Center-related Bias in MELD Scores Within a Liver Transplant UNOS Region: A Call for Standardization.

BACKGROUND: Model for End-Stage Liver Disease (MELD) score-based liver transplant allocation was implemented as a fair and objective measure to prioritize patients based upon disease severity. Accuracy and reproducibility of MELD is an essential assumption to ensure fairness in organ access. We hypothesized that variability in laboratory methodology between centers could impact allocation scores for individuals on the transplant waiting list. METHODS: Aliquots of 30 patient serum samples were analyzed for creatinine, bilirubin, and sodium in all transplant centers within United Network for Organ Sharing (UNOS) region 9. Descriptive statistics, intraclass correlation coefficients (ICCs), and linear mixed-effects regression were used to determine the relationship between center, bilirubin, and calculated MELD-sodium (MELD-Na) score. RESULTS: The mean MELD-Na score per sample ranged from 14 to 38. The mean range in MELD-Na per sample was 3 points, but 30% of samples had a range of 4-6 points. Correlation plots and intraclass correlation coefficient analysis confirmed bilirubin interfered with creatinine, with worsening agreement in creatinine at high bilirubin levels. Center and bilirubin were independently associated with creatinine reported in mixed-effects models. Unbiased hierarchical clustering suggested that samples from specific centers have consistently higher creatinine and MELD-Na values. CONCLUSIONS: Despite implementation of creatinine standardization, centers within a single UNOS region report clinically significant differences in MELD-Na on an identical sample, with differences of up to 6 points in high MELD-Na patients. The bias in MELD-Na scores based upon center choice within a region should be addressed in the current efforts to eliminate disparities in liver transplant access.

Addition of adult-to-adult living donation to liver transplant programs improves survival but at an increased cost.

Using outcomes data from the Adult-to-Adult Living Donor Liver Transplantation Cohort Study, we performed a cost-effectiveness analysis exploring the costs and benefits of living donor liver transplantation (LDLT). A multistage Markov decision analysis model was developed with treatment, including medical management only (strategy 1), waiting list with possible deceased donor liver transplantation (DDLT; strategy 2), and waiting list with possible LDLT or DDLT (strategy 3) over 10 years. Decompensated cirrhosis with medical management offered survival of 2.0 quality-adjusted life years (QALYs) while costing an average of $65,068, waiting list with possible DDLT offered 4.4-QALY survival and a mean cost of $151,613, and waiting list with possible DDLT or LDLT offered 4.9-QALY survival and a mean cost of $208,149. Strategy 2 had an incremental cost-effectiveness ratio (ICER) of $35,976 over strategy 1, whereas strategy 3 produced an ICER of $106,788 over strategy 2. On average, strategy 3 cost $47,693 more per QALY than strategy 1. Both DDLT and LDLT were cost-effective compared to medical management of cirrhosis over our 10-year study period. The addition of LDLT to a standard waiting list DDLT program is effective at improving recipient survival and preventing waiting list deaths but at a greater cost.

Donor morbidity after living donation for liver transplantation.

BACKGROUND & AIMS: Reports of complications among adult right hepatic lobe donors have been limited to single centers. The rate and severity of complications in living donors were investigated in the 9-center Adult-to-Adult Living Donor Liver Transplantation Cohort Study (A2ALL). METHODS: A retrospective observational study design was used. Participants included all potential living donors evaluated between 1998 and 2003. Complication severity was graded using the Clavien scoring system. RESULTS: Of 405 donors accepted for donation, 393 underwent donation, and 12 procedures were aborted. There were 245 donors (62%) who did not experience complications; 82 (21%) had 1 complication, and 66 (17%) had 2 or more. Complications were scored as grade 1 (minor; n = 106, 27%), grade 2 (potentially life threatening; n = 103, 26%), grade 3 (life threatening; n = 8, 2%), and grade 4 (leading to death; n = 3, 0.8%). Common complications included biliary leaks beyond postoperative day 7 (n = 36, 9%), bacterial infections (n = 49, 12%), incisional hernia (n = 22, 6%), pleural effusion requiring intervention (n = 21, 5%), neuropraxia (n = 16, 4%), reexploration (n = 12, 3%), wound infections (n = 12, 3%), and intraabdominal abscess (n = 9, 2%). Two donors developed portal vein thrombosis, and 1 had inferior vena caval thrombosis. Fifty-one (13%) donors required hospital readmission, and 14 (4%) required 2 to 5 readmissions. CONCLUSIONS: Adult living liver donation was associated with significant donor complications. Although most complications were of low-grade severity, a significant proportion were severe or life threatening. Quantification of complication risk may improve the informed consent process, perioperative planning, and donor care.

Predictors of candidate maturation among potential living donors.

