Transplant center variability in utilizing nonstandard donors and its impact on the transplantation of patients with lower MELD scores.

There is a subset of patients with lower MELD scores who are at substantial risk of waitlist mortality. In order to transplant such patients, transplant centers must utilize "nonstandard" donors (eg, living donors, donation after circulatory death), which are traditionally offered to those patients who are not at the top of the waitlist. We used Organ Procurement and Transplantation data to evaluate center-level and region-level variability in the utilization of nonstandard donors and its impact on MELD at transplant among adult liver-alone non-status 1 patients transplanted from April 1, 2020, to September 30, 2022. The center-level variability in the utilization of nonstandard donors was 4-fold greater than the center-level variability in waitlisting practices (waitlistings with a MELD score of <20). While there was a moderate correlation between center-level waitlisting and transplantation of patients with a MELD score of <20 ( p = 0.58), there was a strong correlation between center-level utilization of nonstandard donors and center-level transplantation of patients with a MELD score of <20 ( p = 0.75). This strong correlation between center-level utilization of "nonstandard" donors and center-level transplantation of patients with a MELD score of <20 was limited to regions 2, 4, 5, 9, and 11. Transplant centers that utilize more nonstandard donors are more likely to successfully transplant patients at lower MELD scores. Public reporting of these data could benefit patients, caregivers, and referring providers, and be used to help maximize organ utilization.

Stepwise development and expansion of an abdominal normothermic regional perfusion program for donation after circulatory determination of death organ procurement.

INTRODUCTION: Normothermic regional perfusion (NRP) represents an innovative technology that improves the outcomes for liver and kidney recipients of donation after circulatory determination of death (DCD) organs but protocols for abdominal-only NRP (A-NRP) DCD are lacking in the US. METHODS: We describe the implementation and expansion strategies of a transplant-center-based A-NRP DCD program that has grown in volume, geographical reach, and donor acceptance parameters, presented as four eras. RESULTS: In the implementation era, two donors were attempted, and one liver graft was transplanted. In the local expansion era, 33% of attempted donors resulted in transplantation and 42% of liver grafts from donors who died within the functional warm ischemic time (fWIT) limit were transplanted. In the Regional Expansion era, 25% of attempted donors resulted in transplantation and 50% of liver grafts from donors who died within the fWIT limit were transplanted. In the Donor Acceptance Expansion era, 46% of attempted donors resulted in transplantation and 72% of liver grafts from donors who died within the fWIT limit were transplanted. Eight discarded grafts demonstrated a potential opportunity for utilization. CONCLUSION: The stepwise approach to building an A-NRP program described here can serve as a model for other transplant centers.

Six-month abdominal transplant recipient outcomes from donation after circulatory death heart donors: A retrospective analysis by procurement technique.

Standard US practice for donation after circulatory death (DCD) abdominal organ procurement is superrapid recovery (SRR). A newer approach using thoracoabdominal normothermic regional perfusion (TA-NRP) shows promise for better recipient outcomes for all organs, but there are few reports of abdominal recipient outcomes from TA-NRP donors. We used the United Network for Organ Sharing data to identify all cardiac DCD donors from October 1, 2020, to May 20, 2022, and categorized them by recovery procedure (SRR vs TA-NRP). We then identified all liver, kidney, and pancreas recipients of these donors for whom 6-month outcome data were available and compared patient and graft survival, kidney delayed graft function (DGF), and biliary complications between TA-NRP DCD and SRR DCD organ recipients. Patient and graft survival did not differ significantly between groups for either kidney or liver recipients. Significantly fewer TA-NRP kidney recipients developed DGF (12.7% [15/118] vs 42.0% [84/200], P <.001), and TA-NRP and pumped kidneys had lower odds for DGF on multivariate analysis. No liver recipients in either group had biliary complications or were relisted for transplantation for ischemic cholangiopathy. Although long-term outcomes need to be investigated, our early results show similar outcomes for recipients of TA-NRP DCD abdominal organs versus recipients of SRR DCD abdominal organs. We believe that TA-NRP is an effective approach to expand the use of DCD organs.

