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BACKGROUND & AIM: We aimed to assess long-term outcome after transplantation of HOPE-treated donor livers based on real-world data (i.e., IDEAL-D stage 4). METHODS: In this international, multicentre, observational cohort study, we collected data from adult recipients of a HOPE-treated liver transplanted between January 2012 and December 2021. Analyses were stratified for brain-dead (DBD) and circulatory-dead (DCD) donor livers, sub-divided by their respective risk categories. The primary outcome was death-censored graft survival. Secondary outcomes included the incidence of primary non-function (PNF) and ischemic cholangiopathy (IC). RESULTS: We report on 1202 liver transplantations (64% DBD) performed at 22 European centres. For DBD, a total number of 99 benchmark (8%), 176 standard (15%), and 493 extended-criteria (41%) cases were included. For DCD, 117 transplants were classified as low-risk (10%), 186 as high-risk (16%), and 131 as futile (11%), with significant risk profile variations among centres. Actuarial 1-, 3-, and 5-year death-censored graft survival for DBD and DCD was 95%, 92%, and 91%, vs. 92%, 87%, and 81%, respectively (logrank p=0.003). Within DBD and DCD-strata, death-censored graft survival was similar among risk groups (logrank p=0.26, p=0.99). Graft loss due to PNF or IC was 2.3% and 0.4% (DBD), and 5% and 4.1% (DCD). CONCLUSIONS: This study shows excellent 5-year survival after transplantation of HOPE-treated DBD and DCD livers with low rates of graft loss due to PNF or IC, irrespective of their individual risk profile. HOPE-treatment has now reached IDEAL-D stage 4, which further supports the implementation of HOPE in routine clinical practice. IMPACT AND IMPLICATIONS: This study demonstrates the excellent long-term performance of HOPE-treatment of DCD and DBD liver grafts irrespective of their individual risk profile in a real-world setting, outside the evaluation of randomized controlled trials. While previous studies have established safety, feasibility, and efficacy against the current standard, according to the IDEAL-D evaluation framework, HOPE-treatment has now reached the final IDEAL-D Stage 4, which further supports the implementation of HOPE in routine clinical practice. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT05520320.
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Background: Ex situ machine perfusion is increasingly used to preserve and assess donor livers before transplantation. Compared with traditional static cold storage (SCS), machine perfusion exposes livers to an additional risk of microbial contamination. However, information on the risk of microbial transmission during machine perfusion is lacking. Methods: All livers that underwent either hypothermic oxygenated machine perfusion (HOPE) or normothermic machine perfusion (NMP) in our center between September 2021 and September 2023, and during which samples were taken from SCS fluid and/or machine perfusion solution for microbiological examination, were included in this retrospective, observational clinical study. Microbial transmission was examined from SCS fluid to machine perfusion solution fluid and, subsequently, to recipients of these livers. Results: A total of 90 cases of liver machine perfusion were included: 59 HOPE and 31 NMP. SCS preservation fluid cultures before HOPE or NMP were positive for at least 1 microorganism in 52% of the cases. After HOPE, there were no cases of positive machine perfusion fluid or evidence of microbial transmission to the recipients. After NMP, in 1 (3%) patient Escherichia coli was grown from abdominal drain fluid, the same bacterial strain that was also grown from the SCS preservation fluid before NMP. This E coli was resistant to the antibiotics that are routinely added to the NMP perfusion fluid. Conclusions: The risk of microbial transmission after machine perfusion is very low but not absent. We recommend routine sampling of machine perfusion fluid at the end of the procedure for microbiological analysis.
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BACKGROUND: Liver transplantation is used for treating end-stage liver disease, fulminant hepatitis, and oncological malignancies and organ shortage is a major limiting factor worldwide. The use of grafts based on extended donor criteria have become internationally accepted. Oxygenated machine perfusion technologies are the most recent advances in organ transplantation; however, it is only applied after a period of cold ischemia. Due to its high cost, we aimed to use a novel device, OxyFlush®, based on oxygenation of the preservation solution, applied during liver procurement targeting the maintenance of ATP during static cold storage (SCS). METHODS: Twenty patients were randomly assigned to the OxyFlush or control group based on a 1:1 ratio. In the OxyFlush group, the perfusion solution was oxygenated with OxyFlush® device while the control group received a non-oxygenated solution. Liver and the common bile duct (CBD) biopsies were obtained at three different time points. The first was at the beginning of the procedure, the second during organ preparation, and the third after total liver reperfusion. Biopsies were analyzed, and adenosine triphosphate (ATP) levels and histological scores of the liver parenchyma and CBD were assessed. Postoperative laboratory tests were performed. RESULTS: OxyFlush® was able to maintain ATP levels during SCS and improved the damage caused by the lack of oxygen in the CBD. However, OxyFlush® did not affect laboratory test results and histological findings of the parenchyma. CONCLUSION: We present a novel low-cost device that is feasible and could represent a valuable tool in organ preservation during SCS.
