Geographic disparities in transplantation.

PURPOSE OF REVIEW: The Final Rule clearly states that geography should not be a determinant of a chance of a potential candidate being transplanted. There have been multiple concerns about geographic disparities in patients in need of solid organ transplantation. Allocation policy adjustments have been designed to address these concerns, but there is little evidence that the disparities have been solved. The purpose of this review is to describe the main drivers of geographic disparities in solid organ transplantation and how allocation policy changes and other potential actions could impact these inequalities. RECENT FINDINGS: Geographical disparities have been reported in kidney, pancreas, liver, and lung transplantation. Organ Procurement and Transplant Network has modified organ allocation rules to underplay geography as a key determinant of a candidates' chance of receiving an organ. Thus, heart, lung, and more recently liver and Kidney Allocation Systems have incorporated broader organ sharing to reduce geographical disparities. Whether these policy adjustments will indeed eliminate geographical disparities are still unclear. SUMMARY: Modern allocation policy focus in patients need, regardless of geography. Innovative actions to further reduce geographical disparities are needed.

Survival implications of prescription opioid and benzodiazepine use in lung transplant recipients: Analysis of linked transplant registry and pharmacy fill records.

BACKGROUND: Prescription opioid and benzodiazepine use have been associated with morbidity and mortality among some groups of solid organ transplant recipients, but implications for outcomes among lung transplant patients are not well described. METHODS: We conducted a retrospective cohort study using linked national transplant registry and pharmaceutical records to characterize the associations between benzodiazepine and opioid prescription fills in the years before and after lung transplant (2006-2017), with risk-adjusted posttransplant survival (adjusted hazard ratio, LCLaHRUCL). RESULTS: Among 11,568 recipients, 33.7% filled an opioid prescription, and 25.8% filled a benzodiazepine prescription before transplant. Compared to patients without prescriptions, those who filled both short- and long-acting benzodiazepine prescriptions before transplant had 2-fold higher mortality in the first year posttransplant (aHR, 1.392.123.21), after adjustment for baseline factors and opioid fills, while pretransplant opioid fills were not associated with posttransplant mortality after adjustment for benzodiazepine fills. Pretransplant opioid and benzodiazepine use strongly predicted more use after transplant. Fills of both short- and long-acting benzodiazepines in the first year posttransplant were associated with 77% increased mortality >1-to-2 years posttransplant (aHR, 1.061.772.96). Compared with no posttransplant opioid fills, there was a dose-dependent association between first-year opioid fills and subsequent adjusted mortality risk (level 2: aHR, 1.171.501.92 to level 4: aHR, 1.562.012.59). These effects were independent, and interactions were not detected. CONCLUSIONS: Benzodiazepine prescription fills before and after lung transplant, and opioid fills after transplant, are independently associated with posttransplant mortality. Review of benzodiazepine and opioid use history is relevant to risk-stratifying patients before and after lung transplant.

An International survey on living kidney donation and transplant practices during the COVID-19 pandemic.

The scope of the impact of the Coronavirus disease 19 (COVID-19) pandemic on living donor kidney transplantation (LDKT) practices across the world is not well-defined. We received survey responses from 204 transplant centers internationally from May to June 2020 regarding the impact of the COVID-19 pandemic on LDKT practices. Respondents represented 16 countries on five continents. Overall, 75% of responding centers reported that LDKT surgery was on hold (from 67% of North American centers to 91% of European centers). The majority (59%) of centers reported that new donor evaluations were stopped (from 46% of North American centers to 86% of European centers), with additional 23% of centers reporting important decrease in evaluations. Only 10% of centers reported slight variations on their evaluations. For the centers that continued donor evaluations, 40% performed in-person visits, 68% by video, and 42% by telephone. Center concerns for donor (82%) and recipient (76%) safety were the leading barriers to LDKT during the pandemic, followed by patients concerns (48%), and government restrictions (46%). European centers reported more barriers related to staff limitations while North and Latin American centers were more concerned with testing capacity and insufficient resources including protective equipment. As LDKT resumes, 96% of the programs intend to screen donor and recipient pairs for coronavirus infection, most of them with polymerase chain reaction testing of nasopharyngeal swab samples. The COVID-19 pandemic has had broad impact on all aspects of LDKT practice. Ongoing research and consensus-building are needed to guide safe reopening of LDKT programs.