Neonatal Outcomes after Uterus Transplantation: Dallas Uterus Transplant Study.

OBJECTIVE: Limited data are available on the outcome of infants born after uterus transplantation. Our aim was to describe the hospital course and laboratory findings in the first 2 months of life of the 12 infants born in the Dallas UtErus Transplant Study (DUETS). STUDY DESIGN: Based on the trial protocol, information about infants was collected in a prospective fashion, including infant demographics, hospital course, and laboratory values. RESULTS: Twelve infants were delivered, all by cesarean section, from 11 mothers who had undergone uterus transplantation (one mother had two pregnancies and delivered two babies). All pregnancies were singleton. The mothers received immunosuppressive therapy, and one had a rejection episode that was detected during pregnancy. The rejection episode resolved after steroid treatment. The infants had a median gestational age of 366/7 weeks (range: 306/7-380/7 weeks) and median birth weight of 2,920 g (range: 1,770-3,470 g). The lowest Apgar's score at 5 minutes was 8. All infants were appropriate size for gestational age. Two infants presented with bandemia but negative blood cultures. At 2 months of age, all infants achieved the developmental and behavioral milestones outlined by the American Academy of Pediatrics. CONCLUSION: The 12 infants born from mothers with uterus transplants had a neonatal course that reflected the gestational age at delivery. No baby was born with an identified malformation or organ dysfunction. Longer follow-up and a larger number of infants are needed to confirm these observations. KEY POINTS: · Normal fetal development after uterus transplantation.. · No baby was born with malformations or showed any organ dysfunction.. · At 2 months, all infants achieved appropriate developmental and behavioral milestones..

Ratio of hepatic arterial flow to recipient body weight predicts biliary complications after deceased donor liver transplantation.

OBJECTIVES: Adequate hepatic arterial (HA) flow to the bile duct is essential in liver transplantation. This study was conducted to determine if the ratio of directly measured HA flow to weight is related to the occurrence of biliary complications after deceased donor liver transplantation. METHODS: A retrospective review of 2684 liver transplants carried out over a 25-year period was performed using data sourced from a prospectively maintained database. Rates of biliary complications (biliary leaks, anastomotic and non-anastomotic strictures) were compared between two groups of patients with HA flow by body weight of, respectively, <5 ml/min/kg (n = 884) and ≥5 ml/min/kg (n = 1800). RESULTS: Patients with a lower ratio of HA flow to weight had higher body weight (92 kg versus 76 kg; P < 0.001) and lower HA flow (350 ml/min versus 550 ml/min; P < 0.001). A lower ratio of HA flow to weight was associated with higher rates of biliary complications at 2 months, 6 months and 12 months (19.8%, 28.2% and 31.9% versus 14.8%, 22.4% and 25.8%, respectively; P < 0.001). CONCLUSIONS: A ratio of HA flow to weight of < 5 ml/min/kg is associated with higher rates of biliary complications. This ratio may be a useful parameter for application in the prevention and early detection of biliary complications.

Utilization of a SARS-CoV-2-positive donor for liver transplantation.

Liver transplantation rates have been negatively affected by the pandemic caused by coronavirus disease 2019 (COVID-19), the disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Current practice in the liver transplant community is to avoid utilizing SARS-CoV-2-positive donors for liver transplantation unless there is a compelling reason such as recipient illness severity. In this case, we report the use of a donor who had a positive exposure to and symptom history for COVID-19 and tested positive for SARS-CoV-2 on admission for a liver transplant recipient with primary sclerosing cholangitis and a Model of End-Stage Liver Disease score of 23 with no known COVID-19 exposures. We focus on the decision to accept this particular organ, as well as the discussion with the recipient about the unknowns of disease transmission and risk associated with this donor. The current case argues that transplant programs should begin to consider low-risk donors with positive SARS-CoV-2 testing for recipients who have the potential to benefit from liver transplantation, which may not only be those with the most severe illness.

