Graft Survival In Liver Transplantation Research Articles

A narrative review: predicting liver transplant graft survival using artificial intelligence modeling.

Liver transplantation is the only treatment for patients with liver failure. As demand for liver transplantation grows, it remains a challenge to predict the short- and long-term survival of the liver graft. Recently, artificial intelligence models have been used to evaluate the short- and long-term survival of the liver transplant. To make the models more accurate, suitable liver transplantation characteristics must be used as input to train them. In this narrative review, we reviewed studies concerning liver transplantations published in the PubMed, Web of Science, and Cochrane databases between 2017 and 2022. We picked out 17 studies using our selection criteria and analyzed them, evaluating which medical characteristics were used as input for creation of artificial intelligence models. In eight studies, models estimating only short-term liver graft survival were created, while in five of the studies, models for the prediction of only long-term liver graft survival were built. In four of the studies, artificial intelligence algorithms evaluating both the short- and long-term liver graft survival were created. Medical characteristics that were used as input in reviewed studies and had the biggest impact on the accuracy of the model were the recipient's age, recipient's body mass index, creatinine levels in the recipient's serum, recipient's international normalized ratio, diabetes mellitus, and recipient's model of end-stage liver disease score. To conclude, in order to define important liver transplantation characteristics that could be used as an input for artificial intelligence algorithms when predicting liver graft survival, more models need to be created and analyzed, in order to fully support the results of this review.

Influence of socioeconomic factors on liver transplant survival outcomes in patients with autoimmune liver disease in the United States

Introduction and ObjectivesAutoimmune liver diseases (AILDs): autoimmune hepatitis (AIH), primary biliary cholangitis (PBC), and primary sclerosing cholangitis (PSC) have different survival outcomes after liver transplant (LT). Outcomes are influenced by factors including disease burden, medical comorbidities, and socioeconomic variables. Materials and MethodsUsing the United Network for Organ Sharing database (UNOS), we identified 13,702 patients with AILDs listed for LT between 2002 and 2021. Outcomes of interest were waitlist removal, post-LT patient survival, and post- LT graft survival. A stepwise multivariate analysis was performed adjusting for transplant recipient gender, race, diabetes mellitus, model for end-stage liver disease (MELD) score, and additional social determinants including the presence of education, reliance on public insurance, working for income, and U.S. citizenship status. ResultsLack of college education and having public insurance increased the risk of waitlist removal (HR, 1.13; 95 % CI, 1.05–1.23, and HR, 1.09; 95 % CI, 1.00–1.18; respectively), and negatively influenced post-LT patient survival (HR, 1.16; 95 % CI, 1.06–1.26, and HR, 1.15; 95 % CI, 1.06–1.25; respectively) and graft survival (HR, 1.13; 95 % CI, 1.05–1.23, and HR, 1.15; 95 % CI, 1.06–1.25; respectively). Not working for income proved to have the greatest detrimental impact on both patient survival (HR, 1.41; 95 % CI, 1.24–1.6) and graft survival (HR, 1.21; 95 % CI, 1.09–1.35). ConclusionsOur study highlights that lack of college education and public insurance have a detrimental impact on waitlist mortality, patient survival, and graft survival. Not working for income negatively affects post-LT survival outcomes. Not having U.S. citizenship does not affect survival outcomes in AILDs patients.

Hypothermic oxygenated perfusion in liver transplantation: a meta-analysis of randomized controlled trials and matched studies.