Recovery of the Cholangiocytes After Ischemia and Reperfusion Injury: Ultra-Structural, Hystological and Molecular Assessment in Rats.

INTRODUCTION: Ischemia-reperfusion (I/R) injury of the liver is a common area of interest to transplant and hepatic surgery. Nevertheless, most of the current knowledge of I/R of the liver derives from the hepatocyte and little is known of what happens to the cholangiocytes. Herein, we assess the sequence of early events involved in the I/R injury of the cholangiocytes. METHODS: Sixty Wistar rats were randomized in a SHAM group and I/R group. Serum biochemistry, histopathology, immunohistochemistry, transmission electron microscopy (TEM) and laser capture microdissection (LCM) were used for group comparison. RESULTS: There was peak of alkaline phosphatase 24 h after IR injury, and an increase of aspartate aminotransferase and alanine aminotransferase after 6 h of reperfusion, followed by a return to normal levels 24 h after injury. The I/R group presented the liver parenchyma with hepatocellular degeneration up to 6 h, followed by hepatocellular necrosis at 24 h. TEM showed cholangiocyte injury, including a progressive nuclear degeneration and cell membrane rupture, beginning at 6 h and peaking at 24 h after reperfusion. Cytokeratin-18 and caspase-3-positive areas were observed in the I/R group, peaking at 24-h reperfusion. Anti-apoptotic genes Bcl-2 and Bcl-xl activity were expressed from 6 through 24 h after reperfusion. BAX expression showed an increase for 24 h. CONCLUSIONS: I/R injury to the cholangiocyte occurs from 6 through 24 h after reperfusion and a combination of TEM, immunohistochemistry and LCM allows a better isolation of the cholangiocyte and a proper investigation of the events related to the I/R injury. Apoptosis is certainly involved in the I/R process, particularly mediated by BAX.

Impact of continuous training through distributed practice for acquisition of minimally invasive surgical skills.

BACKGROUND: Minimally invasive surgery (MIS) requires the mastery of manual skills and a specific training is required. Apart from residencies and fellowships in MIS, other learning opportunities utilize massive training, mainly with use of simulators in short courses. A long-term postgraduate course represents an opportunity to learn through training using distributed practice. OBJECTIVE: The objective of this study is to assess the use of distributed practice for acquisition of basic minimally invasive skills in surgeons who participated in a long-term MIS postgraduate course. METHODS: A prospective, longitudinal and quantitative study was conducted among surgeons who attended a 1-year postgraduate course of MIS in Brazil, from 2012 to 2014. They were tested through five different exercises in box trainers (peg-transfer, passing, cutting, intracorporeal knot, and suture) in the first (t0), fourth (t1) and last, eighth, (t2) meetings of this course. The time and penalties of each exercise were collected for each participant. Participant skills were assessed based on time and accuracy on a previously tested score. RESULTS: Fifty-seven surgeons (participants) from three consecutive groups participated in this study. There was a significant improvement in scores in all exercises. The average increase in scores between t0 and t2 was 88% for peg-transfer, 174% for passing, 149% for cutting, 130% for intracorporeal knot, and 120% for suture (p < 0.001 for all exercises). CONCLUSION: Learning through distributed practice is effective and should be integrated into a MIS postgraduate course curriculum for acquisition of core skills.

Retention of laparoscopic skills in naive medical students who underwent short training.

