Predictive value of early postoperative lactate (<6†h) during normothermic machine perfusion and outcome after liver transplantation: results from a multicentre study.

BACKGROUND: Biomarkers with strong predictive capacity towards transplantation outcome for livers undergoing normothermic machine perfusion (NMP) are needed. We investigated lactate clearing capacity as a basic function of liver viability during the first 6 h of NMP. METHODS: A trial conducted in 6 high-volume transplant centres in Europe. All centres applied a back-to-base NMP approach with the OrganOx metra system. Perfusate lactate levels at start, 1, 2, 4 and 6 h of NMP were assessed individually and as area under the curve (AUC) and correlated with EAD (early allograft dysfunction), MEAF (model for early allograft function) and modified L-GrAFT (liver graft assessment following transplantation) scores. RESULTS: A total of 509 livers underwent ≥6 h of NMP before transplantation in 6 centres in the UK, Germany and Austria. The donor age was 53 (40-63) years (median, i.q.r.).The total NMP time was 10.8 (7.9-15.7) h. EAD occurred in 26%, MEAF was 4.72 (3.54-6.05) and L-GrAFT10 -0.96 (-1.52--0.32). Lactate at 1, 2 and 6 h correlated with increasing robustness with MEAF. Rather than a binary assessment with a cut-off value at 2 h, the actual 2 h lactate level correlated with the MEAF (P = 0.0306 versus P = 0.0002, Pearson r = 0.01087 versus r = 0.1734). The absolute lactate concentration at 6 h, the AUC of 0-6 h and 1-6 h (P < 0.0001, r = 0.3176) were the strongest predictors of MEAF. CONCLUSION: Lactate measured 1-6 h and lactate levels at 6 h correlate strongly with risk of liver allograft dysfunction upon transplantation. The robustness of predicting MEAF by lactate increases with perfusion duration. Monitoring lactate levels should be extended to at least 6 h of NMP routinely to improve clinical outcome.

Gastric sleeve as an extra-anatomical roux for biliary reconstruction in a pediatric third liver transplant.

BACKGROUND: Sir Roy Calne in 1976 described "Biliary reconstruction is the Achilles heel of liver transplantation," and it remains true. In some patients, such as those with short-gut syndrome and concomitant biliary atresia, neither duct to duct nor Roux biliary reconstruction is feasible. METHODS: We present a case of child's third liver transplant (LT), where an innovative extra-anatomical biliary bypass was created using a sleeve from greater curvature of the stomach. RESULTS: The patient is well nearly 10 years following the LT. CONCLUSIONS: This technique could prove to be an important addition to the armamentarium of a surgeon in difficult retransplants and in patients with short-gut syndrome as it provides a viable option with good long-term outcome.

COVID-19 Screening in the Pediatric Emergency Department.

BACKGROUND: Screening for COVID-19 infection in pediatrics is challenging as its clinical presentation may be asymptomatic or mimic other common childhood infections. We examined the use of a COVID-19 screening protocol (CSP) in the pediatric emergency department (PED) to determine the incidence of positive severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) polymerase chain reaction (PCR) tests in patients who are CSP+ and CSP-. METHODS: We conducted a retrospective cohort study of pediatric patients with SARS-CoV-2 testing completed in an urban tertiary care PED from November 1 to December 31, 2020. Demographics, CSP designation, test results, and disposition were compared. Statistical significance was determined using chi-square or a comparison of means. Sensitivity, specificity, negative predictive value (NPV), and positive predictive value (PPV) with 95% confidence intervals (CI) were calculated. RESULTS: A total of 1,613 patients had SARS-CoV-2 tests completed with 9.1% (N=147) having positive test results. Of 1,014 (62.9%) patients who were CSP+, 12.9% tested positive. Comparatively, 599 (37.1%) patients were CSP- with only 2.7% positive tests, p<0.0001. The sensitivity, specificity, NPV, and PPV of the CSP in all tested patients were 89.1%, 39.8%, 97.3%, and 12.9%, respectively. Of tested patients, 887 (55.0%) were admitted to the hospital and were more likely to be positive if CSP+, p≤0.001. Within the admitted group, 16.8% were admitted to the operating room, of whom 83.9% were CSP- with 4.0% testing positive for SARS-CoV-2. CONCLUSIONS: COVID-19 screening in the pediatric population is a useful modality to risk stratify most patients presenting to the PED for the purpose of selective testing and guiding personal protective equipment use. This may be particularly useful in low-resource settings.

Long-term outcomes of pediatric liver transplantation in acute liver failure vs end-stage chronic liver disease: A retrospective observational study.