Twelve Live Births After Uterus Transplantation in the Dallas UtErus Transplant Study.

OBJECTIVE: To describe aggregated pregnancy outcomes after uterus transplantation from a single, experienced center. METHODS: This prospective study reports on live births among 20 women who received a uterus transplant from 2016 to 2019 at Baylor University Medical Center at Dallas. These live births occurred between November 2017 and September 2020. The main measures were live birth, maternal complications, and fetal and newborn outcomes. RESULTS: There were six graft failures (four surgical complications and two with poor perfusion postoperatively). Of the 14 technically successful transplants, at least one live birth occurred in 11 patients. Thus far, the live birth rate per attempted transplant is 55%, and the live-birth rate per technically successful transplant is 79%. Ten uteri were from nondirected living donors and one uterus was from a deceased donor. In vitro fertilization was performed to achieve pregnancy. Ten recipients delivered one neonate, and one recipient delivered two neonates. One organ rejection episode was detected during pregnancy and was resolved with steroids. The median birth weight was 2,890 g (range 1,770-3,140 g [median 68th percentile]). Maternal weight gain was higher than Institute of Medicine recommendations. Maternal medical complications were observed in five recipients (elevated creatinine level, gestational diabetes, gestational hypertension [n=2], and preeclampsia). In five recipients, maternal medical or obstetric complications led to an unplanned preterm delivery (elevated creatinine level, preeclampsia; preterm labor [n=3]). The median gestational age at delivery was 36 6/7 weeks (range 30 6/7-38 weeks). All neonates were liveborn, with Apgar scores of 8 or higher at 5 minutes. CONCLUSION: Over the first 3 years, our program experienced a live-birth rate per attempted transplant of 55% and a live-birth rate per technically successful transplant of 79%. In our experience, uterus transplantation resulted in a third-trimester live birth in all cases in which pregnancies reached 20 weeks of gestation. Maternal medical and obstetric complications can occur; however, these were manageable by applying principles of generally accepted obstetric practice. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov, NCT02656550.

Dallas UtErus Transplant Study: Early Outcomes and Complications of Robot-assisted Hysterectomy for Living Uterus Donors.

BACKGROUND: Uterus transplantation is a treatment for absolute uterine infertility and can be performed with living and deceased donors. Given the safety and increased utilization of robotic assistance with other gynecologic and transplant donor operations, we adopted a robot-assisted approach to donor hysterectomy. This study compared early outcomes and morbidity of the robot-assisted approach to donor hysterectomy with the traditionally performed open approach and addressed whether the robot-assisted approach is safe and offers advantages for the donor. METHODS: Our institution has performed 18 living donor hysterectomies for uterus transplantation. This retrospective review compared the last 5 cases utilizing a robot-assisted technique and vaginal extraction of the uterus graft with the first 13 cases performed with an open laparotomy technique. Demographic, intraoperative, and postoperative data were examined. RESULTS: There were no differences between the robot-assisted and the open living donor group with respect to age, body mass index, or gynecological history. Although the median operative time was shorter for the open approach (6.27 versus 10.46 h), the donors' median estimated blood loss, length of hospital stay, and length of sick leave were less with the robot-assisted approach. There was no conversion to open hysterectomy in the robot-assisted cases, and the incidence of complications was similar between the 2 groups. There was no difference in early graft function. CONCLUSIONS: These preliminary results show that robot-assisted living donor hysterectomy is feasible and safe for the donors; it allows a faster postoperative recovery and the same early graft function.

Cost Analysis of Liver Acquisition Fees Before and After Acuity Circle Policy Implementation.

