Utilizing a novel MRI technique to identify adverse muscle composition in end-stage liver disease: A pilot study.

INTRODUCTION AND OBJECTIVES: Sarcopenia is a common complication of end-stage liver disease (ESLD), but its exact relationship to myosteatosis and frailty remains unclear. In this pilot study, we tested the feasibility of a specialized MRI protocol and automated image analysis in patients with ESLD. MATERIALS AND METHODS: In a single-center prospective study, adult liver transplant candidates with ESLD underwent assessment of muscle composition between 3/2022 and 6/2022 using the AMRA® MAsS Scan. The primary outcome of interest was feasibility of the novel MRI technique in patients with ESLD. We also tested if thigh muscle composition correlated with validated measures of frailty and sarcopenia. RESULTS: Eighteen subjects (71 % male, mean age 59 years) were enrolled. The most common etiologies of cirrhosis were alcohol-related liver disease (44 %) and non-alcohol-associated fatty liver disease (33 %), with a mean MELD-Na of 13 (± 4). The mean time needed to complete the MRI protocol was 14.9 min and only one patient could not complete it due to metal hardware in both knees. Forty-one percent of patients had adverse muscle composition (high thigh fat infiltration and low-fat free muscle volume) and these patients were more likely to have undergone a recent large volume paracentesis (43% vs. 0 %, p < 0.02). The adverse muscle composition group performed significantly worse on the 6-minute walk test compared to the remainder of the cohort (379 vs 470 m, p < 0.01). CONCLUSIONS: The AMRA® MAsS Scan is feasible to perform in patients with ESLD and can be used to quantify myosteatosis, a marker of muscle quality and potentially muscle functionality in ESLD.

Kidney transplant in pediatric gut transplant recipients - Technical challenges and outcomes.

BACKGROUND: There is limited data in the literature about pediatric kidney transplant (KT) following gut transplant (GT). The purpose of this study is to highlight the technical challenges and outcomes of KT in pediatric gut recipients who developed kidney failure (KF). METHODS: A retrospective single-center study of pediatric GT recipients from January 2000 to December 2019 was performed. In total, 14 (7%) out of 206 pediatric GT recipients developed KF and were listed for KT. Ten patients underwent kidney after gut transplant (KAGT), three patients underwent simultaneous kidney and re-do gut transplant (SKAGT), and one patient died on the KT waitlist. RESULTS: 1-, 5-, and 10-year kidney graft survival was 100%, 91%, and 78%, respectively. 1-, 5-, and 10-year GT graft survival was 100%, 77%, and 77%, respectively. 1-, 5-, and 10-year patient survival was 100%, 91%, and 91%, respectively. CONCLUSION: Despite the technical complexity, KAGT and SKAGT for pediatric GT recipients that develop KF can be performed with favorable outcomes.

Living donor liver transplantation for colorectal cancer liver metastases: Midterm outcomes at a single center in North America.

In recent years, liver transplantation has emerged as a treatment for patients with stage IV colorectal liver metastases (CRLM). Given the limited number of available deceased donor grafts, the use of living donor liver transplantation (LDLT) can be an important option. We performed a retrospective analysis of 10 patients that underwent LDLT for CRLM at our institution. A total of 90% of patients were male, with median age of 58 years and median model for end-stage liver disease score of 11 (range: 6-32). The rectum was the most common primary location (40%). Synchronous liver tumors were found in 50%. Pretransplant patients underwent resection (60%), hepatic-artery infusion pumping (50%), and/or radiofrequency ablation (50%). Everybody underwent adjuvant chemotherapy. Median cold ischemia time was 103 minutes (range: 93-207 minutes), and median total OR time was 11.5 hours (range: 8.5-13.9 hours). In total, 30% of patients had postoperative complications requiring reoperation. Mean recurrence-free survival was 2.2 years (95% confidence interval, 1.2-3.2 years), and mean overall survival was 3.0 years (95% confidence interval, 2.5-3.6 years). In total, 30% of patients suffered a recurrence, and 90% of patients are currently alive. This study represents the largest single-center analysis in North America of patients undergoing LDLT for CRLM. LDLT is a safe and effective alternative for patients with CRLM who do not have progressive disease or extrahepatic metastasis.