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PURPOSE OF REVIEW: With changing donor characteristics (advanced age, obesity), an increase in the use of extended criteria donor (ECD) livers in liver transplantation is seen. Machine perfusion allows graft viability assessment, but still many donor livers are considered nontransplantable. Besides being used as graft viability assessment tool, ex situ machine perfusion offers a platform for therapeutic strategies to ameliorate grafts prior to transplantation. This review describes the current landscape of graft repair during machine perfusion. RECENT FINDINGS: Explored anti-inflammatory therapies, including inflammasome inhibitors, hemoabsorption, and cellular therapies mitigate the inflammatory response and improve hepatic function. Cholangiocyte organoids show promise in repairing the damaged biliary tree. Defatting during normothermic machine perfusion shows a reduction of steatosis and improved hepatobiliary function compared to nontreated livers. Uptake of RNA interference therapies during machine perfusion paves the way for an additional treatment modality. SUMMARY: The possibility to repair injured donor livers during ex situ machine perfusion might increase the utilization of ECD-livers. Application of defatting agents is currently explored in clinical trials, whereas other therapeutics require further research or optimization before entering clinical research.
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Sobrevivência de Enxerto , Transplante de Fígado , Preservação de Órgãos , Perfusão , Humanos , Perfusão/métodos , Perfusão/instrumentação , Transplante de Fígado/efeitos adversos , Transplante de Fígado/métodos , Animais , Preservação de Órgãos/métodos , Preservação de Órgãos/instrumentação , Fígado/irrigação sanguínea , Fígado/cirurgia , Resultado do Tratamento , Seleção do Doador , Doadores de Tecidos/provisão & distribuição , Anti-InflamatóriosRESUMO
PURPOSE OF REVIEW: In an attempt to reduce waiting list mortality in liver transplantation, less-than-ideal quality donor livers from extended criteria donors are increasingly accepted. Predicting the outcome of these organs remains a challenge. Machine perfusion provides the unique possibility to assess donor liver viability pretransplantation and predict postreperfusion organ function. RECENT FINDINGS: Assessing liver viability during hypothermic machine perfusion remains challenging, as the liver is not metabolically active. Nevertheless, the levels of flavin mononucleotide, transaminases, lactate dehydrogenase, glucose and pH in the perfusate have proven to be predictors of liver viability. During normothermic machine perfusion, the liver is metabolically active and in addition to the perfusate levels of pH, transaminases, glucose and lactate, the production of bile is a crucial criterion for hepatocyte viability. Cholangiocyte viability can be determined by analyzing bile composition. The differences between perfusate and bile levels of pH, bicarbonate and glucose are good predictors of freedom from ischemic cholangiopathy. SUMMARY: Although consensus is lacking regarding precise cut-off values during machine perfusion, there is general consensus on the importance of evaluating both hepatocyte and cholangiocyte compartments. The challenge is to reach consensus for increased organ utilization, while at the same time pushing the boundaries by expanding the possibilities for viability testing.