The shortage of deceased donor allografts and improved outcomes in partial organ transplantation have led to widespread application of adult-to-adult living donor liver transplantation. Donor selection limits overall utilization of this technique and predictors of candidate maturation have been inadequately studied to date. We therefore collected data on 237 consecutive potential donors including their age, sex, ethnicity, relationship to the recipient, education, employment and religious beliefs and practices. Of these 237 candidates, 91 (38%) were excluded for medical and psychosocial reasons, 53 (22%) withdrew from the process predonation and 93 (39%) underwent partial liver donation. In multivariate analyses, the relationship between the donor and the recipient was highly predictive of successful donation. For pediatric recipients, no parents voluntarily withdrew from the evaluation process. For adult recipients, spouses are the most likely to donate, followed by parents, children and siblings. Additional predictors for donation included self-description as religious but not regularly practicing, part-time employment and higher education. Race, ethnicity, gender and age did not predict donation in multivariate analysis. Further understanding of the complex decision to donate may improve donation rates as well as permit more efficient and cost-effective donor evaluation strategies.

Utilization of extended donor criteria liver allografts maximizes donor use and patient access to liver transplantation.

OBJECTIVE: The objective of this study was to evaluate the effect of systematic utilization of extended donor criteria liver allografts (EDC), including living donor allografts (LDLT), on patient access to liver transplantation (LTX). SUMMARY BACKGROUND DATA: Utilization of liver allografts that do not meet traditional donor criteria (EDC) offer immediate expansion of the donor pool. EDC are typically allocated by transplant center rather than regional wait-list priority (RA). This single-institution series compares outcomes of EDC and RA allocation to determine the impact of EDC utilization on donor use and patient access to LTX. METHODS: The authors conducted a retrospective analysis of 99 EDC recipients (49 deceased donor, 50 LDLT) and 116 RA recipients from April 2001 through April 2004. Deceased-donor EDC included: age >65 years, donation after cardiac death, positive viral serology (hepatitis C, hepatitis B core antibody, human T-cell lymphotrophic), split-liver, hypernatremia, prior carcinoma, steatosis, and behavioral high-risk donors. Outcome variables included patient and graft survival, hospitalization, initial graft function, and complication categorized as: biliary, vascular, wound, and other. RESULTS: EDC recipients were more frequently diagnosed with hepatitis C virus or hepatocellular carcinoma and had a lower model for end-stage liver disease (MELD) score at LTX (P < 0.01). Wait-time, technical complications, and hospitalization were comparable. Log-rank analysis of Kaplan-Meier survival estimates demonstrated no difference in patient or graft survival; however, deaths among deceased-donor EDC recipients were frequently the result of patient comorbidities, whereas LDLT and RA deaths resulted from graft failure (P < 0.01). EDC increased patient access to LTX by 77% and reduced pre-LTX mortality by over 50% compared with regional data (P < 0.01). CONCLUSION: Systematic EDC utilization maximizes donor use, increases access to LTX, and significantly reduces wait-list mortality by providing satisfactory outcomes to select recipients.

Optimizing the use of donated cadaver livers: analysis and policy development to increase the application of split-liver transplantation.

The American Society of Transplant Surgeons and the American Society of Transplantation jointly sponsored a conference in Crystal City, Virginia, on March 28th and 29th, 2001, to explore mechanisms for maximizing the cadaver-organ donor pool. Participants from transplantation medicine, surgery, organ procurement organizations, the general public, and government convened to address expanding utilization of each organ type. The committee assigned to review liver organ utilization identified multiple practices that could expand the potential donor pool including non-heart beating donors, marginal grafts, efficient allocation of cadaver organs, and wider application of split-liver transplantation. This article details the data reviewed by the liver committee and their recommendations on policy development for the expanded application of split-liver transplantation.

Donor health assessment after living-donor liver transplantation.

OBJECTIVE: To elicit donor opinions on liver living donation through use of a survey that protected the anonymity of the respondent and to assay long-term (follow-up > 1 year) donor health by a widely recognized instrument for health assessment. SUMMARY BACKGROUND DATA: Living-donor liver transplantation is an accepted technique for children that has recently been extended to adults. Limited donor outcomes data suggest favorable results, but no outcomes data have been reported using an instrument that elicits an anonymous response from the donor or employs a widely recognized health survey. METHODS: Forty-one living-donors between June 1992 and June 1999 were identified and included in this study, regardless of specific donor or recipient outcome. Each donor received a 68-question survey and a standard McMaster Health Index. RESULTS: Survey response was 80%. All donors were satisfied with the information provided to them before donation. Eighty-eight percent of donors initially learned of living donation only after their child had been diagnosed with liver disease: 44% through the transplant center, 40% by popular media, 12% by their pediatrician, and 4% by their primary care physician. Physical symptoms, including pain and the surgical wound, were recurrent items of concern. Perception of time to "complete" recovery were less than 3 months (74%), 3 to 6 months (16%), and more than 6 months (10%). Donors' return to physical activities was shown by above-mean McMaster physical scores; scores for social and emotional health were not different from population data. There were no reported changes in sexual function or menstruation after donation, and five of six donors procreated. CONCLUSIONS: Donors overwhelmingly endorsed living donation regardless of recipient outcome or the occurrence of a complication. Eighty-nine percent advocated "increased" application of living donation beyond "emergency situations," and no donor responded that living donation should be abandoned or that he or she felt "forced" to donate.