Safety of Patients with Renal Artery Aneurysm to Proceed with Living Donation.

BACKGROUND: Renal artery aneurysm (RAA) is a rare condition that involves dilation of all layers of the arterial wall of the renal artery. The risk of rupture is rare, but intervention is recommended for larger aneurysms. Surgical decision-making regarding live donor renal transplantation (LDRT) centers around safety for the living donor, and laterality of the donated kidney is based on providing the donor with the best longevity pertaining to the remaining kidney. We looked to review our long-term outcomes surrounding live donor transplants from donors with RAA with ex vivo resection and reconstruction prior to implantation. METHODS: A retrospective review was done of all laparoscopic live donor transplant nephrectomies with ex vivo aneurysm resection, reconstruction, and implantation at a single center. RESULTS: Three pairs of patients underwent successful laparoscopic donor nephrectomy, RAA resection, reconstruction, and transplantation of kidney. 2 males and 1 female ages 47 to 58 years of age underwent transplantation. The donors at 5 years of follow-up were noted to be functioning appropriately with no long-term sequelae of their donation and a mean remanent kidney function of 63 mL/min. DISCUSSION: For potential live donors with asymptomatic, unilateral renal artery aneurysm and no systemic disease, live donation with ex vivo resection and reconstruction can be performed with excellent long-term donor and recipient outcomes.

Association of body mass index with post-liver transplant outcomes.

BACKGROUND: Patients with obesity have inferior outcomes after general surgery procedures, but studies evaluating post-liver transplant (LT) outcomes have been limited by small sample sizes or lack of granularity of outcomes. We evaluated the relationship between obesity and post-LT outcomes, including those observed in other populations to be obesity-related. METHODS: Included were 1357 LT recipients prospectively enrolled in the ambulatory pre-LT setting at 8 U.S. CENTERS: Recipient were categorized by body mass index (BMI, kg/m2 ): non-obese (BMI < 30), class 1 obesity (BMI 30-<35), and classes 2-3 obesity (BMI ≥ 35). Post-transplant complications were compared by BMI using Chi-square and rank-sum testing, logistic regression, Kaplan-Meier curves, and Cox regression. RESULTS: Classes 2-3 obesity was associated with higher adjusted odds than non-obesity of venous thrombosis [adjusted odds ratio (aOR) 2.06, 95% CI 1.01-4.23, p = .047] and wound dehiscence (aOR 2.45, 95% CI 1.19-5.06, p = .02). Compared with non-obese recipients, post-LT hospital stay was significantly longer for recipients with classes 2-3 obesity [p = .01; median (Q1-Q3) 9 (6-14) vs. 8 (6-12) days) or class 1 obesity [p = .002; 9 (6-14) vs. 8 (6-11) days].  Likelihood of ICU readmission, infection, discharge to a non-home facility, rejection, 30-day readmission, and 1-year readmission were similar across BMI categories (all p > .05). CONCLUSION: Compared to non-obese recipients, obese recipients had similar post-LT survival but longer hospital stay and higher likelihood of wound dehiscence and venous thrombosis. These findings underscore that obesity alone should not preclude LT, but recipients with obesity should be monitored for obesity-related complications such as wound dehiscence and venous thrombosis.

Development and validation of a REcurrent Liver cAncer Prediction ScorE (RELAPSE) following liver transplantation in patients with hepatocellular carcinoma: Analysis of the US Multicenter HCC Transplant Consortium.