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Transplante de Fígado , Fígado , Preservação de Órgãos , Perfusão , Humanos , Perfusão/métodos , Perfusão/efeitos adversos , Transplante de Fígado/efeitos adversos , Fígado/cirurgia , Fígado/metabolismo , Preservação de Órgãos/métodos , Preservação de Órgãos/efeitos adversos , Sobrevivência de Tecidos , Doadores de Tecidos , Hepatócitos/metabolismo , Hepatócitos/transplante , Animais , Seleção do Doador , Bile/metabolismo , Sobrevivência Celular , Biomarcadores/metabolismo , Valor Preditivo dos Testes , Isquemia Fria/efeitos adversosRESUMO
INTRODUCTION: Intraoperative blood loss and postoperative hemorrhage affect outcomes after liver resection. GATT-Patch is a new flexible, pliable hemostatic sealant patch comprising fibrous gelatin carrier impregnated with N-hydroxy-succinimide polyoxazoline. We evaluated safety and performance of the GATT-Patch for hemostasis at the liver resection plane. METHODS: Adult patients undergoing elective open liver surgery were recruited in three centers. GATT-Patch was used for minimal to moderate bleeding at the liver resection plane. The primary endpoint was hemostasis of the first-treated bleeding site at 3 min versus a prespecified performance goal of 65.4%. RESULTS: Two trial stages were performed: I (n = 8) for initial safety and II (n = 39) as the primary outcome cohort. GATT-Patch was applied in 47 patients on 63 bleeding sites. Median age was 60.0 (range 25-80) years and 70% were male. Most (66%) surgeries were for colorectal cancer metastases. The primary endpoint was met in 38 out of 39 patients (97.4%; 95% confidence interval: 84.6%-99.9%) versus 65.4% (P < 0.001). Of all the 63 bleeding sites, hemostasis was 82.7% at 30, 93.7% at 60, and 96.8% at 180 s. No reoperations for rebleeding or device-related issues occurred. CONCLUSIONS: When compared to a performance goal derived from state-of-the-art hemostatic agents, GATT-Patch for the treatment of minimal to moderate bleeding during liver surgery successfully and quickly achieved hemostasis with acceptable safety outcomes. (ClinicalTrials.gov Identifier: NCT04819945).
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Perda Sanguínea Cirúrgica , Hepatectomia , Humanos , Masculino , Pessoa de Meia-Idade , Feminino , Idoso , Adulto , Hepatectomia/efeitos adversos , Hepatectomia/métodos , Idoso de 80 Anos ou mais , Perda Sanguínea Cirúrgica/estatística & dados numéricos , Perda Sanguínea Cirúrgica/prevenção & controle , Hemostasia Cirúrgica/métodos , Hemostasia Cirúrgica/instrumentação , Hemostáticos/administração & dosagem , Hemostáticos/uso terapêutico , Hemostáticos/efeitos adversos , Resultado do Tratamento , Gelatina/efeitos adversos , Gelatina/administração & dosagem , Estudos Prospectivos , Neoplasias Hepáticas/cirurgia , Neoplasias Hepáticas/secundárioRESUMO
Background: Normothermic machine perfusion (NMP) is used to preserve and test donor livers before transplantation. During NMP, the liver is metabolically active and produces waste products, which are released into the perfusate. In this study, we describe our simplified and inexpensive setup that integrates continuous renal replacement therapy (CRRT) with NMP for up to 7 d. We also investigated if the ultrafiltrate could be used for monitoring perfusate concentrations of small molecules such as glucose and lactate. Methods: Perfusate composition (urea, osmolarity, sodium, potassium, chloride, calcium, magnesium, phosphate, glucose, and lactate) was analyzed from 56 human NMP procedures without CRRT. Next, in 6 discarded human donor livers, CRRT was performed during NMP by integrating a small dialysis filter (0.2 m2) into the circuit to achieve continuous ultrafiltration combined with continuous fluid substitution for up to 7 d. Results: Within a few hours of NMP without CRRT, a linear increase in osmolarity and concentrations of urea and phosphate to supraphysiological levels was observed. After integration of CRRT into the NMP circuit, the composition of the perfusate was corrected to physiological values within 12 h, and this homeostasis was maintained during NMP for up to 7 d. Glucose and lactate levels, as measured in the CRRT ultrafiltrate, were strongly correlated with perfusate levels (râ =â 0.997, Pâ <â 0.001 and râ =â 0.999, Pâ <â 0.001, respectively). Conclusions: The integration of CRRT into the NMP system corrected the composition of the perfusate to near-physiological values, which could be maintained for up to 7 d. The ultrafiltrate can serve as an alternative to the perfusate to monitor concentrations of small molecules without potentially compromising sterility.