BACKGROUND: Children with acute liver failure (ALF) who meet the criteria are eligible for super-urgent transplantation, whereas children with end-stage chronic liver disease (ESCLD) are usually transplanted electively. Pediatric liver trans plantation (PLT) in ALF and ESCLD settings has been well described in the literature, but there are no studies comparing the outcomes in these two groups. AIM: To determine if there is a difference in post-operative complications and survival outcomes between ALF and ESCLD in PLT. METHODS: This was a retrospective observational study of all primary PLTs performed at a single center between 2000 and 2019. ALF and ESCLD groups were compared for pretransplant recipient, donor and operative parameters, and post-operative outcomes including graft and patient survival. RESULTS: Over a 20-year study period, 232 primary PLTs were performed at our center; 195 were transplanted for ESCLD and 37 were transplanted for ALF. The ALF recipients were significantly older (median 8 years vs 5.4 years; P = 0.031) and heavier (31 kg vs 21 kg; P = 0.011). Living donor grafts were used more in the ESCLD group (34 vs 0; P = 0.006). There was no difference between the two groups concerning vascular complications and rejection, but there were more bile leaks in the ESCLD group. Post-transplant patient survival was significantly higher in the ESCLD group: 1-, 5-, and 10-year survival rates were 97.9%, 93.9%, and 89.4%, respectively, compared to 78.3%, 78.3%, and 78.3% in the ALF group (P = 0.007). However, there was no difference in 1-, 5-, and 10-year graft survival between the ESCLD and ALF groups (90.7%, 82.9%, 77.3% vs 75.6%, 72.4%, and 66.9%; P = 0.119). CONCLUSION: Patient survival is inferior in ALF compared to ESCLD recipients; the main reason is death in the 1st year post-PLT in ALF group. Once the ALF children overcome the 1st year after transplant, their survival stabilizes, and they have good long-term outcomes.

A multicenter randomized-controlled trial of hypothermic oxygenated perfusion (HOPE) for human liver grafts before transplantation.

BACKGROUND & AIMS: Machine perfusion is a novel method intended to optimize livers before transplantation. However, its effect on morbidity within a 1-year period after transplantation has remained unclear. METHODS: In this multicenter controlled trial, we randomly assigned livers donated after brain death (DBD) for liver transplantation (LT). Livers were either conventionally cold stored (control group), or cold stored and subsequently treated by 1-2 h hypothermic oxygenated perfusion (HOPE) before implantation (HOPE group). The primary endpoint was the occurrence of at least one post-transplant complication per patient, graded by the Clavien score of ≥III, within 1-year after LT. The comprehensive complication index (CCI), laboratory parameters, as well as duration of hospital and intensive care unit stay, graft survival, patient survival, and biliary complications served as secondary endpoints. RESULTS: Between April 2015 and August 2019, we randomized 177 livers, resulting in 170 liver transplantations (85 in the HOPE group and 85 in the control group). The number of patients with at least one Clavien ≥III complication was 46/85 (54.1%) in the control group and 44/85 (51.8%) in the HOPE group (odds ratio 0.91; 95% CI 0.50-1.66; p = 0.76). Secondary endpoints were also not significantly different between groups. A post hoc analysis revealed that liver-related Clavien ≥IIIb complications occurred less frequently in the HOPE group compared to the control group (risk ratio 0.26; 95% CI 0.07-0.77; p = 0.027). Likewise, graft failure due to liver-related complications did not occur in the HOPE group, but occurred in 7% (6 of 85) of the control group (log-rank test, p = 0.004, Gray test, p = 0.015). CONCLUSIONS: HOPE after cold storage of DBD livers resulted in similar proportions of patients with at least one Clavien ≥III complication compared to controls. Exploratory findings suggest that HOPE decreases the risk of severe liver graft-related events. IMPACT AND IMPLICATIONS: This randomized controlled phase III trial is the first to investigate the impact of hypothermic oxygenated perfusion (HOPE) on cumulative complications within a 12-month period after liver transplantation. Compared to conventional cold storage, HOPE did not have a significant effect on the number of patients with at least one Clavien ≥III complication. However, we believe that HOPE may have a beneficial effect on the quantity of complications per patient, based on its application leading to fewer severe liver graft-related complications, and to a lower risk of liver-related graft loss. The HOPE approach can be applied easily after organ transport during recipient hepatectomy. This appears fundamental for wide acceptance since concurring perfusion technologies need either perfusion at donor sites or continuous perfusion during organ transport, which are much costlier and more laborious. We conclude therefore that the post hoc findings of this trial should be further validated in future studies.