HCC recurrence following liver transplantation (LT) is highly morbid and occurs despite strict patient selection criteria. Individualized prediction of post-LT HCC recurrence risk remains an important need. Clinico-radiologic and pathologic data of 4981 patients with HCC undergoing LT from the US Multicenter HCC Transplant Consortium (UMHTC) were analyzed to develop a REcurrent Liver cAncer Prediction ScorE (RELAPSE). Multivariable Fine and Gray competing risk analysis and machine learning algorithms (Random Survival Forest and Classification and Regression Tree models) identified variables to model HCC recurrence. RELAPSE was externally validated in 1160 HCC LT recipients from the European Hepatocellular Cancer Liver Transplant study group. Of 4981 UMHTC patients with HCC undergoing LT, 71.9% were within Milan criteria, 16.1% were initially beyond Milan criteria with 9.4% downstaged before LT, and 12.0% had incidental HCC on explant pathology. Overall and recurrence-free survival at 1, 3, and 5 years was 89.7%, 78.6%, and 69.8% and 86.8%, 74.9%, and 66.7%, respectively, with a 5-year incidence of HCC recurrence of 12.5% (median 16 months) and non-HCC mortality of 20.8%. A multivariable model identified maximum alpha-fetoprotein (HR = 1.35 per-log SD, 95% CI,1.22-1.50, p < 0.001), neutrophil-lymphocyte ratio (HR = 1.16 per-log SD, 95% CI,1.04-1.28, p < 0.006), pathologic maximum tumor diameter (HR = 1.53 per-log SD, 95% CI, 1.35-1.73, p < 0.001), microvascular (HR = 2.37, 95%-CI, 1.87-2.99, p < 0.001) and macrovascular (HR = 3.38, 95% CI, 2.41-4.75, p < 0.001) invasion, and tumor differentiation (moderate HR = 1.75, 95% CI, 1.29-2.37, p < 0.001; poor HR = 2.62, 95% CI, 1.54-3.32, p < 0.001) as independent variables predicting post-LT HCC recurrence (C-statistic = 0.78). Machine learning algorithms incorporating additional covariates improved prediction of recurrence (Random Survival Forest C-statistic = 0.81). Despite significant differences in European Hepatocellular Cancer Liver Transplant recipient radiologic, treatment, and pathologic characteristics, external validation of RELAPSE demonstrated consistent 2- and 5-year recurrence risk discrimination (AUCs 0.77 and 0.75, respectively). We developed and externally validated a RELAPSE score that accurately discriminates post-LT HCC recurrence risk and may allow for individualized post-LT surveillance, immunosuppression modification, and selection of high-risk patients for adjuvant therapies.

Outcomes in liver transplant recipients with nonalcoholic fatty liver disease-related HCC: results from the US multicenter HCC transplant consortium.

NAFLD will soon be the most common indication for liver transplantation (LT). In NAFLD, HCC may occur at earlier stages of fibrosis and present with more advanced tumor stage, raising concern for aggressive disease. Thus, adult LT recipients with HCC from 20 US centers transplanted between 2002 and 2013 were analyzed to determine whether NAFLD impacts recurrence-free post-LT survival. Five hundred and thirty-eight (10.8%) of 4981 total patients had NAFLD. Patients with NAFLD were significantly older (63 vs. 58, p<0.001), had higher body mass index (30.5 vs. 27.4, p<0.001), and were more likely to have diabetes (57.3% vs. 28.8%, p<0.001). Patients with NAFLD were less likely to receive pre-LT locoregional therapy (63.6% vs. 72.9%, p<0.001), had higher median lab MELD (15 vs. 13, p<0.001) and neutrophil-lymphocyte ratio (3.8 vs. 2.9, p<0.001), and were more likely to have their maximum pre-LT alpha fetoprotein at time of LT (44.1% vs. 36.1%, p<0.001). NAFLD patients were more likely to have an incidental HCC on explant (19.4% vs. 10.4%, p<0.001); however, explant characteristics including tumor differentiation and vascular invasion were not different between groups. Comparing NAFLD and non-NAFLD patients, the 1, 3, and 5-year cumulative incidence of recurrence (3.1%, 9.1%, 11.5% vs. 4.9%, 10.1%, 12.6%, p=0.36) and recurrence-free survival rates (87%, 76%, and 67% vs. 87%, 75%, and 67%, p=0.97) were not different. In competing risks analysis, NAFLD did not significantly impact recurrence in univariable (HR: 0.88, p=0.36) nor in adjusted analysis (HR: 0.91, p=0.49). With NAFLD among the most common causes of HCC and poised to become the leading indication for LT, a better understanding of disease-specific models to predict recurrence is needed. In this NAFLD cohort, incidental HCCs were common, raising concerns about early detection. However, despite less locoregional therapy and high neutrophil-lymphocyte ratio, explant tumor characteristics and post-transplant recurrence-free survival were not different compared to non-NAFLD patients.