Importance: Acuity circles (AC) liver allocation policy was implemented to eliminate donor service area geographic boundaries from liver allocation and to decrease variability in median Model of End-stage Liver Disease (MELD) score at transplant and wait list mortality. However, the broader sharing of organs was also associated with more flights for organ procurements and higher costs associated with the increase in flights. Objective: To determine whether the costs associated with liver acquisition changed after the implementation of AC allocation. Design, Setting, and Participants: This single-center cost comparison study analyzed fees associated with organ acquisition before and after AC allocation implementation. The cost data were collected from a single transplant institute with 2 liver transplant centers, located 30 miles apart, in different donation service areas. Cost, recipient, and transportation data for all cases that included fees associated with liver acquisition from July 1, 2019, to October 31, 2020, were collected. Exposures: Primary liver offer acceptance with associated organ procurement organization or charter flight fees. Main Outcomes and Measures: Specific fees (organ acquisition, surgeon, import, and charter flight fees) and total fees per donor were collected for all accepted liver donors with at least 1 associated fee during the study period. Results: Of 213 included donors, 171 were used for transplant; 90 of 171 (52.6%) were male, and the median (interquartile range) age of donors was 41.0 (30.0-52.8) years in the pre-AC period and 36.9 (24.0-48.8) years in the post-AC period. There was no significant difference in the post-AC compared with pre-AC period in median (range) MELD score (24 [8-40] vs 25 [6-40]; P = .27) or median (range) match run sequence (15 [1-3951] vs 10 [1-1138]; P = .31), nor in mean (SD) distance traveled (155.83 [157.00] vs 140.54 [144.33] nautical miles; P = .32) or percentage of donors requiring flights (58.5% [69 of 118] vs 56.8% [54 of 95]; P = .82). However, costs increased significantly in the post-AC period: total cost increased 16% per accepted donor (mean [SD] of $52 966 [13 278] vs $45 725 [9300]; P < .001) and 55% per declined donor (mean [SD] of $15 865 [3942] vs $10 217 [4853]; P < .001). Contributing factors included more than 2-fold increases in the proportions of donors incurring import fees (31.4% [37 of 118] vs 12.6% [12 of 95]; P = .002) and surgeon fees (19.5% [23 of 118] vs 9.5% [9 of 95]; P = .05), increased acquisition fees (10% increase; mean [SD] of $43 860 [3266] vs $39 980 [2236]; P < .001), and increased flight expenses (43% increase; mean [SD] of $12 904 [6066] vs $9049 [5140]; P = .002). Conclusions and Relevance: The unintended consequences of implementing broader sharing without addressing organ acquisition fees to account for increased importation between organ procurement organizations must be remedied to contain costs and ensure viability of transplant programs.

Effect of subcutaneous tissue depth on outcomes of kidney transplantation.

Although post-kidney transplant (KT) wound complications are associated with elevated body mass index (BMI), BMI is not an accurate surrogate of obesity. On the other hand, subcutaneous depth (SQD) measurement is a direct marker of truncal obesity. We examined outcomes of differing intraoperative SQD measurements in 113 KT-only recipients over 20 months. Recipients' median age was 51 years; median BMI, 28 kg/m2; and mean SQD, 2.9 cm. Patients were stratified into groups of SQD ≤2.5 cm, >2.5-5 cm, and >5 cm. An SQD of >2.5 to 5 cm correlated with a BMI of 30 kg/m2 (obesity) and an SQD >5 cm correlated with a BMI >35 kg/m2 (severe obesity). Degree of SQD was not associated with more frequent technical complications such as fascial dehiscence, lymphocele formation, renal artery thrombosis/stenosis, urine leak, or ureteral stenosis. However, an SQD >2.5 cm was a risk factor for requiring a wound vacuum-assisted closure device. There was no difference in graft or patient survival among the three SQD groups. Obesity, as measured directly by SQD, was not associated with increased technical complications or poor outcomes after KT. As expected, there was a higher incidence of wound complications in the higher SQD groups requiring intervention.