Novel Benchmark Values for Redo Liver Transplantation: Does the Outcome Justify the Effort?

OBJECTIVE: To define benchmark cutoffs for redo liver transplantation (redo-LT). BACKGROUND: In the era of organ shortage, redo-LT is frequently discussed in terms of expected poor outcome and wasteful resources. However, there is a lack of benchmark data to reliably evaluate outcomes after redo-LT. METHODS: We collected data on redo-LT between January 2010 and December 2018 from 22 high-volume transplant centers. Benchmark cases were defined as recipients with model of end stage liver disease (MELD) score ≤25, absence of portal vein thrombosis, no mechanical ventilation at the time of surgery, receiving a graft from a donor after brain death. Also, high-urgent priority and early redo-LT including those for primary nonfunction (PNF) or hepatic artery thrombosis were excluded. Benchmark cutoffs were derived from the 75th percentile of the medians of all benchmark centers. RESULTS: Of 1110 redo-LT, 373 (34%) cases qualified as benchmark cases. Among these cases, the rate of postoperative complications until discharge was 76%, and increased up to 87% at 1-year, respectively. One-year overall survival rate was excellent with 90%. Benchmark cutoffs included Comprehensive Complication Index CCI ® at 1-year of ≤72, and in-hospital and 1-year mortality rates of ≤13% and ≤15%, respectively. In contrast, patients who received a redo-LT for PNF showed worse outcomes with some values dramatically outside the redo-LT benchmarks. CONCLUSION: This study shows that redo-LT achieves good outcome when looking at benchmark scenarios. However, this figure changes in high-risk redo-LT, as for example in PNF. This analysis objectifies for the first-time results and efforts for redo-LT and can serve as a basis for discussion about the use of scarce resources.

A multicentre outcome analysis to define global benchmarks for donation after circulatory death liver transplantation.

BACKGROUND & AIMS: The concept of benchmarking is established in the field of transplant surgery; however, benchmark values for donation after circulatory death (DCD) liver transplantation are not available. Thus, we aimed to identify the best possible outcomes in DCD liver transplantation and to propose outcome reference values. METHODS: Based on 2,219 controlled DCD liver transplantations, collected from 17 centres in North America and Europe, we identified 1,012 low-risk, primary, adult liver transplantations with a laboratory MELD score of ≤20 points, receiving a DCD liver with a total donor warm ischemia time of ≤30 minutes and asystolic donor warm ischemia time of ≤15 minutes. Clinically relevant outcomes were selected and complications were reported according to the Clavien-Dindo-Grading and the comprehensive complication index (CCI). Corresponding benchmark cut-offs were based on median values of each centre, where the 75th-percentile was considered. RESULTS: Benchmark cases represented between 19.7% and 75% of DCD transplantations in participating centres. The 1-year retransplant and mortality rates were 4.5% and 8.4% in the benchmark group, respectively. Within the first year of follow-up, 51.1% of recipients developed at least 1 major complication (≥Clavien-Dindo-Grade III). Benchmark cut-offs were ≤3 days and ≤16 days for ICU and hospital stay, ≤66% for severe recipient complications (≥Grade III), ≤16.8% for ischemic cholangiopathy, and ≤38.9 CCI points 1 year after transplant. Comparisons with higher risk groups showed more complications and impaired graft survival outside the benchmark cut-offs. Organ perfusion techniques reduced the complications to values below benchmark cut-offs, despite higher graft risk. CONCLUSIONS: Despite excellent 1-year survival, morbidity in benchmark cases remains high. Benchmark cut-offs targeting morbidity parameters offer a valid tool to assess the protective value of new preservation technologies in higher risk groups and to provide a valid comparator cohort for future clinical trials. LAY SUMMARY: The best possible outcomes after liver transplantation of grafts donated after circulatory death (DCD) were defined using the concept of benchmarking. These were based on 2,219 liver transplantations following controlled DCD donation in 17 centres worldwide. Donor and recipient combinations with higher risk had significantly worse outcomes. However, the use of novel organ perfusion technology helped high-risk patients achieve similar outcomes as the benchmark cohort.

Predictors of patient and graft survival following pediatric liver transplantation: Long-term analysis of more than 300 cases from single centre.