BACKGROUND: Simulators are useful tools in the development of laparoscopic skills. However, little is known about the effectiveness of short laparoscopic training sessions and how retention of skills occurs in surgical trainees who are naïve to laparoscopy. This study analyses the retention of laparoscopic surgical skills in medical students without prior surgical training. METHODS: A group of first- and second-year medical students (n = 68), without prior experience in surgery or laparoscopy, answered a demographic questionnaire and had their laparoscopic skills assessed by the Fundamentals of Laparoscopic Surgery (FLS) training protocol. Subsequently, they underwent a 150-minute training course after which they were re-tested. One year after the training, the medical students' performance in the simulator was re-evaluated in order to analyse retention. RESULTS: Of the initial 68 students, a total of 36 participated throughout the entire study, giving a final participation rate of 52 %. Thirty-six medical students with no gender predominance and an average age of 20 years were evaluated. One year after the short training programme, retention was 69.3 % in the peg transfer (p < 0.05) and 64.2 % in ligature (p < 0.05) compared with immediate post-training evaluation. There was no significant difference in suturing. The average sample score in the baseline test was 8.3, in the post-training test it was 89.7, and in the retention test it was 84.2, which corresponded to a skill retention equivalence of 93 %. CONCLUSIONS: There was a significant retention of the laparoscopic surgical skills developed. Even 1 year after a short training session, medical students without previous surgical experience showed that they have retained a great part of the skills acquired through training.

Consensus, Dilemmas, and Challenges in Living Donor Liver Transplantation in Latin America.

We reviewed the history, volume, outcomes, uniqueness, and challenges of living donor liver transplantation (LDLT) in Latin America. We used the data from the Latin American and Caribbean Transplant Society, local transplant societies, and opinions from local transplant experts. There are more than 160 active liver transplant teams in Latin America, but only 30 centers have used LDLT in the past 2 years. In 2014, 226 LDLTs were done in the region (8.5% of liver transplant activities). Living donor liver transplantation is mainly restricted to pediatric patients. Adult-to-adult LDLT activities decreased after the implementation of the model for end-stage liver disease score and a concomitant increase on the rate of deceased donors per million population. Posttransplant outcome analysis is not mandatory, transparent or regulated in most countries. More experienced teams have outcomes comparable to international expert centers, but donor and recipient morbidity might be underreported. Latin America lags behind in terms of the number of adult LDLT and the rate of living donor utilization in comparison with other continents with similar donation rates. Local alliances and collaborations with major transplant centers in the developed world will contribute to the development of LDLT in Latin America.

Liver transplantation in Latin America: the state-of-the-art and future trends.

We reviewed the current status of liver transplantation in Latin America. We used data from the Latin American and Caribbean Transplant Society and national organizations and societies, as well as information obtained from local transplant leaders. Latin America has a population of 589 million (8.5% of world population) and more than 2,500 liver transplantations are performed yearly (17% of world activity), resulting in 4.4 liver transplants per million people (pmp) per year. The number of liver transplantations grows at 6% per year in the region, particularly in Brazil. The top liver transplant rates were found in Argentina (10.4 pmp), Brazil (8.4 pmp), and Uruguay (5.5 pmp). The state of liver transplantation in some countries rivals those in developed countries. Model for End-Stage Liver Disease-based allocation, split, domino, and living-donor adult and pediatric transplantations are now routinely performed with outcomes comparable to those in advanced economies. In contrast, liver transplantation is not performed in 35% of Latin American countries and lags adequate resources in many others. The lack of adequate financial coverage, education, and organization is still the main limiting factor in the development of liver transplantation in Latin America. The liver transplant community in the region should push health care leaders and authorities to comply with the Madrid and Istambul resolutions on organ donation and transplantation. It must pursue fiercely the development of registries to advance the science and quality control of liver transplant activities in Latin America.

Hepatocellular carcinomas within the Milan criteria: predictors of histologic necrosis after drug-eluting beads transarterial chemoembolization.

