We have previously shown that patients listed for orthotopic liver transplantation (OLT) in United Network for Organ Sharing Region 4 (Texas and Oklahoma) have higher waitlist mortality rates when residing more than 30 miles from specialized liver transplant centers (LTC). Considering that findings might only be exclusive for this region with its peculiarities in terms of having the highest land surface extensions, lowest population densities, and largest rural populations. We investigated the entire OLT patient population in the United States to assess if our previous regional findings are nationally validated and if a rural, micropolitan, or metropolitan residence location affects outcome of waitlisted OLT patients in the nation.

Patients waiting for OLT in the United States from 2002 to 2012 were stratified by distance from the patients' residence to LTC and by Rural Urban Commuting Area (RUCA) codes classification. Statistical analyses were performed to evaluate risk of mortality on the waitlist and the likelihood to receive an OLT using a Cox proportional hazards model and a generalized additive model with a logistic link.

Survival time and probability of death while on the waitlist for OLT using distance to LTC showed significant increased risk with the distance (P = 0.001 and P < 0.0001, respectively). At the same time, using RUCA classification as the variable did not show significance (P = 0.14 and P = 0.73, respectively).

Distance from an LTC is a risk factor of mortality on the waitlist for OLT, whereas RUCA classification is not a significant factor.

US pediatric transplant candidates have limited access to lung transplant due to the small number of donors within current geographic boundaries, leading to assertions that the current lung allocation system does not adequately serve pediatric patients. We hypothesized that broader geographic sharing of pediatric (adolescent, 12-17 years; child, <12 years) donor lungs would increase pediatric candidate access to transplant. We used the thoracic simulated allocation model to simulate broader geographic sharing. Simulation 1 used current allocation rules. Simulation 2 offered adolescent donor lungs across a wider geographic area to adolescents. Simulation 3 offered child donor lungs across a wider geographic area to adolescents. Simulation 4 combined simulations 2 and 3. Simulation 5 prioritized adolescent donor lungs to children across a wider geographic area. Simulation 4 resulted in 461 adolescent transplants per 100 patient-years on the waiting list (range 417-542), compared with 206 (range 180-228) under current rules. Simulation 5 resulted in 388 adolescent transplants per 100 patient-years on the waiting list (range 348-418) and likely increased transplant rates for children. Adult transplant rates, waitlist mortality, and 1-year posttransplant mortality were not adversely affected. Broader geographic sharing of pediatric donor lungs may increase pediatric candidate access to lung transplant.

We evaluated the efficacy of initial and follow-up hepatic venous pressure gradient (HVPG), models of end-stage liver disease (MELD), and MELD-Na for predicting the survival of patients with decompensated liver cirrhosis (LC).

MELD with/without Na score and HVPG have been important predictors of mortality in patients with LC.

Between January 2006 and 2011, a total of 57 patients with decompensated LC, all of whom underwent >2 HVPG measurements for the confirmation of propranolol dosing, were enrolled. MELD and MELD-Na scores were calculated on the day of HVPG measurement. The prognostic accuracy of the initial and follow-up HVPG, MELD, and MELD-Na were analyzed, and independent factors for mortality were evaluated.

Ten patients (17.5%) died from LC. Initial HVPG (0.883), initial MELD-Na (0.877), follow-up HVPG (0.829), and follow-up MELD-Na (0.802) showed good area under the receiver operating characteristic curve scores in predicting 1-year mortality. In predicting 2-year mortality, only follow-up HVPG (0.821, cut-off value 18 mm Hg) showed good score. Overall area under the receiver operating characteristic curves (initial and follow-up) were 0.843 and 0.864 in HVPG, 0.721 and 0.674 in MELD, and 0.762 and 0.715 in MELD-Na, respectively. In the Cox regression analysis, only follow-up HVPG (P=0.02; odds ratio, 1.11) was associated with mortality.

The efficacy of HVPG for predicting mortality is excellent compared with that of MELD or MELD-Na. Therefore, aside from the confirmation of adequate propranolol dosing, HVPG may be needed for predicting the survival of patients with decompensated LC.

On 16 December 2006, most Eurotransplant countries changed waiting time oriented liver allocation policy to the urgency oriented Model for End-stage Liver Disease (MELD) system. There are limited data on the effects of this policy change within the Eurotransplant community.

A total of 154 patients who had undergone deceased donor liver transplantation (LT) were retrospectively analyzed in three time periods: period A (1-year pre-MELD, n = 42) versus period B (1-year post-MELD, n = 52) versus period C (2 years after MELD implementation, n = 60).

The median MELD score at the time of LT increased from 16.3 points in period A to 22.4 and 20.4 in periods B and C, respectively (p = 0.007). Waitlist mortality decreased from 18.4% in period A to 10.4% and 9.4% in periods B and C, respectively (p = 0.015). Three-month mortality did not change significantly (10% each for periods A, B and C). One-year survival was 84% for the MELD 6-19 group compared with 81% in the MELD 20-29 group and 74% in the MELD ≥30 group (p = 0.823). Analyzing MELD score and previously described prognostic scores [i.e. survival after liver transplantation (SALT) score and donor-MELD (D-MELD) score] with regard to 1-year survival, only a high risk SALT score was predictive (p = 0.038). In our center, 2 years after implementation of the MELD system, waitlist mortality decreased, while 90-day mortality did not change significantly.