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Background: Liver transplantation is traditionally performed around the clock to minimize organ ischemic time. However, the prospect of prolonging preservation times holds the potential to streamline logistics and transform liver transplantation into a semi-elective procedure, reducing the need for nighttime surgeries. Dual hypothermic oxygenated machine perfusion (DHOPE) of donor livers for 1-2 h mitigates ischemia-reperfusion injury and improves transplant outcomes. Preclinical studies have shown that DHOPE can safely extend the preservation of donor livers for up to 24 h. Methods: We conducted an IDEAL stage 2 prospective clinical trial comparing prolonged (≥4 h) DHOPE to conventional (1-2 h) DHOPE for brain-dead donor livers, enabling transplantation the following morning. Liver allocation to each group was based on donor hepatectomy end times. The primary safety endpoint was a composite of all serious adverse events (SAE) within 30 days after transplantation. The primary feasibility endpoint was defined as the number of patients assigned and successfully receiving a prolonged DHOPE-perfused liver graft. Trial registration at: WHO International Clinical Trial Registry Platform, number NL8740. Findings: Between November 1, 2020 and July 16, 2022, 24 patients were enrolled. The median preservation time was 14.5 h (interquartile range [IQR], 13.9-15.5) for the prolonged group (n = 12) and 7.9 h (IQR, 7.6-8.6) for the control group (n = 12; p = 0.01). In each group, three patients (25%; 95% CI 3.9-46%, p = 1) experienced a SAE. Markers of ischemia-reperfusion injury and oxidative stress in both perfusate and recipients were consistently low and showed no notable discrepancies between the two groups. All patients assigned to either the prolonged group or control group successfully received a liver graft perfused with either prolonged DHOPE or control DHOPE, respectively. Interpretation: This first-in-human clinical trial demonstrates the safety and feasibility of DHOPE in prolonging the preservation time of donor livers to enable daytime transplantation. The ability to extend the preservation window to up to 20 h using hypothermic oxygenated machine preservation at a 10 °C temperature has the potential to reshape the landscape of liver transplantation. Funding: University Medical Center Groningen, the Netherlands.
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Neoplasias dos Ductos Biliares , Colangiocarcinoma , Tumor de Klatskin , Humanos , Tumor de Klatskin/cirurgia , Tumor de Klatskin/patologia , Colangiocarcinoma/cirurgia , Colangiocarcinoma/patologia , Ductos Biliares Intra-Hepáticos/patologia , Neoplasias dos Ductos Biliares/cirurgia , Neoplasias dos Ductos Biliares/patologia , Cirrose Hepática/cirurgia , Cirrose Hepática/patologia , Hepatectomia , Estudos Retrospectivos , Resultado do TratamentoRESUMO
BACKGROUND: Surgical resection for perihilar cholangiocarcinoma (pCCA) is associated with high operative risks. Impaired liver regeneration in patients with pre-existing liver disease may contribute to posthepatectomy liver failure (PHLF) and postoperative mortality. This study aimed to determine the incidence of hepatic steatosis and fibrosis and their association with PHLF and 90-day postoperative mortality in pCCA patients. METHODS: Patients who underwent a major liver resection for pCCA were included in the study between 2000 and 2021 from three tertiary referral hospitals. Histopathologic assessment of hepatic steatosis and fibrosis was performed. The primary outcomes were PHLF and 90-day mortality. RESULTS: Of the 401 included patients, steatosis was absent in 334 patients (83.3%), mild in 58 patients (14.5%) and moderate to severe in 9 patients (2.2%). There was no fibrosis in 92 patients (23.1%), periportal fibrosis in 150 patients (37.6%), septal fibrosis in 123 patients (30.8%), and biliary cirrhosis in 34 patients (8.5%). Steatosis (≥ 5%) was not associated with PHLF (odds ratio [OR] 1.36; 95% confidence interval [CI] 0.69-2.68) or 90-day mortality (OR 1.22; 95% CI 0.62-2.39). Neither was fibrosis (i.e., periportal, septal, or biliary cirrhosis) associated with PHLF (OR 0.76; 95% CI 0.41-1.41) or 90-day mortality (OR 0.60; 95% CI 0.33-1.06). The independent risk factors for PHLF were preoperative cholangitis (OR 2.38; 95% CI 1. 36-4.17) and future liver remnant smaller than 40% (OR 2.40; 95% CI 1.31-4.38). The independent risk factors for 90-day mortality were age of 65 years or older (OR 2.40; 95% CI 1.36-4.23) and preoperative cholangitis (OR 2.25; 95% CI 1.30-3.87). CONCLUSION: In this study, no association could be demonstrated between hepatic steatosis or fibrosis and postoperative outcomes after resection of pCCA.