PURPOSE: To evaluate pathologic, imaging, and technical predictors of therapy response in patients with hepatocellular carcinoma (HCC) within the Milan criteria undergoing doxorubicin drug-eluting beads transarterial chemoembolization (DEB-TACE) before orthotopic liver transplantation (OLT). METHODS: This prospective study included consecutive patients with HCC who underwent DEB-TACE before OLT. Tumor histologic necrosis on liver explants was utilized as the standard of reference to categorize treated HCCs as group 1 (>50 % necrosis) or group 2 (≤50 % necrosis). DEB-TACE technique, histological factors, and imaging evaluation utilizing the modified Response Evaluation Criteria in Solid Tumors (mRECIST) were compared between groups 1 and 2. RESULTS: Twenty-seven HCCs were identified in 23 patients. Group 1 comprised 18 HCCs (mean necrosis 86.2 %). Group 2 comprised 9 HCCs (mean necrosis 31.1 %). The mean time between the last DEB-TACE session and the OLT was 112 days. Lesion size was significantly larger in group 1 (mean 3.2 cm; 95 % confidence interval 2.55-3.85) than in group 2 (mean 2.1 cm; 95 % confidence interval 1.79-2.48) (p = 0.030). Group 1 also demonstrated a higher frequency of encapsulated lesions when compared to group 2 (78 % vs. 22 %; p = 0.0027). A significant linear correlation was found between the quantification of necrosis by imaging and pathology (p = 0.0011) using the mRECIST, with a poorer correlation index in group 2. CONCLUSION: Larger and encapsulated HCCS are associated with a higher percentage of necrosis. A significant linear correlation between the amount of necrosis by imaging and pathology was encountered when mRECIST was utilized.

Predicting long-term graft survival in adult kidney transplant recipients.

The ability to accurately predict a population's long-term survival has important implications for quantifying the benefits of transplantation. To identify a model that can accurately predict a kidney transplant population's long-term graft survival, we retrospectively studied the United Network of Organ Sharing data from 13,111 kidney-only transplants completed in 1988- 1989. Nineteen-year death-censored graft survival (DCGS) projections were calculated and compared with the population's actual graft survival. The projection curves were created using a two-part estimation model that (1) fits a Kaplan-Meier survival curve immediately after transplant (Part A) and (2) uses truncated observational data to model a survival function for long-term projection (Part B). Projection curves were examined using varying amounts of time to fit both parts of the model. The accuracy of the projection curve was determined by examining whether predicted survival fell within the 95% confidence interval for the 19-year Kaplan-Meier survival, and the sample size needed to detect the difference in projected versus observed survival in a clinical trial. The 19-year DCGS was 40.7% (39.8-41.6%). Excellent predictability (41.3%) can be achieved when Part A is fit for three years and Part B is projected using two additional years of data. Using less than five total years of data tended to overestimate the population's long-term survival, accurate prediction of long-term DCGS is possible, but requires attention to the quantity data used in the projection method.

The clinical and financial burden of early dialysis after deceased donor kidney transplantation.

BACKGROUND: The economic implications of dialysis-requiring allograft dysfunction early after kidney transplantation are not well-described. METHODS: Data for Medicare-insured adult kidney transplant recipients in 1995-2004 who did not develop permanent graft failure in the first 90 days were drawn from the United States Renal Data System. We identified dialysis treatment records from Medicare claims and categorized patients according to frequency and duration of post-transplant dialysis as: first week (delayed graft function, DGF), second week, weeks 3 or 4, second month, or third month. Associations of dialysis requirements with Medicare payments for the transplant hospitalization and over the next three years were estimated with multivariable linear regression. Graft and patient survival according to early dialysis requirements were examined with multivariable survival analysis. RESULTS: Among 37,533 recipients, 15,314 (41%) experienced DGF and 3,184 (21% of those with DGF) received dialysis beyond the first week. Compared with no dialysis in the first 3 months, adjusted marginal first-year costs associated with early post-transplant dialysis ranged from $6,467 for dialysis requirement limited to first week to $27,606 for dialysis in multiple periods (p<0.0001). Patients who experienced DGF and received dialysis in >2 early periods were more than twice as likely to lose their grafts within 3 years as those without early dialysis requirements. CONCLUSIONS: While dialysis in the first week post-transplant is an adverse risk marker, early dialysis in weeks 2 to 12 is associated with similarly adverse, if not worse, costs and clinical consequences. This observation supports a need for broader definition of DGF.

Associations of recipient illness history with hypertension and diabetes after living kidney donation.