Hypothermic oxygenated machine perfusion (HOPE) is a novel organ-preservation technology designed to optimize organ quality. However, the effects of HOPE on morbidity and mortality after liver transplantation remain unclear. This meta-analysis evaluated the potential benefits of HOPE in liver transplantation. The Embase, Web of Science, PubMed, Cochrane Library, and Scopus databases were searched for articles published up to 15 June 2023 (updated on 12 August 2023). Mean differences (MDs), risk ratios (RRs), and 95% confidence intervals were calculated. Eleven studies encompassing five randomized controlled trials and six matched studies were included, with a total of 1000 patients. HOPE did not reduce the incidence of major postoperative complications (RR 0.80), primary non-function (PNF) (RR 0.54), reperfusion syndrome (RR 0.92), hepatic artery thrombosis (RR 0.92), renal replacement therapy (RR 0.98), length of hospital stay (MD, -1.38 days), 1-year recipient death (RR 0.67), or intensive care unit stay (MD, 0.19 days) after liver transplantation. HOPE reduced the incidence of biliary complications (RR 0.74), non-anastomotic biliary strictures (NAS) (RR 0.34), early allograft dysfunction (EAD) (RR 0.54), and acute rejection (RR 0.54). In addition, HOPE improved the retransplantation (RR 0.42) and 1-year graft loss rates (RR 0.38). Compared with static cold storage (SCS), HOPE can reduce the incidence of biliary complications, NAS, EAD, and acute rejection and retransplantation rate after liver transplantation and improve the 1-year graft loss rate. These findings suggest that HOPE, when compared to SCS, can contribute to minimizing complications and enhancing graft survival in liver transplantation. Further research is needed to investigate long-term outcomes and confirm the promising advantages of HOPE in liver transplantation settings.

Graft Survival in Liver Transplantation: An Artificial Neuronal Network Assisted Analysis of the Importance of Comorbidities.

Liver transplant represents a widespread therapeutic option for patients with end-stage liver failure. Up to now, most of the scores describing the probability of liver graft survival have shown poor predictive performance. With this in mind, the present study seeks to analyze the predictive value of recipient comorbidities on liver graft survival within the first year. The study included prospectively collected data from patients who received a liver transplant at our center from 2010 to 2021. A predictive model was then developed through an Artificial Neural Network that included the parameters associated with graft loss as identified by the Spanish Liver Transplant Registry report and comorbidities with prevalence >2% present in our study cohort. Most patients in our study were men (75.5%); mean age was 54.8 ± 9.6 years. The main cause of transplant was cirrhosis (86.7%), and 67.4% of patients had some associated comorbidities. Graft loss due to retransplant or death with dysfunction occurred in 14% of cases. Of all the variables analyzed, we found 3 comorbidities associated with graft loss (as shown by informative value and normalized informative value, respectively): antiplatelet and/or anticoagulants treatments (0.124 and 78.4%), previous immunosuppression (0.110 and 69.6%), and portal thrombosis (0.105 and 66.3%). Remarkably, our model showed a C statistic of 0.745 (95% CI, 0.692-0.798; asymptotic P < .001), which was higher than others found in previous studies. Our model identified key parameters that may influence graft loss, including specific recipient comorbidities. The use of artificial intelligence methods could reveal connections that may be overlooked by conventional statistics.

Low resistive index on doppler ultrasound predicts worse graft survival in liver transplantation

Background: Although liver transplantation (LT) outcomes have improved significantly over the last decades, early post-transplant vascular complications, such as hepatic arterial thrombosis (HAT), are still associated with an elevated risk of graft failure. Doppler Ultrasound (DUS) is a non-invasive, semi-quantitative method capable of detecting vascular abnormalities by estimating the resistance to arterial blood flow, quantified through the Resistive Index (RI). In order to detect early acute HAT, DUS is performed on the first post-transplant week. The aim of this study was to evaluate the association of RI parameters of DUS performed on the first post-transplant week with graft survival of transplanted livers.

Prediction of Graft Survival Post-liver Transplantation by L-GrAFT Risk Score Model, EASE Score, MEAF Scoring, and EAD.

Background: Early allograft dysfunction (EAD) is correlated with poor patient or graft survival in liver transplantation. However, the power of distinct definitions of EAD in prediction of graft survival is unclear.Methods: This retrospective, single-center study reviewed data of 677 recipients undergoing orthotopic liver transplant between July 2015 and June 2020. The following EAD definitions were compared: liver graft assessment following transplantation (L-GrAFT) risk score model, early allograft failure simplified estimation score (EASE), model for early allograft function (MEAF) scoring, and Olthoff criteria. Risk factors for L-GrAFT7 high risk group were evaluated with univariate and multivariable logistic regression analysis.Results: L-GrAFT7 had a satisfied C-statistic of 0.87 in predicting a 3-month graft survival which significantly outperformed MEAF (C-statistic = 0.78, P = 0.01) and EAD (C-statistic = 0.75, P < 0.001), respectively. L-GrAFT10, EASE was similar to L-GrAFT7, and they had no statistical significance in predicting survival. Laboratory model for end-stage liver disease score and cold ischemia time are risk factors of L-GrAFT7 high-risk group.Conclusion: L-GrAFT7 risk score is capable for better predicting the 3-month graft survival than the MEAF and EAD in a Chinese cohort, which might standardize assessment of early graft function and serve as a surrogate endpoint in clinical trial.

