almost eliminated waiting list mortality, thus leading to expanding indications for transplantation. The success of pediatric liver transplantation depends on the prompt and early referral of patients to transplant Centers and on the close and integrated multidisciplinary collaboration between pediatricians, hepatologists, surgeons, intensivists, oncologists, pathologists, coordinating nurses, psychologists, and social workers.

Current status of pediatric deceased donor liver transplantation: Lessons learned from a high-volume center in Japan where living donation remains predominant

BACKGROUND

In Japan, a recent gradual increase in deceased donor donation has expanded opportunities for pediatric patients to obtain deceased grafts.

METHODS

Forty-three children underwent deceased donor liver transplantation (DDLT) at our institute before February 2020. Twenty-five patients received a split or reduced graft and 18 patients received a whole graft. The clinical outcomes of DDLT were retrospectively analyzed.

RESULTS

The main organ resource was split/reduced grafts retrieved from adult donors; however, the number of whole grafts retrieved from pediatric donors has increased. The rates of major complications were similar in the two groups. The 5-year graft survival rate of patients who received a split/reduced graft (78.0%) was lower than that of patients who received a whole graft (88.9%; P = .40). The 3-year graft survival rates of patients who recently received a split/reduced graft and a whole graft improved to 92.3% and 91.7%, respectively.

CONCLUSIONS

The recent amendment of the organ allocation system, especially the introduction of pediatric prioritization, can effectively increase the chance to obtain deceased donor grafts for pediatric DDLT in Japan. The recent refinements in donor and recipient selection and in the surgical technique of split DDLT can improve the outcomes of pediatric DDLT in Japan.

Application of pediatric donors in split liver transplantation: Is there an age limit?

The experience of using pediatric donors in split liver transplant is exceedingly rare. We aim to investigate the outcomes of recipients receiving split pediatric grafts. Sixteen pediatric recipients receiving split liver grafts from 8 pediatric donors < 7 years were enrolled. The donor and recipient characteristics, perioperative course, postoperative complications, and graft and recipient survival rates were evaluated. The mean follow-up time was 8.0 ± 2.3 months. The graft and recipient survival rates were 100%. The liver function remained in the normal range at the end of the follow-up time in all recipients. No life-threatening complications were seen in these recipients, and the only surgery-related complication was portal vein stenosis in 1 recipient. Cytomegalovirus infection was the most common complication (62.5%). The transaminase level was significant higher in extended right lobe recipients in the early postoperative days, but the difference vanished at the end of first week; postoperative complications and graft and recipient survival rates did not differ between left and right graft recipients. Notably, the youngest split donor graft (2.7 years old) was associated with ideal recipient outcomes. Split liver transplant using well-selected pediatric donors is a promising strategy to expand pediatric donor source in well-matched recipients.