BACKGROUND: Little is known about associations of family health history with outcomes after kidney donation. METHODS: Using a database wherein Organ Procurement and Transplantation Network identifiers for 4650 living kidney donors in 1987 to 2007 were linked to administrative data of a US private health insurer (2000-2007 claims), we examined associations of recipient illness history as a measure of family history with postdonation diagnoses and drug-treatment for hypertension and diabetes. Cox regression with left and right censoring was applied to estimate associations (adjusted hazards ratios, aHR) of recipient illness history with postnephrectomy donor diagnoses, stratified by donor-recipient relationship. RESULTS: Recipient end-stage renal disease from hypertension, as compared with other recipient end-stage renal disease causes, was associated with modest, significant increases in the age- and gender-adjusted relative risks of hypertension diagnosis (aHR, 1.37%; 95% confidence interval [CI], 1.08-1.74) after donor nephrectomy among related donors. After adjustment for age, gender, and race, recipient type 2 diabetes compared with non-diabetic recipient status was associated with twice the relative risk of postdonation diabetes (aHR, 2.14; 95% CI, 1.28-3.55; P=0.003) among related donors. These patterns were significant among white but not among non-white related donors. Recipient type 1 diabetes was associated with postdonation diabetes only in black related donors (aHR, 3.22; 95% CI, 1.04-9.98; P=0.04). Recipient illness did not correlate significantly with outcomes in unrelated donors. CONCLUSIONS: These data support a need for further study of family health history as a potential sociodemographic correlate of donor outcomes, including examination of potential mediating factors and variation in risk discrimination among donors of different racial groups.

The interaction among donor characteristics, severity of liver disease, and the cost of liver transplantation.

Accurate assessment of the impact of donor quality on liver transplant (LT) costs has been limited by the lack of a large, multicenter study of detailed clinical and economic data. A novel, retrospective database linking information from the University HealthSystem Consortium and the Organ Procurement and Transplantation Network registry was analyzed using multivariate regression to determine the relationship between donor quality (assessed through the Donor Risk Index [DRI]), recipient illness severity, and total inpatient costs (transplant and all readmissions) for 1 year following LT. Cost data were available for 9059 LT recipients. Increasing MELD score, higher DRI, simultaneous liver-kidney transplant, female sex, and prior liver transplant were associated with increasing cost of LT (P < 0.05). MELD and DRI interact to synergistically increase the cost of LT (P < 0.05). Donors in the highest DRI quartile added close to $12,000 to the cost of transplantation and nearly $22,000 to posttransplant costs in comparison to the lowest risk donors. Among the individual components of the DRI, donation after cardiac death (increased costs by $20,769 versus brain dead donors) had the greatest impact on transplant costs. Overall, 1-year costs were increased in older donors, minority donors, nationally shared organs, and those with cold ischemic times of 7-13 hours (P < 0.05 for all). In conclusion, donor quality, as measured by the DRI, is an independent predictor of LT costs in the perioperative and postoperative periods. Centers in highly competitive regions that perform transplantation on higher MELD patients with high DRI livers may be particularly affected by the synergistic impact of these factors.

Three-year post-transplant Medicare payments in kidney transplant recipients: associations with pre-transplant comorbidities.

Little is known about the influence of pre-transplant comorbidities on post-transplant expenditures. We estimated the associations between pre-transplant comorbidities and post-transplant Medicare costs, using several comorbidity classification systems. We included recipients of first-kidney deceased donor transplants from 1995 through 2002 for whom Medicare was the primary payer for at least one year pre-transplant (N = 25,175). We examined pre-transplant comorbidities as classified by International Classification of Diseases (ICD-9-CM) codes from Medicare claims with the Clinical Classifications Software (CCS) and Charlson and Elixhauser algorithms. Post-transplant costs were calculated from payments on Medicare claims. We developed models considering Organ Procurement and Transplantation Network (OPTN) variables plus: 1) CCS categories, 2) Charlson, 3) Elixhauser, 4) number of Charlson and 5) number of Elixhauser comorbidities, independently. We applied a novel regression methodology to account for censoring. Costs were estimated at individual and population levels. The comorbidities with the largest impact on mean Medicare payments included cardiovascular disease, malignancies, cerebrovascular disease, mental conditions and functional limitations. Skin ulcers and infections, rheumatic and other connective tissue disease and liver disease also contributed to payments and have not been considered or described previously. A positive graded relationship was found between costs and the number of pre-transplant comorbidities. In conclusion, we showed that expansion beyond the usually considered pre-transplant comorbidities with inclusion of CCS and Charlson or Elixhauser comorbidities increased the knowledge about comorbidities related to augmented Medicare payments. Our expanded methodology can be used by others to assess more accurately the financial implications of renal transplantation to Medicare and individual transplant centers.