Conditional probability of graft survival in liver transplantation using donation after circulatory death grafts - a retrospective study.

The use of livers from donation after circulatory death (DCD) is historically characterized by increased rates of biliary complications and inferior short-term graft survival (GS) compared to donation after brain death (DBD) allografts. This study aimed to evaluate the dynamic prognostic impact of DCD livers to reveal whether they remain an adverse factor even after patients survive a certain period following liver transplant (LT). This study used 74961 LT patients including 4065 DCD LT in the scientific registry of transplant recipients from 2002-2017. The actual, 1 and 3-year conditional hazard ratio (HR) of 1-year GS in DCD LT were calculated using a conditional version of Cox regression model. The actual 1-, 3-, and 5-year GS of DCD LT recipients were 83.3%, 73.3%, and 66.3%, which were significantly worse than those of DBD (all P<0.01). Actual, 1-, and 3-year conditional HR of 1-year GS in DCD compared to DBD livers were 1.87, 1.49, and 1.39, respectively. Graft loss analyses showed that those lost to biliary related complications were significantly higher in the DCD group even 3years after LT. National registry data demonstrate the protracted higher risks inherent to DCD liver grafts in comparison to their DBD counterparts, despite survival through the early period after LT. These findings underscore the importance of judicious DCD graft selection at individual center level to minimize the risk of long-term biliary complications.

Transplant Outcomes of Donation After Circulatory Death Livers Recovered With Versus Without Premortem Heparin Administration.

Premortem heparin administration during donation after circulatory death (DCD) organ recovery is thought to optimize liver perfusion. However, premortem heparinization is not universally practiced in the United States and limited data exist regarding its utility. US registry data were accessed between January 1, 2003, and March 10, 2017, and 2 cohorts were ascertained: (1) DCD donor livers recovered for transplantation (n=5495) and (2) liver-only adult transplant recipients of DCD livers (n=3754). Exclusions were donor unknown heparin status (n=40), positive donor hepatitis B surface antigen (n=4) and hepatitis C virus (n=120) serologies, and for the outcomes analysis, livers placed outside the United States (n=10). Discard rates and graft outcomes were examined from cohorts 1 and 2, respectively. Of 5495 DCD livers recovered for transplant, 589 (10.7%) donors did not receive premortem heparin (no heparin) and the remaining 4906 (89.3%) received heparin (heparin). Liver discard was similar between the no heparin (30.6%) and heparin groups (30.8%; P=0.90). Heparin status was not associated with liver discard on multivariate analysis (adjusted odds ratio, 0.97; 95% confidence interval [CI], 0.80-1.18 P=0.76). The cumulative probability of overall graft survival was lower in the no heparin group relative to the heparin group (P<0.05), and this finding persisted on multivariate analysis. No heparin group transplants had an 18% higher hazard of overall graft failure compared with those that received heparin (adjusted hazard ratio, 1.18; 95% CI, 1.01-1.38; P<0.05). In conclusion, organ recovery heparin administration status was not associated with liver discard. Failure to pretreat organ donors with premortem heparin correlates with worse liver transplant graft survival compared with heparin-treated livers.