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Neoplasias dos Ductos Biliares , Colangite , Fígado Gorduroso , Tumor de Klatskin , Cirrose Hepática Biliar , Falência Hepática , Neoplasias Hepáticas , Humanos , Idoso , Tumor de Klatskin/cirurgia , Cirrose Hepática Biliar/complicações , Cirrose Hepática Biliar/cirurgia , Complicações Pós-Operatórias , Hepatectomia/efeitos adversos , Falência Hepática/etiologia , Cirrose Hepática/complicações , Neoplasias Hepáticas/cirurgia , Colangite/complicações , Colangite/cirurgia , Neoplasias dos Ductos Biliares/complicações , Estudos RetrospectivosRESUMO
Normothermic machine perfusion (NMP) after static cold storage is increasingly used for preservation and assessment of human donor livers prior to transplantation. Biliary viability assessment during NMP reduces the risk of post-transplant biliary complications. However, understanding of molecular changes in the biliary system during NMP remains incomplete. We performed an in-depth, unbiased proteomics analysis of bile collected during sequential hypothermic machine perfusion, rewarming and NMP of 55 human donor livers. Longitudinal analysis during NMP reveals proteins reflective of cellular damage at early stages, followed by upregulation of secretory and immune response processes. Livers with bile chemistry acceptable for transplantation reveal protein patterns implicated in regenerative processes, including cellular proliferation, compared to livers with inadequate bile chemistry. These findings are reinforced by detection of regenerative gene transcripts in liver tissue before machine perfusion. Our comprehensive bile proteomics and liver transcriptomics data sets provide the potential to further evaluate molecular mechanisms during NMP and refine viability assessment criteria.
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Sistema Biliar , Transplante de Fígado , Humanos , Bile/metabolismo , Proteoma/metabolismo , Doadores Vivos , Fígado , PerfusãoRESUMO
INTRODUCTION: Outflow obstruction is a rare but critical vascular complication in liver transplantation, which may lead to graft loss and mortality. We report a case of caval vein outflow obstruction due to retrohepatic compression after living donor liver transplantation (LDLT), which was managed by temporary implantation of a vena cava filter. PRESENTATION OF CASE: A 63-year-old male with end stage liver disease presented with caval vein outflow obstruction and massive ascites 12 days after right lobe LDLT. We opted for a minimally invasive approach and implanted a vena cava filter at the compressed site through transjugular route. The patient's ascites drainage significantly decreased and graft function maintained stable after the intervention. On day 50 posttransplant, the filter was successfully removed and the patient was discharged without complications. DISCUSSION: Outflow obstruction after liver transplantation can result from anastomotic stenosis, graft size mismatch, thrombosis or compression of the outflow tract. Various management strategies have been employed both peri- and posttransplant, ranging from surgical interventions to minimally-invasive techniques. The treatment strategy should be tailored to the individual case, considering the timing of presentation and the specific cause for the obstruction. CONCLUSION: We successfully managed a case of compressive outflow obstruction by temporary implantation of a vena cava filter after LDLT. The vena cava filter was safely removed under angiography.
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BACKGROUND: Currently, no practical definition of potentially resectable, borderline or unresectable perihilar cholangiocarcinoma (pCCA) is available. Aim of this study was to define criteria to categorize patients for use in a future neoadjuvant or induction therapy study. METHOD: Using the modified DELPHI method, hepatobiliary surgeons from all tertiary referral centers in the Netherlands were invited to participate in this study. During five online meetings, predefined factors determining resectability and additional factors regarding surgical resectability and operability were discussed. RESULTS: The five online meetings resulted in 52 statements. After two surveys, consensus was reached in 63% of the questions. The main consensus included a definition regarding potential resectability. 1) Clearly resectable: no vascular involvement (≤90°) of the future liver remnant (FLR) and expected feasibility of radical biliary resection. 2) Clearly unresectable: non-reconstructable venous and/or arterial involvement of the FLR or no feasible radical biliary resection. 3) Borderline resectable: all patients between clearly resectable and clearly unresectable disease. CONCLUSION: This DELPHI study resulted in a practical and applicable resectability, or more accurate, an explorability classification, which can be used to categorize patients for use in future neoadjuvant therapy studies.