Virtual crossmatch for deceased donor kidney transplantation in the United States: A survey of histocompatibility lab directors and transplant surgeons.

Virtual crossmatch (VXM) is used as an alternative to or in conjunction with a cell-based physical crossmatch (PXM) for assessing HLA (human leukocyte antigen) compatibility prior to deceased donor kidney transplantation (DDKT). Data on practice patterns and perceptions regarding VXM use in the US are limited. We performed a survey of US HLA directors and transplant surgeons regarding HLA testing and crossmatch strategies. 53 (56 %) HLA directors and 68 surgeons (representing âˆ¼ 23 % of US transplant centers) completed the survey. Both groups agreed that VXM could reduce cold ischemia time (CIT), costs and improve allocation efficiency. VXM use increased following the 2021 kidney allocation change. Reducing CIT was the primary reason for favoring VXM over PXM. Preference for VXM reduced as candidates' panel reactive antibodies increased. Regulations, program policies and limitations of HLA technology were cited as important reasons for preferring PXM over VXM. Surgeons reported similar perceptions, but findings are limited by the low response rate. Finally, half the labs reported lacking specific protocols for VXM use. In conclusion, improved HLA technology and protocols along with changes to institutional procedures and policy regulations are needed for safer expansion of VXM in DDKT.

Early Effect of the Circular Model of Kidney Allocation in the United States.

BACKGROUND: In March 2021, the United States implemented a new kidney allocation system (KAS250) for deceased donor kidney transplantation (DDKT), which eliminated the donation service area-based allocation and replaced it with a system on the basis of distance from donor hospital to transplant center within/outside a radius of 250 nautical miles. The effect of this policy on kidney discards and logistics is unknown. METHODS: We examined discards, donor-recipient characteristics, cold ischemia time (CIT), and delayed graft function (DGF) during the first 9 months of KAS250 compared with a pre-KAS250 cohort from the preceding 2 years. Changes in discards and CIT after the onset of COVID-19 and the implementation of KAS250 were evaluated using an interrupted time-series model. Changes in allocation practices (biopsy, machine perfusion, and virtual cross-match) were also evaluated. RESULTS: Post-KAS250 saw a two-fold increase in kidneys imported from nonlocal organ procurement organizations (OPO) and a higher proportion of recipients with calculated panel reactive antibody (cPRA) 81%-98% (12% versus 8%; P <0.001) and those with >5 years of pretransplant dialysis (35% versus 33%; P <0.001). CIT increased (mean 2 hours), including among local OPO kidneys. DGF was similar on adjusted analysis. Discards after KAS250 did not immediately change, but we observed a statistically significant increase over time that was independent of donor quality. Machine perfusion use decreased, whereas reliance on virtual cross-match increased, which was associated with shorter CIT. CONCLUSIONS: Early trends after KAS250 show an increase in transplant access to patients with cPRA>80% and those with longer dialysis duration, but this was accompanied by an increase in CIT and a suggestion of worsening kidney discards.

Textbook Outcomes After Open Live Donor Right Hepatectomy and Open Right Hepatic Lobectomy for Cancer in 686 patients: Redefining the Benchmark.