Up to now, only the SALT score proved to be of prognostic relevance post-transplant.

Liver transplantation is the most effective treatment for many patients with chronic end-stage liver disease. The discrepancy between the number of donor organs and potential recipients causes marked pre-transplantation mortality and consequently optimal rationalization of organ allocation is essential. The Model for End-Stage Liver Disease (MELD) is an objective and easily reproducible prognostic index of mortality based on three simple analytical variables: bilirubin and serum creatinine and the prothrombin time/International Normalized Ratio (INR) of protrombine time. The implementation of MELD as an organ allocation system has reduced mortality on the waiting list without affecting post-transplantation survival. Nevertheless, this model has some limitations and consequently further investigations should be performed to improve the organ allocation policy in liver transplantation.

Blood group O candidates remain on the waiting list for a liver transplant for a longer time than candidates of other blood groups. Herein, we analyzed potential factors affecting waiting times in the period that preceded the introduction of the model for end-stage liver disease (MELD) and in MELD era, remarking possible corrections introduced by the adoption of the MELD.

Our analysis was entirely based on data obtained from the "Organ Procurement and Transplantation Network", referring to the periods before and after the adoption of the MELD.

In the MELD era, taking into consideration all candidates, the cumulative probability of remaining on the waiting list significantly diminished whereas that of undergoing transplantation significantly increased when compared with the pre-MELD era. However, group O candidates maintained the lowest cumulative probability of undergoing liver transplant, in all MELD classes, and the highest percentage of list removal for death/too sick. What caused the highest disadvantage for group O, in both eras, was the use of group O organs for ABO-compatible transplants, even in the absence of urgency. In candidates receiving ABO-compatible organs a significantly lower graft survival rate was observed compared with candidates receiving ABO-identical organs, even when the analysis was adjusted for the MELD score.

The introduction of the MELD significantly reduced the waiting time for all candidates as also the shift of group O organs. Limiting ABO-compatible organs exclusively to urgent cases would have a positive effect not only in terms of individual justice, but also terms of in general utility, considering the effect of ABO-matching on graft survival.

The effect of patient travel time to a transplant center on outcomes is unknown. We compared outcomes between patients living >3 hours (Group A) vs. <or=3 (Group B) hours drive away. Adult, nonacute liver failure patients entering transplant evaluation from February 27, 2002 to January 31, 2005 were analyzed. Of 166 patients, 126 (75.5%) were listed and 66 (39.5%) received transplantation. Outcomes of interest were >90 days to list, listing, survival while listed, transplantation, and posttransplantation survival. Covariates included Model for End-Stage Liver Disease (MELD) score, hepatocellular carcinoma (HCC), alcoholic liver disease, insurance type, and psychosocial score. There were 38 (23%) patients in Group A and 128 (77%) in Group B. Median MELD scores were 14.5 (range, 6-36) for Group A and 14.0 (range, 7-32) for Group B (p = 0.20). Groups were similar for age, gender, diagnosis, psychosocial score, insurance, and HCC variables. Group A was not independently associated with >90 days to list (odds ratio, 0.98; 95% confidence interval [CI], 0.4-2.4). Kaplan-Meier cumulative probabilities for listing, transplantation, and 1-yr posttransplantation survival were similar (A vs. B: 0.77 vs. 0.83, 0.70 vs. 0.69, and 0.85 vs. 0.86, respectively; all p values >0.05). Being in Group A remained insignificant in terms of probability of listing, transplantation, and posttransplantation survival by Cox proportional hazard modeling. Survival on the list was significantly better for Group A (A: 1.0, B: 0.55; p = 0.02). Fewer patients at high MELD score in Group A and referral biases may explain this difference. In conclusion, after entering evaluation, patients living >3 hours away from a transplant center have comparable outcomes to those living closer.

The allocation of cadaveric organs for transplantation in the United States is governed by a process of private regulation. Through the Organ Procurement and Transplantation Network (OPTN), stakeholders and public representatives determine the substantive content of allocation rules. Between 1994 and 2000 the U.S. Department of Health and Human Services conducted a rule making to define more clearly the public and private roles in the determination of organ allocation policy. Several prominent liver transplant centers that were losing market share as a result of the proliferation of transplant centers used the rule making as a vehicle for challenging the local priority for organ allocation inherent in the OPTN rules. The process leading to the final rule provides a window on the politics of organ allocation. It also facilitates an assessment of the strengths and weaknesses of private rule making. Overall, private rule making appears to be relatively effective in tapping the technical expertise and tacit knowledge of stakeholders to allow for the adaptation of rules in the face of changing technology and information. However, the particular system of representation employed may give less influence to some stakeholders than they would have in public regulatory arenas, giving them an incentive to seek public rule making as a remedy for their persistent losses within the framework of private rule making.