Peroxiredoxins in inflammatory liver diseases and ischemic/reperfusion injury in liver transplantation

Peroxiredoxins (Prxs) belong to the superfamily of thiol-dependent peroxidases, and remove reactive oxygen species (ROS) and other oxidative stress products. The expression and activity of Prxs can be substantially affected by stimuli from the microenvironment, and in turn regulate cytokine secretion in the context of inflammation in both peroxidase-dependent and -independent pathways. Prxs translocate to mitochondria and are hyperoxidized during acute liver damage, and attenuate intracellular ROS accumulation through their peroxidase activity. In particularly, Prx1 modulates the microenvironment in liver injuries by reducing adhesion molecule expression in vascular endothelial cells and inhibiting the inflammatory response and adhesion of macrophages. Prxs have potent prosurvival effects against ROS in ischemic/reperfusion (I/R) injury, but Prxs released from necrotic cells increase secretion of inflammatory cytokines by macrophages through TLR2 and 4 activation, which promotes cell death. Prxs can be used as biomarkers to evaluate I/R injury and predict graft survival in liver transplantation. Prxs are modulated in various types of chronic hepatitis and hepatosteatosis, and mediate disease progression. Alcohol administration increases oxidization and inactivation of Prxs in mice because of oxidative stress. In conclusion, Prxs are essential mediators and biomarkers in inflammatory liver diseases and I/R injury.

Looking inward: The impact of operative time on graft survival after liver transplantation

Operative time often has been cited as an important factor for postoperative outcomes. Despite this belief, most efforts to improve liver transplant outcomes have largely focused on only patient and donor factors, and little attention has been paid on operative time. The primary objective of this project was to determine the impact of operative time on graft survival after liver transplant. A retrospective review of 2,877 consecutive liver transplants performed at a single institution was studied. Data regarding recipient, donor, and operative characteristics, including detailed granular operative times were collected prospectively and retrospectively reviewed. Using an instrument variable approach, Cox multivariate modeling was performed to assess the impact of operative time without the confounding of known and unknown variables. Of the 2,396 patients who met the criteria for review, the most important factors determining liver transplant graft survival included recipient history of Hepatitis C (hazard ratio 1.45, P=.02), donor age (hazard ratio 1.23, P=.03), use of liver graft from donation after cardiac death donor (hazard ratio 1.50, P<.01), and operative time (hazard ratio 1.26, P=.01). In detailed analysis of stages of the liver transplant operation, the time interval from incision to anhepatic phase was associated with graft survival (hazard ratio 1.33; P=.02). Using a novel instrument variable approach, we demonstrate that operative time (in particular, the time interval from incision to anhepatic time) has a significant impact on graft survival. It also seems that some of this efficiency is under the influence of the transplant surgeon.

Hepatic gadoxetic acid uptake as a measure of diffuse liver disease: Where are we?

3 J. Magn. Reson. Imaging 2017;45:646-659.

Role of donor hemodynamic trajectory in determining graft survival in liver transplantation from donation after circulatory death donors

Donation after circulatory death (DCD) donors show heterogeneous hemodynamic trajectories following withdrawal of life support. Impact of hemodynamics in DCD liver transplant is unclear, and objective measures of graft viability would ease transplant surgeon decision making and inform safe expansion of the donor organ pool. This retrospective study tested whether hemodynamic trajectories were associated with transplant outcomes in DCD liver transplantation (n = 87). Using longitudinal clustering statistical techniques, we phenotyped DCD donors based on hemodynamic trajectory for both mean arterial pressure (MAP) and peripheral oxygen saturation (SpO2 ) following withdrawal of life support. Donors were categorized into 3 clusters: those who gradually decline after withdrawal of life support (cluster 1), those who maintain stable hemodynamics followed by rapid decline (cluster 2), and those who decline rapidly (cluster 3). Clustering outputs were used to compare characteristics and transplant outcomes. Cox proportional hazards modeling revealed hepatocellular carcinoma (hazard ratio [HR] = 2.53; P = 0.047), cold ischemia time (HR = 1.50 per hour; P = 0.027), and MAP cluster 1 were associated with increased risk of graft loss (HR = 3.13; P = 0.021), but not SpO2 cluster (P = 0.172) or donor warm ischemia time (DWIT; P = 0.154). Despite longer DWIT, MAP and SpO2 clusters 2 showed similar graft survival to MAP and SpO2 clusters 3, respectively. In conclusion, despite heterogeneity in hemodynamic trajectories, DCD donors can be categorized into 3 clinically meaningful subgroups that help predict graft prognosis. Further studies should confirm the utility of liver grafts from cluster 2. Liver Transplantation 22 1469-1481 2016 AASLD.