BACKGROUND: Pediatric liver transplant (PLT) activity has flourished over time although with limited expansion in the graft pool. The study aims to identify pre-transplant factors that predict post-transplant patient and graft survival in the PLT population. METHODS: Retrospective review of PLTs at a single tertiary transplant unit from 2000 to 2019. Univariate and multivariate analyses of pre-transplant factors were performed to identify predictors of patient and graft survival. RESULTS: Two hundred and seventy-six patients received 320 PLTs. The most common cause of graft loss was hepatic artery thrombosis (n = 13, 29.6%). The most common cause of mortality was sepsis (n = 11, 29.7%). Univariate analysis showed that the following variables had a significant (p < .05) impact on patient survival: recipient age, weight, height, graft type (technical variant graft), transplant category (acute liver failure), the era of transplant, and invasive ventilation. The following variables had a significant (p < .05) impact on graft survival: recipient age, weight, height, transplant category (acute liver failure), and the era of transplant. Multivariate analysis precluded the era of transplant as the only significant factor for patient survival; patients transplanted after 2005 had significantly higher patient survival. No independent factor predicting graft survival was identified. For children transplanted after 2005, the only factor that predicted patient survival was pre-transplant invasive ventilation. CONCLUSIONS: Our study suggests that the learning curve and pre-transplant invasive ventilation in the recipient have a significant impact on patient survival. The traditional view of worse outcomes of smaller PLT candidates should be changed.

A coordinated national UK liver transplant program response, prioritizing waitlist recipients with the highest need, provided excellent outcomes during the first wave of the COVID-19 pandemic.

INTRODUCTION: Healthcare provision has been severely affected by COVID-19, with specific challenges in organ transplantation. Here, we describe the coordinated response to, and outcomes during the first wave, across all UK liver transplant (LT) centers. METHODS: Several policy changes affecting the liver transplant processes were agreed upon. These included donor age restrictions and changes to offering. A "high-urgency" (HU) category was established, prioritizing only those with UKELD > 60, HCC reaching transplant criteria, and others likely to die within 90 days. Outcomes were compared with the same period in 2018 and 2019. RESULTS: The retrieval rate for deceased donor livers (71% vs. 54%; P < .0001) and conversion from offer to completed transplant (63% vs. 48%; P < .0001) was significantly higher. Pediatric LT activity was maintained; there was a significant reduction in adult (42%) and total (36%) LT. Almost all adult LT were super-urgent (n = 15) or HU (n = 133). We successfully prioritized those with highest illness severity with no reduction in 90-day patient (P = .89) or graft survival (P = .98). There was a small (5% compared with 3%; P = .0015) increase in deaths or removals from the waitlist, mainly amongst HU cohort. CONCLUSIONS: We successfully prioritized LT recipients in highest need, maintaining excellent outcomes, and waitlist mortality was only marginally increased.

Hepatectomy risk assessment with functional magnetic resonance imaging (HEPARIM).

BACKGROUND: Post hepatectomy liver failure (PHLF) remains a significant risk in patients undergoing curative liver resection for cancer, however currently available PHLF risk prediction investigations are not sufficiently accurate. The Hepatectomy risk assessment with functional magnetic resonance imaging trial (HEPARIM) aims to establish if quantitative MRI biomarkers of liver function & perfusion can be used to more accurately predict PHLF risk and FLR function, measured against indocyanine green (ICG) liver function test. METHODS: HEPARIM is an observational cohort study recruiting patients undergoing liver resection of 2 segments or more, prior to surgery patients will have both Dynamic Gadoxetate-enhanced (DGE) liver MRI and ICG testing. Day one post op ICG testing is repeated and R15 compared to the Gadoxetate Clearance (GC) of the future liver remnant (FLR-GC) as measure by preoperative DGE- MRI which is the primary outcome, and preoperative ICG R15 compared to GC of whole liver (WL-GC) as a secondary outcome. Data will be collected from medical records, biochemistry, pathology and radiology reports and used in a multi-variate analysis to the value of functional MRI and derive multivariant prediction models for future validation. DISCUSSION: If successful, this test will potentially provide an efficient means to quantitatively assess FLR function and PHLF risk enabling surgeons to push boundaries of liver surgery further while maintaining safe practice and thereby offering chance of cure to patients who would previously been deemed inoperable. MRI has the added benefit of already being part of the routine diagnostic pathway and as such would have limited additional burden on patients time or cost to health care systems. (Hepatectomy Risk Assessment With Functional Magnetic Resonance Imaging - Full Text View - ClinicalTrials.gov , n.d.) TRIAL REGISTRATION: ClinicalTrials.gov, ClinicalTrials.gov NCT04705194 - Registered 12th January 2021 - Retrospectively registered.

Paediatric Liver Transplantation During COVID-19 Pandemic: Lessons Learned and Unanswered Questions.