Regional differences in deceased donor liver transplantation and their implications for organ utilization and allocation.

We examined the UNOS database from 7/15/00-7/17/05 for Regional deceased donor liver utilization. For each region, we performed logistic regression and derived odds ratios (OR) for donor characteristics associated with livers being transplanted outside of the region or not transplanted at all. Regions with smallest and least significant OR were considered aggressive users of suboptimal organs. We estimated how many untransplanted livers from less aggressive regions might be used by more aggressive regions. Only Region 9 was significantly more aggressive than others (median OR: 6 vs. 16; p < 0.01; median OR size: 1.4 vs. 3.6; p < 0.01). Region 9 transplanted at higher median Model for End-stage Liver Disease (MELD) score (20.4 [6-73] vs. 18.3 [6-70], p < 0.01), but had the lowest one- and five-yr graft survival (p < 0.01). Of 30,474 livers, 5056 were not transplanted, of which 3690 were procured outside Region 9 but met Region 9 use criteria. Of these, 1488 and 1807 livers had donor risk indices ≤ 2, for hypothetical 12 and 8 h cold ischemia time (CIT), respectively. Regional differences in liver utilization are profound. Region 9 is significantly more aggressive. At the most, 297-361 organs per year may have been used under Region 9's use criteria but overall graft survival may have declined.

Kidney transplant Medicare payments and length of stay: associations with comorbidities and organ quality.

INTRODUCTION: We investigated associations between pre-transplant comorbidities, length of stay (LOS) and Medicare payments for transplant hospitalization. MATERIAL AND METHODS: We examined United States Renal Data System for 24,963 recipients of first deceased-donor kidney transplants in 1995-2002 for whom Medicare was the primary payer for at least a year pre-transplant. Pre-transplant ICD-9-CM codes from claims were classified with the Charlson and Elixhauser algorithms. Regression models for payments and LOS included: 1) baseline recipient, donor and transplant factors from the Organ Procurement and Transplant Network (OPTN), 2) OPTN variables and individual comorbidities and 3) OPTN variables and counts of Charlson or Elixhauser comorbidities. RESULTS: Factors most strongly associated with LOS were type I diabetes, cold ischemia time > 36 h, expanded criteria donor (ECD) and donation after cardiac death (DCD). Except for ECD, each was associated with increased payments. Upper respiratory disease, liver disease, peptic ulcer disease, diabetes, cancer and other diseases were also associated with increased LOS and payments. Each additional Charlson comorbidity increased LOS by 2.94% and payments by $471 (Elixhauser results: 1.71% for LOS, $277 for payments). Use of ECD or DCD organs were associated with 10-15% higher LOS and 5% increased Medicare payments for DCD. CONCLUSIONS: This methodology could be used to explore if Medicare reimbursement for transplantation of higher-risk recipients and using non-standard organs is financially adequate and to analyze related questions in other healthcare systems.

Racial variation in medical outcomes among living kidney donors.