OBJECTIVE: To compare textbook outcomes (TO) of open live donor right hepatectomy (RH) versus open right hepatic lobectomy for cancer in a single Western center and to identify clinical factors associated with failure to achieve a TO. BACKGROUND: TO, a composite quality measure that captures multiple aspects of perioperative care, has not been thoroughly studied in open RH. We hypothesized that TO rates after RH for live donor transplant could represent the "best-achievable" results of this operation and could serve as the benchmark for RH performed for an oncologic indication. METHODS: A prospective database was reviewed to compare TO rates after RH for live donor purposes versus RH for cancer at a single center from 2010 to 2020. A TO was defined as achieving 7 metrics: no perioperative transfusion, no major postoperative complications, no significant bile leak, no unplanned transfer to the ICU, no 30-day mortality, no 30-day readmission, and no R1 margins for cancer cases. RESULTS: Among 686 RH patients (371 live donor and 315 cancer cases), a TO was achieved in 92.2% of RH donors and 53.7% of RH cancer cases. Live donor patients tended to be younger, healthier, and thinner. Among donors, increased intraoperative blood loss, and in cancer cases, male sex, tumor size, and increased intraoperative blood loss were associated with TO failure. CONCLUSIONS: A TO can be achieved in over 90% of patients undergoing living donor RH and in approximately half of RH cancer cases. These metrics represent a new benchmark for "real-world" TO after open RH.

Reversal of Roux-en-Y Gastric Bypass for Successful Salvage of Renal Allograft.

Enteric hyperoxaluria (EH) is a known complication of Roux-en-Y gastric bypass (RYGB) and can lead to nephrolithiasis, oxalate-induced nephropathy, and end-stage renal disease. Recurrent EH-induced renal impairment has been reported after kidney transplantation and may lead to allograft loss. EH occurs in up to one quarter of patients following malabsorption-based bariatric operations. We present a report of medically refractory EH in a renal transplant recipient with allograft dysfunction that was successfully managed with reversal of RYGB. The patient developed renal failure 7 years following gastric bypass requiring renal transplant. Following an uneventful living donor kidney transplant, the patient developed recurrent subacute allograft dysfunction. A diagnosis of oxalate nephropathy was made based on biopsy findings of renal tubular calcium oxalate deposition in conjunction with elevated serum oxalate levels and elevated 24-hr urinary oxalate excretion. Progressive renal failure ensued despite medical management. The patient underwent reversal of her RYGB, which resulted in recovery of allograft function. This report highlights an under-recognized, potentially treatable cause of renal allograft failure in patients with underlying gastrointestinal pathology or history of bariatric surgery and proposes a strategy for management of patients with persistent hyperoxaluria based on a review of the literature.

Poor Outcomes of Patients With NAFLD and Moderate Renal Dysfunction or Short-Term Dialysis Receiving a Liver Transplant Alone.

The outcomes of patients with moderate renal impairment and the impact of liver disease etiology on renal function recovery after liver transplant alone (LTA) are largely unknown. We explored whether NAFLD patients with pre-LTA moderate renal dysfunction (GFR 25-45 ml/min/1.73 m2) may be more susceptible to develop post-LTA severe renal dysfunction (GFR<15 ml/min/1.73 m2) than ALD patients, as well as other overall outcomes. Using the UNOS/OPTN database, we selected patients undergoing liver transplant for NAFLD or ALD (2006-2016), 15,103 of whom received LTA. NAFLD patients with moderate renal dysfunction were more likely to develop subsequent GFR<15 ml/min/1.73 m2 than ALD patients (11.1% vs. 7.38%, p < 0.001). Patients on short-term dialysis pre-LTA (≤12 weeks) were more likely to develop severe renal dysfunction (31.7% vs. 18.1%), especially in NAFLD patients, and were more likely to receive a further kidney transplant (15.3% vs. 3.7%) and had lower survival (48.6% vs. 50.4%) after LTA (p < 0.001 for all). NAFLD was an independent risk factor for post-LTA severe renal dysfunction (HR = 1.2, p = 0.02). NAFLD patients with moderate renal dysfunction and those receiving short-term dialysis prior to LTA are at a higher risk of developing subsequent severe renal dysfunction. Underlying etiology of liver disease may play a role in predicting development and progression of renal failure in patients receiving LTA.