Early graft dysfunction and mortality rate in marginal donor liver transplantation.

To determine the effect of marginal donor livers on mortality and graft survival in liver transplantation (LT) recipients. Donors with any 1 of following were considered marginal donors: age ≥65 years, sodium level ≥ 165 mmol/L and cold ischemia time ≥ 12 h. Donors were classified according to the donor risk index (DRI) < 1.7 and ≥ 1.7. The transplant recipients' model for end-stage liver disease (MELD) scores were considered low if < 20 and high if ≥ 20. Early graft dysfunction (EGD) and mortality rate were evaluated. During the study period 47 patients underwent cadaveric LT. The mean age of the donors and recipients was 45 years (range: 5-72 years) and 46 years (range: 4-66 years), respectively. In all, there were 15 marginal donors and 18 donors with a DRI > 1.7. In total, 4 LT patients that received livers from marginal donors and 5 that received livers from donors with a DRI ≥ 1.7 had EGD. Among the recipients of marginal livers, 5 died, versus 4 of the recipients of standard livers. There was no significant difference in EGD or mortality rate between the patients that received livers from marginal donors or those with a DRI ≥ 1.7 and patients that received standard donor livers. Marginal and DRI ≥ 1.7 donors negatively affected LT outcomes, but not significantly.

Does Lymphocyte Cross-Matching Predict Acute Rejection and Graft Survival in Liver Transplantation?

IntroductionThe role of lymphocyte cross-matches (LCM) remains controversial in the liver transplant field. The aim of this study was to correlate the risk for acute rejection episodes and graft survival in liver transplantation with pretransplant LCM results. Patients and MethodsWe enrolled 184 adult liver transplantation patients, excluding pediatric and second grafts. The 129 living donor and 55 deceased donor liver transplantations were divided into 2 groups: LCM (+); (n = 20) and LCM (−); (n = 164). ResultsThere were no differences in the demographic features, such as gender and recipient age, original disease, Model for End-Stage Liver Disease score, donor type, number of human leukocyte antigen mismatches, and cold ischemia times. There were no hyperacute rejection episodes in the LCM (+) group. Also, posttransplant complications such as acute rejection episode, biliary complication, or hepatic artery thrombosis were not different. Acute rejection episodes occurred in 5.0% of the LCM (+) group and 15.2% of the LCM (−) group (P = .317). Bile duct complications after transplantation arose in 20.0% of the LCM (+) group and in 32.9% of the LCM (−) group (P = .312). The 2 groups showed no difference in graft survival rate analyzed by the Kaplan–Meier method according to LCM results. ConclusionPretransplant LCM results were not associated with overall graft survival or acute rejection episodes in this study.

Preoperative factors as predictors of blood product transfusion requirements in orthotopic liver transplantation

Intraoperative transfusion can affect the chance of graft survival in liver transplantation, a complicated operation with massive blood loss. Verification of factors that are predictive of intraoperative blood loss and transfusion increases the quality of anesthesia management. To assess use of blood and blood products between 2002 and 2008 and to evaluate factors associated with blood loss and requirement for blood products in adult patients undergoing orthotopic liver transplantation via piggyback technique. Medical charts and anesthesia records from 261 eligible adult recipients of an orthotopic liver transplant between March 2002 and May 2008 were reviewed. Shiraz Liver Transplantation Center, the only active liver transplantation center in Iran. Potential influencing factors in blood loss and transfusion, including sex, preoperative hemoglobin level, international normalized ratio, primary diagnosis, platelet count, creatinine level, Model for End-Stage Liver Disease (MELD) score, central venous pressure, and total anesthesia time, were measured and subjected to multivariable analysis. Mean blood loss was 54.2 (SD, 47.9) mL/kg, the mean (SD) for amounts of blood products transfused was 25.3 (19.5) mL/kg for packed red blood cells, 2.6 (3.3) units for fresh frozen plasma, and 1.7 (3.1) units for platelets. Seven recipients (2.7%) underwent transplantation without intraoperative transfusion of red blood cells, whereas 25 patients (9.6%) received more than 10 units of red blood cells intraoperatively. Multivariable analysis showed that no preoperative factor was a predictor of blood loss or requirement for intraoperative transfusion. Transfusion of fresh frozen plasma and packed red blood cells was significantly lower in 2005, 2006, 2007, and 2008 than in 2003 to 2004 (P < .001).