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BACKGROUND & AIMS: Biliary atresia (BA) is an obstructive cholangiopathy that initially affects the extrahepatic bile ducts (EHBDs) of neonates. The etiology is uncertain, but evidence points to a prenatal cause. Fetal tissues have increased levels of hyaluronic acid (HA), which plays an integral role in fetal wound healing. The objective of this study was to determine whether a program of fetal wound healing is part of the response to fetal EHBD injury. METHODS: Mouse, rat, sheep, and human EHBD samples were studied at different developmental time points. Models included a fetal sheep model of prenatal hypoxia, human BA EHBD remnants and liver samples taken at the time of the Kasai procedure, EHBDs isolated from neonatal rats and mice, and spheroids and other models generated from primary neonatal mouse cholangiocytes. RESULTS: A wide layer of high molecular weight HA encircling the lumen was characteristic of the normal perinatal but not adult EHBD. This layer, which was surrounded by collagen, expanded in injured ducts in parallel with extensive peribiliary gland hyperplasia, increased mucus production and elevated serum bilirubin levels. BA EHBD remnants similarly showed increased HA centered around ductular structures compared with age-appropriate controls. High molecular weight HA typical of the fetal/neonatal ducts caused increased cholangiocyte spheroid growth, whereas low molecular weight HA induced abnormal epithelial morphology; low molecular weight HA caused matrix swelling in a bile duct-on-a-chip device. CONCLUSION: The fetal/neonatal EHBD, including in human EHBD remnants from Kasai surgeries, demonstrated an injury response with prolonged high levels of HA typical of fetal wound healing. The expanded peri-luminal HA layer may swell and lead to elevated bilirubin levels and obstruction of the EHBD. IMPACT AND IMPLICATIONS: Biliary atresia is a pediatric cholangiopathy associated with high morbidity and mortality rates; although multiple etiologies have been proposed, the fetal response to bile duct damage is largely unknown. This study explores the fetal pathogenesis after extrahepatic bile duct damage, thereby opening a completely new avenue to study therapeutic targets in the context of biliary atresia.
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Ductos Biliares Extra-Hepáticos , Atresia Biliar , Humanos , Animais , Camundongos , Ratos , Criança , Ovinos , Atresia Biliar/patologia , Ductos Biliares Extra-Hepáticos/patologia , Feto/patologia , Cicatrização , BilirrubinaRESUMO
Background and Aims: Previous trials comparing cyclosporine and tacrolimus after liver transplantation (LT) showed conflicting results. Most used trough monitoring for cyclosporine (C0), leading to less accurate dosing than with 2-h monitoring (C2). Only one larger trial compared C2 with tacrolimus based on trough level (T0) after LT, with similar treated biopsy-proven acute rejection (tBPAR) and graft loss, while a smaller trial had less tBPAR with C2 compared to T0. Therefore, it is still unclear which calcineurin inhibitor is preferred after LT. We aimed to demonstrate superior efficacy (tBPAR), tolerability, and safety of C2 or T0 after first LT. Methods: Patients after first LT were randomized to C2 or T0. tBPAR, patient- and graft survival, safety and tolerability were the main endpoints, with analysis by Fisher test, Kaplan-Meier survival analysis and log-rank test. Results: In intention-to-treat analysis 84 patients on C2 and 85 on T0 were included. Cumulative incidence of tBPAR C2 vs. T0 was 17.7% vs. 8.4% at 3 months (p=0.104), and 21.9% vs. 9.7% at 6 and 12 months (p=0.049). One-year cumulative mortality C2 vs. T0 was 15.5% vs. 5.9% (p=0.049) and graft loss 23.8% vs. 9.4% (p=0.015). Serum triglyceride and LDL-cholesterol was lower with T0 than with C2. Incidence of diarrhea in T0 vs, C2 was 64% vs. 31% (p≤0.001), with no other differences in safety and tolerability. Conclusions: In the first year after LT immunosuppression with T0 leads to less tBPAR and better patient-/re-transplant-free survival as compared to C2.