COVID-19 pandemic has imposed many challenges on paediatric liver transplantation (PLT) services and has necessitated several adaptations in different stages of the process to ensure transplant centres can still deliver the proposed services in addition to protecting patients and staff against infection. This review article digs through the current literature to clarify the challenges imposed by SARS-CoV2 on PLT centres globally. It provides an overview of current practice as well as suggestions from experts in the field to overcome multiple obstacles. In paediatrics, the reaction to SARS-CoV2 may be less severe than that seen in the adult population, but this can change in view of newly discovered virus strains. Response of transplant centres to the current pandemic was variable depending on the anticipated risk and available resources. Telemedicine has helped PLT programmes to continue their activities while protecting patients, as well as staff against the risk of SARS-CoV2 virus. Further studies are needed to guide immunosuppression management in post-transplant infected candidates; answering this critical question will help PLT centres solve this dilemma.

Interactive Effects of Biosynthesized Nanocomposites and Their Antimicrobial and Cytotoxic Potentials.

The present study investigated the biosynthesis of silver (AgNPs), zinc oxide (ZnONPs) and titanium dioxide (TiO2NPs) nanoparticles using Aspergillusoryzae, Aspergillusterreus and Fusariumoxysporum. Nanocomposites (NCs) were successfully synthesized by mixing nanoparticles using a Sonic Vibra-Cell VC/VCX processor. A number of analytical techniques were used to characterize the synthesized biological metal nanoparticles. Several experiments tested biologically synthesized metal nanoparticles and nanocomposites against two types of human pathogenic bacteria, including Gram-positive Staphylococcus aureus and methicillin-resistant Staphylococcus aureus (MRSA), and Gram-negative Escherichia coli and Pseudomonasaeruginosa. Additionally, the antitumor activity in HCT-116 cells (colonic carcinoma) was also evaluated. Significant antimicrobial effects of various synthesized forms of nanoparticles and nanocomposites against E. coli and P. aeruginosa bacteria were detected. Various synthesized biogenic forms of nanoparticles and nanocomposite (9.0 to 29 mm in diameter) had high antibacterial activity and high antitumor activity against HCT-116 cells (colonic carcinoma) with IC50 values of 0.7-100 µg/mL. Biosynthesized NPs are considered an alternative to large-scale biosynthesized metallic nanoparticles and nanocomposites, are simple and cost effective, and provide stable nanomaterials.

Design, Analysis, and Pitfalls of Clinical Trials Using Ex Situ Liver Machine Perfusion: The International Liver Transplantation Society Consensus Guidelines.

BACKGROUND: Recent trials in liver machine perfusion (MP) have revealed unique challenges beyond those seen in most clinical studies. Correct trial design and interpretation of data are essential to avoid drawing conclusions that may compromise patient safety and increase costs. METHODS: The International Liver Transplantation Society, through the Special Interest Group "DCD, Preservation and Machine Perfusion," established a working group to write consensus statements and guidelines on how future clinical trials in liver perfusion should be designed, with particular focus on relevant clinical endpoints and how different techniques of liver perfusion should be compared. Protocols, abstracts, and full published papers of clinical trials using liver MP were reviewed. The use of a simplified Grading of Recommendations Assessment, Development, and Evaluation working group (GRADE) system was attempted to assess the level of evidence. The working group presented its conclusions at the International Liver Transplantation Society consensus conference "DCD, Liver Preservation, and Machine Perfusion" held in Venice, Italy, on January 31, 2020. RESULTS: Twelve recommendations were proposed with the main conclusions that clinical trials investigating the effect of MP in liver transplantation should (1) make the protocol publicly available before the start of the trial, (2) be adequately powered, and (3) carefully consider timing of randomization in function of the primary outcome. CONCLUSIONS: There are issues with using accepted primary outcomes of liver transplantation trials in the context of MP trials, and no ideal endpoint could be defined by the working group. The setup of an international registry was considered vital by the working group.

Does the Role of A Rapid Triage Provider Improve Pain Control in an Academic Pediatric Emergency Department?

Pediatric pain control in the emergency department (ED) remains problematic. This quantifiable metric may be positively affected by the utilization of a rapid triage provider (RTP). This is a retrospective case control study of pediatric patients requiring either ketorelac intravenous (IV) or morphine IV for painful conditions. Patients in the control group were managed according to standard nursing-driven triage process. Patients in the RTP group were seen by the standard triage team as well as by the RTP.We identified 114 patients who required IV pain medications. The mean time from arrival to pain medication administration for the RTP group as compared with the control group was 47 and 64 minutes (P = 0.02). Similarly, the mean time from arrival to IV pain medication order placement was 15 and 43 minutes (P < 0.01). An RTP improves pain control in the pediatric ED via more efficient order placement and IV pain medication administration.