Preoperative Factors as Predictors of Blood Product Transfusion Requirements in Orthotopic Liver Transplantation

Intraoperative transfusion can affect the chance of graft survival in liver transplantation, a complicated operation with massive blood loss. Verification of factors that are predictive of intraoperative blood loss and transfusion increases the quality of anesthesia management. To assess use of blood and blood products between 2002 and 2008 and to evaluate factors associated with blood loss and requirement for blood products in adult patients undergoing orthotopic liver transplantation via piggyback technique. Medical charts and anesthesia records from 261 eligible adult recipients of an orthotopic liver transplant between March 2002 and May 2008 were reviewed. Shiraz Liver Transplantation Center, the only active liver transplantation center in Iran. Potential influencing factors in blood loss and transfusion, including sex, preoperative hemoglobin level, international normalized ratio, primary diagnosis, platelet count, creatinine level, Model for End-Stage Liver Disease (MELD) score, central venous pressure, and total anesthesia time, were measured and subjected to multivariable analysis. Mean blood loss was 54.2 (SD, 47.9) mL/kg, the mean (SD) for amounts of blood products transfused was 25.3 (19.5) mL/kg for packed red blood cells, 2.6 (3.3) units for fresh frozen plasma, and 1.7 (3.1) units for platelets. Seven recipients (2.7%) underwent transplantation without intraoperative transfusion of red blood cells, whereas 25 patients (9.6%) received more than 10 units of red blood cells intraoperatively. Multivariable analysis showed that no preoperative factor was a predictor of blood loss or requirement for intraoperative transfusion. Transfusion of fresh frozen plasma and packed red blood cells was significantly lower in 2005, 2006, 2007, and 2008 than in 2003 to 2004 (P < .001).

The Use of Hepatitis B Core Antibody-Positive Donor Livers Does Not Appear to Have a Deleterious Effect on Graft Survival in Liver Transplantation for Hepatitis C

Introduction The use of hepatitis B core antibody-positive donor livers (HBcAb +) has steadily increased. According to a recent multivariate analysis of United Network for Organ Sharing (UNOS) data, there was no significant increase in the risk of using these donors. The increased risk among the hepatitis C virus (HCV)-positive subgroup noted in a univariate model disappeared upon multivariate analysis. However, deeper scrutiny may show that HCV-positive recipients may be at increased risk with HBcAb + donor livers, as they require simultaneous treatment with two antiviral regimens there may be deleterious interactions between the two viruses. Thus, the issue of HBcAb + donors for HCV-positive recipients merits more detailed analysis. Methods Using UNOS registry data of all liver transplantations performed during the Model for End-Stage Liver Disease era from February 2002 through November 2007, we analyzed graft survival using Kaplan-Meier and Cox regression analyses. Results Of the 12,543 HCV-positive recipients, 2,543 received HBcAb − livers and 853 received HBcAb + livers. While Kaplan- Meier analysis showed significantly lower graft survival among HCV-negative recipients of HBcAb + livers ( P = .0001), there was no significant effect on graft survival among the HCV-positive population ( P = .2). To detect an early effect in HCV-positive recipients, we examined 1-year graft survival, observing no significant difference ( P = .3). To exclude a possible late effect, we examined graft survival in the HCV-positive population conditional upon surviving at least 1 year after transplantation; no significant difference was observed ( P = .6). The elimination of potentially confounding codiagnoses, such as hepatitis B virus, alcoholism, acute graft failure, and hepatocellular cancer did not alter the findings. On univariate analysis, the lack of a significant effect persisted among the HCV population. However, the significant effect observed in the univariate model for the HCV-negative population became insignificant when combined with other risk factors in the multivariate model. Conclusion The use of HBcAb + livers in recipients with HCV did not appear to have a significant impact on grat survival.