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BACKGROUND: Normothermic machine perfusion (NMP) of donor livers allows for new diagnostic and therapeutic strategies. As the liver produces most of the haemostatic proteins, coagulation assays such as the International Normalised Ratio (INR) performed in perfusate may be useful to assess hepatocellular function of donor livers undergoing NMP. However, high concentrations of heparin and low levels of fibrinogen may affect coagulation assays. METHODS: Thirty donor livers that underwent NMP were retrospectively included in this study, of which 18 were subsequently transplanted. We measured INRs in perfusate in presence or absence of exogenously added fibrinogen and/or polybrene. Additionally, we prospectively included 14 donor livers that underwent NMP (of which 11 were transplanted) and measured INR using both a laboratory coagulation analyser and a point-of-care device. RESULTS: In untreated perfusate samples, the INR was above the detection limit in all donor livers. Addition of both fibrinogen and polybrene was required for adequate INR assessment. INRs decreased over time and detectable perfusate INR values were found in 17/18 donor livers at the end of NMP. INR results were similar between the coagulation analyser and the point-of-care device, but did not correlate with established hepatocellular viability criteria. CONCLUSIONS: Most of the donor livers that were transplanted showed a detectable perfusate INR at the end of NMP, but samples require processing to allow for INR measurements using laboratory coagulation analysers. Point-of-care devices bypass this need for processing. The INR does not correlate with established viability criteria and might therefore have additional predictive value.
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Transplante de Fígado , Humanos , Transplante de Fígado/métodos , Coeficiente Internacional Normatizado , Brometo de Hexadimetrina/metabolismo , Estudos Retrospectivos , Preservação de Órgãos/métodos , Doadores Vivos , Fígado/metabolismo , Perfusão/métodos , Fatores de Coagulação Sanguínea/metabolismo , Fibrinogênio/metabolismoRESUMO
BACKGROUND: Normothermic machine perfusion (NMP) is used for the viability assessment of high-risk donor livers before transplantation. The production of hemostatic proteins is one of the major synthetic functions of the liver. The objective of this study was to measure the concentration and functionality of hemostatic proteins concentration in the NMP perfusate of human donor livers. METHODS: Thirty-six livers that underwent NMP for viability assessment were included in this study. Perfusate samples taken during NMP (start, 150 min, and 300 min) were used for the measurement of antigen and activity levels of hemostatic proteins (factors II, VII, and X; fibrinogen; plasminogen; antithrombin; tissue plasminogen activator; von Willebrand factor; and proteins induced by vitamin K absence). The antigen levels were correlated with hepatocellular function according to previously proposed individual hepatocellular viability criteria: lactate clearance and perfusate pH. RESULTS: Antigen levels of hemostatic proteins reached subphysiological levels in the NMP perfusate. Hemostatic proteins that were produced during NMP were at least partially active. All livers produced all hemostatic proteins tested within 150 min of NMP. Hemostatic protein concentrations did not significantly correlate with perfusate lactate and perfusate pH after 150 min of NMP. CONCLUSIONS: All livers produce functional hemostatic proteins during NMP. The generation of a functional hemostatic system in NMP perfusate confirms the need for adequate anticoagulation of the perfusate to avoid generation of (micro)thrombi that may harm the graft.
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With the increasing number of accepted candidates on waiting lists worldwide, there is an urgent need to expand the number and the quality of donor livers. Dynamic preservation approaches have demonstrated various benefits, including improving liver function and graft survival, and reducing liver injury and post-transplant complications. Consequently, organ perfusion techniques are being used in clinical practice in many countries. Despite this success, a proportion of livers do not meet current viability tests required for transplantation, even with the use of modern perfusion techniques. Therefore, devices are needed to further optimise machine liver perfusion - one promising option is to prolong machine liver perfusion for several days, with ex situ treatment of perfused livers. For example, stem cells, senolytics, or molecules targeting mitochondria or downstream signalling can be administered during long-term liver perfusion to modulate repair mechanisms and regeneration. Besides, today's perfusion equipment is also designed to enable the use of various liver bioengineering techniques, to develop scaffolds or for their re-cellularisation. Cells or entire livers can also undergo gene modulation to modify animal livers for xenotransplantation, to directly treat injured organs or to repopulate such scaffolds with "repaired" autologous cells. This review first discusses current strategies to improve the quality of donor livers, and secondly reports on bioengineering techniques to design optimised organs during machine perfusion. Current practice, as well as the benefits and challenges associated with these different perfusion strategies are discussed.