As the number of pre- and post-transplant solid organ recipients continues to grow, it becomes important for all physicians to have an understanding of the process of organ procurement and allocation. In the United States, the current system for allocation and transplantation of human solid organs has been heavily influenced by the experience in deceased donor liver transplantation (DDLT). This review highlights the significant changes that have occurred over the past 10 years in DDLT, with specific attention to the impact of the Model for Endstage Liver Disease (MELD) score on organ allocation and pre- and post-transplant survival. DDLT is managed by the United Network for Organ Sharing (UNOS) which oversees organ procurement and allocation across geographically defined Organ Procurement Organizations (OPOs). For many years, deceased donor livers were allocated to waiting list patients based on subjective parameters of disease severity and accrued waiting time. In addition, organs have traditionally been retained within the OPO where they are procured contributing to geographic disparities in disease severity at the time of transplantation among deceased donor recipients. In response to a perceived unfairness in organ allocation, Congress issued its "Final Rule" in 1998. The Rule called for a more objective ranking of waiting list patients and more parity in disease severity among transplant recipients across OPOs. To date, little progress has been made in eliminating geographic inequities. Patients in the smallest OPOs continue to receive liver transplants at a lower level of disease severity. However, strides have been made to standardize assessments of disease severity and better prioritize waiting list patients. The MELD score has emerged as an excellent predictor of short-term mortality in patients with advanced liver disease, and patients listed for liver transplantation are now ranked based on their respective MELD scores. This has improved organ access to the most severely ill patients without compromising waiting list mortality or post-transplant survival. The current system for DDLT remains imperfect but has improved significantly in the past decade. As the number of patients in need of DDLT grows, the system will continue to evolve to meet this increasing demand.

A national conference was held to review and assess data gathered since implementation of MELD and PELD and determine future directions. The objectives of the conference were to review the current system of liver allocation with a critical analysis of its strengths and weaknesses. Conference participants used an evidence-based approach to consider whether predicted outcome after transplantation should influence allocation, to discuss the concept of minimal listing score, to revisit current and potential expansion of exception criteria, and to determine whether specific scores should be used for automatic removal of patients on the waiting list. After review of data from the first 18 months since implementation, association and society leaders, and surgeons and hepatologists with wide regional representation were invited to participate in small group discussions focusing on each of the main objectives. At the completion of the meeting, there was agreement that MELD has had a successful initial implementation, meeting the goal of providing a system of allocation that emphasizes the urgency of the candidate while diminishing the reliance on waiting time, and that it has proven to be a powerful tool for auditing the liver allocation system. It was also agreed that the data regarding the accuracy of PELD as a predictor of pretransplant mortality were less conclusive and that PELD should be considered in isolation. Recommendations for the transplant community, based on the analysis of the MELD data, were discussed and are presented in the summary document.

On February 27, 2002, the liver allocation system changed from a status-based algorithm to one using a continuous MELD/PELD severity score to prioritize patients on the waiting list. Using data from the Scientific Registry of Transplant Recipients, we examine and discuss several aspects of the new allocation, including the development and evolution of MELD and PELD, the relationship between the two scoring systems, and the resulting effect on access to transplantation and waiting list mortality. Additional considerations, such as regional differences in MELD/PELD at transplantation and the predictive effects of rapidly changing MELD/PELD, are also addressed. Death or removal from the waiting list for being too sick for a transplant has decreased in the MELD/PELD era for both children and adults. Children younger than 2 years, however, still have a considerably higher rate of death on the waiting list than adults. A limited definition of ECD livers suggests that they are used more frequently for patients with lower MELD scores.

The Etablissement français des Greffes reports regional variability in access to organ transplantation in France. Some variability seems to be inevitable for reasons discussed in the French article. We provide comparative data on a similar phenomenon in the United States, including some historical perspectives and recent attempts to minimize geographic variability especially for patients in urgent need of liver transplants.

To assess regional variability in access to heart, liver, and kidney transplants, a competing risks method was used. Outcomes were examined for primary transplant candidates added to the waiting list during 3-year periods. Results were stratified by region of listing.

Four months after listing, the transplant rate for all U.S. kidney transplant candidates was 10.9%. Regionally the 4-month transplant rate ranged from 4.2% to 18.5% for highly sensitized patients and from 5.4% to 19.6% for nonsensitized patients. For liver candidates, the overall national transplant rate 4 months after listing was 22%, but the overall regional rate varied from 11.8% to 36.5%. The overall transplant rate for heart candidates 4 months after listing was 43.9%, whereas regional 30-day transplant rates for the most urgent heart candidates (status 1A) ranged from 25.1% to 47.1%. Four-month transplant rates for less urgent heart candidates ranged from 24.9% to 40.7%.

Similar to the French experience, pretransplantation waiting times in the 11 U.S. regions vary considerably. Computer-simulated modeling shows that redrawing organ distribution boundaries could reduce but not eliminate geographic variability. It may be too early to tell whether the recently implemented Model for End-Stage Liver Disease/Pediatric End-Stage Liver Disease liver allocation system will decrease regional variability in access to transplant as compared with the previous system.