Back Table Preparation of the Right Lobe Live Donor Liver Allograft: A Crucial Part of the Adult Live Donor Liver Transplant Procedure.

INTRODUCTION: We aimed to describe our procedure for vascular reconstruction and back table bench preparation for the right lobe live donor allograft. Live donor liver transplantation (LDLT) remains an important option for the expansion of the donor pool. The procedure has been widely used, and its success is dependent on a technically perfect operation with appropriate inflow and outflow of the allograft. Adequate preparation of the right lobe (RL) allograft prior to implantation remains a vital part of the procedure. METHODS: Our technique of back table vascular reconstruction of the RL allograft has been performed using a hepatic vein patch venoplasty, inferior hepatic vein inclusion, portal vein reconstruction, and segment V and VIII reconstruction for all of our LDLTs. RESULTS: Between March 2009 and January 2020, 321 consecutive adult LDLTs were performed and underwent back table reconstruction with the techniques described. During that time period, no patients had hepatic insufficiency. There was a single thrombosis of a superior mesenteric vein (SMV) to PV jump conduit. CONCLUSIONS: Our technique of back table reconstruction of the LDLT right lobe graft remains a crucial part of the operative procedure. Our experience with RL grafts without middle hepatic vein (MHV) and our systematic approach for inflow and outflow reconstruction has yielded excellent results with no technical outflow issues and minimal inflow complications.

Sequential liver and kidney living donors: Making the ultimate gift twice.

There are nearly 150 living donors in the United States who donated more than one solid organ. Using our divisional database, we found 20 individuals who donated a liver and a kidney at different times. We performed a retrospective chart review of these donors, studying their motivating factors, complications and outcomes. The donors included 11 (55%) males and nine females. Thirteen (65%) donated the kidney before the liver. Fourteen (70%) were nondirected donors at the first donation, and four of the six directed donors in the first donation became nondirected in the second donation. Seventeen (85%) were nondirected at the second donation. Common reasons for donating the second time were a good experience with the first donation and knowing that one can donate again. Outcomes and the incidence of early complications were not significantly different after the 2nd versus the 1st donation. All donors recovered and currently are doing well. Our results show a significant number of dual organ donors are nondirected and motivated by their strong desire to help. A positive experience with the 1st donation often was the driving factor for the 2nd. A history of previous organ donation did not negatively impact the 2nd donation.

The Clinical Impact of Anti-HLA Donor Specific Antibody Detection Through First Year Screening on Stable Kidney Transplant Recipients.

Anti-HLA Donor Specific Antibody (DSA) detection post kidney transplant has been associated with adverse outcomes, though the impact of early DSA screening on stable patients remain unclear. We analyzed impact of DSA detection through screening in 1st year stable patients (n = 736) on subsequent estimated glomerular filtration rate (eGFR), death censored graft survival (DCGS), and graft failure (graft loss including return to dialysis or re-transplant, patient death, or eGFR < 20 ml/min at last follow up). Patients were grouped using 1st year screening into DSA+ (Class I, II; n = 131) or DSA- (n = 605). DSA+ group were more DR mismatched (p = 0.02), more sensitized (cPRA ≥90%, p = 0.002), less Caucasian (p = 0.04), and had less pre-emptive (p = 0.04) and more deceased donor transplants (p = 0.03). DSA+ patients had similar eGFR (54.8 vs. 53.8 ml/min/1.73 m2, p = 0.56), DCGS (91% vs. 94%, p = 0.30), and graft failure free survival (76% vs. 82%, p = 0.11). DSA timing and type did not impact survival. Among those with a protocol biopsy (n = 515), DSA detected on 1st year screening was a predictor for graft failure on multivariate analysis (1.91, 95% CI 1.03-3.55, p = 0.04). Overall, early DSA detection in stable patients was an independent risk factor for graft failure, though only among those who underwent a protocol biopsy.

Low Daily Step Count Is Associated With a High Risk of Hospital Admission and Death in Community-Dwelling Patients With Cirrhosis.