BACKGROUND: Data regarding health outcomes among living kidney donors are lacking, especially among nonwhite persons. METHODS: We linked identifiers from the Organ Procurement and Transplantation Network (OPTN) with administrative data of a private U.S. health insurer and performed a retrospective study of 4650 persons who had been living kidney donors from October 1987 through July 2007 and who had post-donation nephrectomy benefits with this insurer at some point from 2000 through 2007. We ascertained post-nephrectomy medical diagnoses and conditions requiring medical treatment from billing claims. Cox regression analyses with left and right censoring to account for observed periods of insurance benefits were used to estimate absolute prevalence and prevalence ratios for diagnoses after nephrectomy. We then compared prevalence patterns with those in the 2005-2006 National Health and Nutrition Examination Survey (NHANES) for the general population. RESULTS: Among the donors, 76.3% were white, 13.1% black, 8.2% Hispanic, and 2.4% another race or ethnic group. The median time from donation to the end of insurance benefits was 7.7 years. After kidney donation, black donors, as compared with white donors, had an increased risk of hypertension (adjusted hazard ratio, 1.52; 95% confidence interval [CI], 1.23 to 1.88), diabetes mellitus requiring drug therapy (adjusted hazard ratio, 2.31; 95% CI, 1.33 to 3.98), and chronic kidney disease (adjusted hazard ratio, 2.32; 95% CI, 1.48 to 3.62); findings were similar for Hispanic donors. The absolute prevalence of diabetes among all donors did not exceed that in the general population, but the prevalence of hypertension exceeded NHANES estimates in some subgroups. End-stage renal disease was identified in less than 1% of donors but was more common among black donors than among white donors. CONCLUSIONS: As in the general U.S. population, racial disparities in medical conditions occur among living kidney donors. Increased attention to health outcomes among demographically diverse kidney donors is needed. (Funded by the National Institute of Diabetes and Digestive and Kidney Diseases and others.)

The interplay of socioeconomic status, distance to center, and interdonor service area travel on kidney transplant access and outcomes.

BACKGROUND AND OBJECTIVES: Variation in kidney transplant access across the United States may motivate relocation of patients with ability to travel to better-supplied areas. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: We examined national transplant registry and U.S. Census data for kidney transplant candidates listed in 1999 to 2009 with a reported residential zip code (n = 203,267). Cox's regression was used to assess associations of socioeconomic status (SES), distance from residence to transplant center, and relocation to a different donation service area (DSA) with transplant access and outcomes. RESULTS: Patients in the highest SES quartile had increased access to transplant compared with those with lowest SES, driven strongly by 76% higher likelihood of living donor transplantation (adjusted hazard ratio [aHR] 1.76, 95% confidence interval [CI] 1.70 to 1.83). Waitlist death was reduced in high compared with low SES candidates (aHR 0.86, 95% CI 0.84 to 0.89). High SES patients also experienced lower mortality after living and deceased donor transplant. Patients living farther from the transplant center had reduced access to deceased donor transplant and increased risk of post-transplant death. Inter-DSA travel was associated with a dramatic increase in deceased donor transplant access (HR 1.94, 95% CI 1.88 to 2.00) and was predicted by high SES, white race, and longer deceased-donor allograft waiting time in initial DSA. CONCLUSIONS: Ongoing disparities exist in kidney transplantation access and outcomes on the basis of geography and SES despite near-universal insurance coverage under Medicare. Inter-DSA travel improves access and is more common among high SES candidates.

Intraoperative portal vein blood flow predicts allograft and patient survival following liver transplantation.

BACKGROUND: We hypothesized that operative variables might predict survival following liver transplantation. METHODS: We examined perioperative variables from 469 liver transplants carried out at the University of Washington during 2003-2006. Logistic regression determined the variables' contributions to survival at 30, 90 and 365 days. RESULTS: Portal vein blood flow (>1 l/min) was significant to patient survival at 30, 90 and 365 days. Complete reperfusion was only a significant predictor of survival at 30 days. This provided model receiver operating characteristic (ROC) area under the curve (AUC) statistics of 0.93 and 0.87 for 30 and 90 days, respectively. At 365 days, hepatic artery blood flow (>250 ml/min) combined with portal vein blood flow was significantly predictive of survival, with an AUC of 0.74. A subset analysis of 110 transplants demonstrated improved 1-year survival with more aggressive vascular revisions. DISCUSSION: Portal vein blood flow is a significant predictor of survival after liver transplantation. Initially, the liver's survival is based on portal vein blood flow; however, subsequent biliary problems and patient demise result from both poor portal vein and inadequate hepatic artery blood flow.