Significance of Portosystemic Shunt on Graft Survival in Liver Transplantation: A Rat Model

Aims Distal splenorenal shunt effectively controls bleeding from esophageal and gastric varices but has a different effect on liver transplantation. This study sought to develop an animal model in rats to mimic the recipient with a portosystemic shunt and to investigate its hemodynamic consequences on liver transplantation. Methods We prepared 5 groups of allogeneic or syngeneic rat liver transplantation models with versus without portosystemic shunt, to investigate its effects on graft survival and portal flow. To explore the effects of excessive portal flow on graft survival in small-for-size liver transplantation, we transplanted partial liver grafts into syngeneic recipients. Results In allogeneic combinations, graft survival among the shunt group was shortened compared with their control counterparts. The graft survival of the large shunt group was significantly lower than that of a small shunt or without shunt group in a syngeneic liver transplantation model. Portal blood pressure of the large shunt group was significantly lower than that of the small shunt group. In contrast, excessive portal flow resulted in dysfunction of liver graft in small-for-size liver transplantation. Conclusions These results suggested that reduction in portal flow by portosystemic shunt lead to an acceleration of acute rejection and subsequent liver graft dysfunction, but it may be applicable to regulate the excessive portal flow in small-for-size transplantations. This study showed a valuable model mimicking the recipient with a portosystemic shunt.

Consequences of Cold-Ischemia Time on Primary Nonfunction and Patient and Graft Survival in Liver Transplantation: A Meta-Analysis

IntroductionThe ability to preserve organs prior to transplant is essential to the organ allocation process.ObjectiveThe purpose of this study is to describe the functional relationship between cold-ischemia time (CIT) and primary nonfunction (PNF), patient and graft survival in liver transplant.MethodsTo identify relevant articles Medline, EMBASE and the Cochrane database, including the non-English literature identified in these databases, was searched from 1966 to April 2008. Two independent reviewers screened and extracted the data. CIT was analyzed both as a continuous variable and stratified by clinically relevant intervals. Nondichotomous variables were weighted by sample size. Percent variables were weighted by the inverse of the binomial variance.ResultsTwenty-six studies met criteria. Functionally, PNF% = −6.678281+0.9134701*CIT Mean+0.1250879*(CIT Mean−9.89535)2−0.0067663*(CIT Mean−9.89535)3, r2 = .625, , p<.0001. Mean patient survival: 93 % (1 month), 88 % (3 months), 83 % (6 months) and 83 % (12 months). Mean graft survival: 85.9 % (1 month), 80.5 % (3 months), 78.1 % (6 months) and 76.8 % (12 months). Maximum patient and graft survival occurred with CITs between 7.5–12.5 hrs at each survival interval. PNF was also significantly correlated with ICU time, % first time grafts and % immunologic mismatches.ConclusionThe results of this work imply that CIT may be the most important pre-transplant information needed in the decision to accept an organ.

No Improvement in Long-Term Liver Transplant Graft Survival in the Last Decade: An Analysis of the UNOS Data

We analyzed change in outcomes during two successive 5-year periods (period I = 1992-1996 vs period II = 1997-2002) among 35 186 deceased adult liver transplant recipients reported to the United Network for Organ Sharing (UNOS) Registry. The 5-year graft survival was 67.4% in the first period and 67.5% in the second, though the 1-year survival had improved from 81.0 to 83.5%. Comparison of blended survival rates during the two study periods showed decreased long-term graft survival in period II, explicable by an increased number of hepatitis C virus cirrhosis (HCV) patients and an increase in patients with HCV antibodies (HCVab) during this later period. Analysis wherein these patients with HCV were excluded revealed the same long-term graft survival during both periods. Non-HCV patients who had HCVab also had worse 5-year graft survival. We conclude that hepatitis C prevented improved outcomes during period II and that improved, more effective, treatment for hepatitis C virus would have great positive impact on overall survival of liver transplant recipients.