The role of multiorgan procurement for abdominal transplant in general surgery resident education.

BACKGROUND: To assess the impact of participation of multiorgan procurement (MP) by general surgery (GS) residents on surgical knowledge and skills, a prospective cohort study of GS residents during transplant surgery rotation was performed. METHODS: Before and after participation in MPs, assessment of knowledge was performed by written pre and post tests and surgical skills by modified Objective Structured Assessment of Technical Skill (OSATS) score. Thirty-nine residents performed 84 MPs. RESULTS: Significant improvement was noted in the written test scores (63.3% vs 76.7%; P < 0.001). Better surgical score was associated with female gender (15.4 vs 13.3, P = <0.01), prior MP experience (16.2 vs 13.7, P = 0.03), and senior level resident (15.1 vs 13.0, P = 0.03). Supraceliac aortic dissection (P = 0.0017) and instrument handling (P = 0.041) improved with more MP operations. CONCLUSIONS: Participation in MP improves residents' knowledge of abdominal anatomy and surgical technique.

Low Measured Hepatic Artery Flow Increases Rate of Biliary Strictures in Deceased Donor Liver Transplantation: An Age-Dependent Phenomenon.

BACKGROUND: This study was conducted to determine effect of lower measured hepatic arterial (HA) flow (<400 mL/min) on biliary complications and graft survival after deceased donor liver transplantation. Hepatic artery is the main blood supply to bile duct and lack of adequate HA flow is thought to be a risk factor for biliary complications. METHODS: A retrospective review of 1300 patients who underwent deceased donor liver transplantation was performed. Patients with arterial complications were excluded to eliminate potential contribution to biliary complications from HA thrombosis. Patients were divided into low (<400 mL/min; N = 201) and high (≥400 mL/min; N = 1099) HA flow groups. Incidence of biliary complications and graft survival were analyzed. RESULTS: HA flows less than 400 mL/min were associated with increased rate of biliary strictures in younger donors (<50 years old), and in patients with duct-to-duct anastomoses (P = 0.028). Lower HA flows were associated with decreased graft survival (P = 0.013). Donor older than 50 years was associated with increased rate of biliary strictures (hazard ratio [HR], 1.67; 95% confidence interval [CI], 1.14-2.45; P = 0.0085) and graft failure (HR, 1.68; 95% CI, 1.35-2.1; P <0.0001) on multivariate analyses. HA flow less than 400 mL/min was associated with biliary strictures (HR, 1.53; 95% CI, 1.04-2.24; P = 0.0297) on univariate analysis only. CONCLUSIONS: HA flow less than 400 mL/min was associated with higher rate of biliary strictures in younger donors with duct-to-duct reconstruction and lower graft survival. A consideration should be given to increase the intraoperative HA flow to prevent biliary strictures in such patients.

Glutathione depletion of stimulator cells inhibits responder T-cell immunogenicity in vitro and prolongs allograft survival in vivo.

BACKGROUND: Pretransplant donor-organ immunomodulation may attenuate allograft rejection by changing the redox state of donor cells. This study explored impact of donor-cell redox-state alteration by glutathione (GSH) depletion on graft immunogenicity. METHODS: Splenic and heart endothelial cells from Balb/c mice were treated with diethylmaleate (a GSH-depleting agent) and/or lipopolysaccharide to assess the impact of GSH depletion on alloreactivity by mixed lymphocyte reaction, endothelial cell adhesion by T-cell adhesion assay, intracellular adhesion molecule-1 expression by reverse transcriptionase-polymerase chain reaction, and nuclear factor-kappa B upregulation by electrophoretic mobility shift assay. Heterotopic heart transplants were performed as in vivo correlate. RESULTS: GSH depletion decreased endothelial cell and splenic cell alloreactivity, decreased endothelial cell intracellular adhesion molecule-1 expression through attenuation of nuclear factor-kappa B activity, decreased endothelial cell adhesion, and prolonged heterotopic heart transplant graft survival. CONCLUSIONS: GSH depletion may represent a significant immunomodulator of donor antigenicity to prevent transplant rejection.