BACKGROUND & AIMS: Daily step count measures cardiorespiratory fitness and has been associated with clinical outcomes. However, its utility in patients with cirrhosis remains largely unexplored. We aimed to investigate the association between step count, frailty metrics, and clinical outcomes in cirrhosis. METHODS: All participants underwent frailty evaluation with the liver frailty index, 6-minute walk test, and gait speed test. To monitor step count, participants were given a personal activity tracker (PAT). A subset also was invited to use Exercise and Liver FITness (EL-FIT). Daily step counts from the first week of PAT use and frailty metrics were investigated as predictors of hospital admission and mortality. RESULTS: There were 116 patients included (age, 56 ± 11 y; male, 55%; body mass index, 31 ± 7; model for end-stage liver disease-sodium, 15 ± 7). The main etiologies of cirrhosis were alcohol-related (33%) and nonalcoholic steatohepatitis (30%). Monitoring for the week was accomplished in 80% of participants given both PAT+EL-FIT vs 62% in those with PAT only (P = .04). During follow-up evaluation, hospital admission was observed in 55% and death in 15%. Kaplan-Meir curves showed increased readmission and deaths among patients performing in the lowest quartile (ie, <1200 steps/d). When adjusted by model for end-stage liver disease-sodium and EL-FIT use, the lowest quartile was associated with hospital admission and death (hazard ratio, HR [95% confidence interval], 1.90 [1.09-3.30] and 3.46 [1.23-9.68], respectively), along with the 6-minute walk test (HR, 0.63 [0.47-0.83] and 0.66 [0.44-0.99] per 100 m, respectively) and gait speed test (HR, 0.29 [0.11-0.72] and 0.21 [0.05-0.84], respectively). CONCLUSIONS: Daily step count predicted hospital admission and mortality rates in patients with cirrhosis, similar to the current standard frailty metrics. Incorporation of a physical training-dedicated smartphone application was associated with increased PAT use and step reporting.

Increasing Living Donor Liver Transplantation Using Liver Paired Exchange.

BACKGROUND: Living donor liver transplantation (LDLT) continues to be the primary modality of liver transplantation in Asia, but it accounts for about 5% of all liver transplantations in the US. ABO incompatibility is the primary reason motivated donors are declined. Although kidney paired exchanges are common, liver paired exchange (LPE) is still evolving in the US. STUDY DESIGN: This is a retrospective review (between January 1, 2019, and July 31, 2021) of our initial experience with LPE. RESULTS: A total of 10 LPEs (20 LDLTs) were performed during the study period. Seven LPEs were initiated by a nondirected O donor. The other 3 pair sets involved 1 ABO compatible and 1 ABO incompatible pair. Transplantations in a pair set were completed within a mean of 4.8 (range 1-14) days of each other. All 20 donors are doing well with no major complications at 12.7 (range 1-20) months. Seventeen of 20 recipients are alive and have good allograft function. One recipient died in the early postoperative period. Two late deaths of patients with functioning allografts were due to COVID-19 (at 8 months) and peritoneal carcinomatosis and gram-negative sepsis (at 9 months). CONCLUSIONS: LPE is feasible in a high-volume LDLT center and is a useful option to increase LDLT by overcoming ABO incompatibility. Nondirected donors can be utilized to initiate an LPE.

The Combined Roles of Race/Ethnicity and Substance Use in Predicting Likelihood of Kidney Transplantation.

BACKGROUND: Racial/ethnic minorities face known disparities in likelihood of kidney transplantation. These disparities may be exacerbated when coupled with ongoing substance use, a factor also reducing likelihood of transplantation. We examined whether race/ethnicity in combination with ongoing substance use predicted incidence of transplantation. METHODS: Patients were enrolled between March 2010 and October 2012 at the time of transplant evaluation. Substance use data were retrieved from transplant evaluations. Following descriptive analyses, the primary multivariable analyses evaluated whether, relative to the referent group (White patients with no substance use), racial/ethnic minority patients using any substances at the time of evaluation were less likely to receive transplants by the end of study follow-up (August 2020). RESULTS: Among 1152 patients, 69% were non-Hispanic White, 23% non-Hispanic Black, and 8% Other racial/ethnic minorities. White, Black, and Other patients differed in percentages of current tobacco smoking (15%, 26%, and 18%, respectively; P = 0.002) and illicit substance use (3%, 8%, and 9%; P < 0.001) but not heavy alcohol consumption (2%, 4%, and 1%; P = 0.346). Black and Other minority patients using substances were each less likely to receive transplants than the referent group (hazard ratios ≤0.45, P ≤ 0.021). Neither White patients using substances nor racial/ethnic minority nonusers differed from the referent group in transplant rates. Additional analyses indicated that these effects reflected differences in waitlisting rates; once waitlisted, study groups did not differ in transplant rates. CONCLUSIONS: The combination of minority race/ethnicity and substance use may lead to unique disparities in likelihood of transplantation. To facilitate equity, strategies should be considered to remove any barriers to referral for and receipt of substance use care in racial/ethnic minorities.

Rabbit antithymocyte globulin dose and early subclinical and clinical rejections in kidney transplantation.

Antithymocyte globulin (ATG) is a commonly used induction agent in kidney transplant recipients. However, the optimal dosing has not been well defined. Our protocol aims for a 5-6 mg/kg cumulative dose. It is unclear if a dose lower than 5 mg/kg is associated with more rejection. We performed a retrospective cohort study of patients who received a kidney transplant at our center between January 1, 2013 and December 31, 2016. Primary outcome was biopsy proven acute rejection (clinical and subclinical) in the first 6 months after kidney transplant. CMV viremia in high risk (D+/R-) recipients and BK viremia was compared as a secondary endpoint. Of the 543 patients, the Low Dose (LD) group (n = 56) received <5 mg/kg ATG and Regular Dose (RD) group (n = 487) received ≧5 mg/kg. Patients in RD were more sensitized (higher PRA and CPRA). LD received a dose of 4 ± 1.1 mg/kg ATG whereas RD received 5.6 ± .3 mg/kg ATG (P < .001). TCMR (Banff 1A or greater) was present in 34% of patients in LD versus 22% in RD (P = .04) (OR 2.1; 95%CI 1.12-3.81; P = .019). There was no difference in the incidence of CMV or BK viremia. ATG doses lower than 5 mg/kg may be associated with a heightened risk of rejection despite a low degree of sensitization.

A retrievable, dual-chamber stent protects against warm ischemia of donor organs in a model of donation after circulatory death.

BACKGROUND: Ischemic injury during the agonal period of donation after circulatory death donors remains a significant barrier to increasing abdominal transplants. A major obstacle has been the inability to improve visceral perfusion, while at the same time respecting the ethics of the organ donor. A retrievable dual-chamber stentgraft could potentially isolate the organ perfusion from systemic hypotension and hypoxia, without increasing cardiac work or committing the donor. METHODS: Retrievable dumbbell-shaped stents were laser welded from nitinol wire and covered with polytetrafluoroethylene. Yorkshire pigs were assigned to either agonal control or dumbbell-shaped dual-chamber stentgraft. A central lumen maintained aortic flow, while an outer visceral chamber was perfused with oxygenated blood. A 1-hour agonal phase of hypoxia and hypotension was simulated. Stents were removed by simple sheath advancement. Cardiac monitoring, labs, and visceral flow were recorded followed by recovery of the animal to a goal of 48 hours. RESULTS: Cardiac stress did not increase during stent deployment. Visceral pO2 and flow were dramatically improved in stented animal relative to control animals. Five of 7 control animals were killed after renal failure complications, whereas all stent animals survived. Histology confirmed increased ischemic changes among control kidneys compared to stented animals. CONCLUSION: A dual-chamber stent improved outcomes after a simulated agonal phase. The stent did not increase cardiac work, thus respecting a key ethical consideration. The ability of a dual-chamber stent to prevent ischemia during organ recovery may become a powerful tool to address the critical donor organ shortage.