Liver nonparenchymal cells involved in hyporesponsiveness induced by portal vein injection of alloantigen.

INTRODUCTION: Intrahepatic injection of alloantigen prolongs allograft survival and inhibits T-lymphocyte release of both IL-2 and IFN-gamma but not IL-4. This suggests that intrahepatic processing of antigen lead to a predominance of Th2 cell population with inhibition of Th1 cell type. This study examines the effects of hepatic nonparenchymal cells (NPCs) on T cell function and cytokine mRNA expression profiles. MATERIALS AND METHODS: Following portal vein (p.v.) injection of allogeneic splenic mononuclear cells (SMNC) in mice, heterotopic cardiac allograft survival and donor-specific immune responses were assessed. The cytokine profiles were evaluated in heart grafts and spleens from transplanted mice, or in recipient lymphocytes stimulated in vitro with alloantigen. The immunoregulatory role of NPCs from p.v. injected mice was evaluated. RESULTS: Transplanted mice with prolonged graft survival demonstrated increased IL-4, TGF-beta and IL-10 and/or decreased IFN-gamma and IL-2 mRNA expression within the spleen and the transplanted graft. This correlated with increased antigen-specific IL-4, IL-10 and TGF-beta expression in lymphocytes isolated from the p.v. injected mice. In mixed lymphocyte cultures using NPC from p.v. injected mice as regulatory cells, there was decreased proliferation of lymphocytes from the p.v. injected mice in response to allogeneic stimulation, associated with increased IL-4, TGF-beta and IL-10 production and decreased IFN-gamma and IL-2 production. The regulatory effects of the NPC was reversed by prostaglandin E inhibitor. CONCLUSIONS: Interactions between allogeneic lymphocytes and NPCs results in an impaired Th1 response and preferential shift towards a Th2 cytokine response which may regulate allograft rejection.

A role for matrix metalloproteinases and tumor host interaction in hepatocellular carcinomas.

BACKGROUND: Hepatocellular carcinoma (HCC) occur in livers with injury-remodeling, accomplished by enzymes called matrix metalloproteinases (MMP). Metastasis involves basement membrane invasion also caused by MMP activity. Alterations in MMP expression and their endogenous inhibitor (TIMP) may factor in HCC metastasis. METHODS: HCC specimens and lymph nodes (n = 7), and normal lymph tissue from organ donors (n = 8), were snap-frozen in liquid nitrogen and the mRNA precipitated. A series of reverse transcription-polymerase chain reactions (RT-PCR) were performed using MMP (MMP2, MMP7, MMP9) primers and TIMP (TIMP1, TIMP2) primers. These were semiquantitatively analyzed by comparing concentration with constitutive GADPH expression. RESULTS: There is an increase in MMP2:TIMP2 mRNA expression ratio in the normal and tumor margin tissue compared to the tumor. There are increases in all MMP and TIMP mRNA expression (except TIMP1) and alterations in all of the MMP:TIMP expression ratios in the draining lymph node. CONCLUSIONS: Alterations exist in MMP2:TIMP2: expression at the margin, and all of the MMPs in the draining lymph nodes. This likely reflects a host-tumor interaction that regulates tumor metastasis.

Posttransplant lymphoproliferative disorder presenting as a small bowel obstruction in a patient with pancreas transplantation alone.

Posttransplant lymphoproliferative disorder (PTLD) is a well-known complication associated with the transplant recipient. We chronicle a case of PTLD in a failed graft presenting as a small bowel obstruction in a pancreas-only transplant patient. While typical symptoms may be elusive in the complex immunosuppressed patient, graft pain along with persistent graft pancreatitis and a positive Epstein-Barr viremia should raise suspicion for an underlying PTLD.