Faculty Bibliography

Background:The COVID-19 pandemic strained hospital resources in New York City, including those for providing dialysis. New York University Medical Center and affiliations, including New York City Health and Hospitals/Bellevue, developed a plan to offset the increased needs for KRT. We established acute peritoneal dialysis (PD) capability, as usual dialysis modalities were overwhelmed by COVID-19 AKI. Methods:Observational study of patients requiring KRT admitted to Bellevue Hospital during the COVID surge. Bellevue Hospital is one of the largest public hospitals in the United States, providing medical care to an underserved population. There were substantial staff, supplies, and equipment shortages. Adult patients admitted with AKI who required KRT were considered for PD. We rapidly established an acute PD program. A surgery team placed catheters at the bedside in the intensive care unit; a nephrology team delivered treatment. We provided an alternative to hemodialysis and continuous venovenous hemofiltration for treating patients in the intensive-care unit, demonstrating efficacy with outcomes comparable to standard care. Results:From April 8, 2020 to May 8, 2020, 39 catheters were placed into ten women and 29 men. By June 10, 39% of the patients started on PD recovered kidney function (average ages 56 years for men and 59.5 years for women); men and women who expired were an average 71.8 and 66.2 years old. No episodes of peritonitis were observed; there were nine incidents of minor leaking. Some patients were treated while ventilated in the prone position. Conclusions:Demand compelled us to utilize acute PD during the COVID-19 pandemic. Our experience is one of the largest recently reported in the United States of which we are aware. Acute PD provided lifesaving care to acutely ill patients when expanding current resources was impossible. Our experience may help other programs to avoid rationing dialysis treatments in health crises.

BACKGROUND:Authors have speculated that vascularized composite allotransplantation (VCA) recipients may require greater maintenance immunosuppression than solid organ transplant (SOT) recipients due to the higher antigenicity of skin. However, detailed comparisons of VCA and SOT immunosuppression regimens have been limited. METHODS:Hand and face VCA recipient immunosuppression data were collected through a systematic literature review. Kidney recipient data were obtained through a retrospective chart review of the authors' institution. Prednisone and mycophenolate mofetil (MMF) doses were compared between VCA and kidney recipients at predefined follow-up intervals (<1, 1-5, and >5 y). Tacrolimus target trough levels (TTTL) were compared at follow-up intervals of 1-5 and >5 y, and stratified into our institution's kidney transplant risk-based target ranges (4-6 ng/mL, 6-8 ng/mL) or higher (>8 ng/mL). RESULTS:Immunosuppression data were available for 57 VCA and 98 kidney recipients. There were no significant differences in prednisone doses between groups at all follow-up intervals. VCA recipient mean MMF dose was significantly greater at <1-y (1.71 ± 0.58 versus 1.16 ± 0.55 gm/d; P = 0.01). For VCA recipients, there was a significant difference (P = 0.02) in TTTL distribution over the three predefined therapeutic ranges (4-6 ng/mL, 6-8 ng/mL, and >8 ng/mL) between 1 and 5 y (24.0%, 20.0%, 56.0%, respectively) and >5 y (28.6%, 42.9%, 28.6%). CONCLUSIONS:At longer follow-up, VCA and kidney recipients receive comparable MMF/prednisone doses, and most VCA recipients are treated with TTTL similar to kidney recipients. Further research may improve our understanding of VCA's complex risk/benefit ratio, and enhance informed consent.

Pulmonary disease increases the risk of developing abdominal aortic aneurysms (AAA). However, the mechanism underlying the pathological dialogue between the lungs and aorta is undefined. Here, we find that inflicting acute lung injury (ALI) to mice doubles their incidence of AAA and accelerates macrophage-driven proteolytic damage of the aortic wall. ALI-induced HMGB1 leaks and is captured by arterial macrophages thereby altering their mitochondrial metabolism through RIPK3. RIPK3 promotes mitochondrial fission leading to elevated oxidative stress via DRP1. This triggers MMP12 to lyse arterial matrix, thereby stimulating AAA. Administration of recombinant HMGB1 to WT, but not Ripk3^-/- mice, recapitulates ALI-induced proteolytic collapse of arterial architecture. Deletion of RIPK3 in myeloid cells, DRP1 or MMP12 suppression in ALI-inflicted mice repress arterial stress and brake MMP12 release by transmural macrophages thereby maintaining a strengthened arterial framework refractory to AAA. Our results establish an inter-organ circuitry that alerts arterial macrophages to regulate vascular remodeling.

Anesthetic considerations are integral to the success of facial transplantation (FT), yet limited evidence exists to guide quality improvement. This study presents an institutional anesthesia protocol, defines reported anesthetic considerations, and provides a comprehensive update to inform future directions of the field.

Over 115 000 people are waiting for life-saving organ transplants, of whom a small fraction will receive transplants and many others will die while waiting. Existing efforts to expand the number of available organs, including increasing the number of registered donors and procuring organs in uncontrolled environments, are crucial but unlikely to address the shortage in the near future and will not improve donor/recipient compatibility or organ quality. If successful, organ bioengineering can solve the shortage and improve functional outcomes. Studying manufactured organs in animal models has produced valuable data, but is not sufficient to understand viability in humans. Before risking manufactured organ experimentation in living humans, study of bioengineered organs in recently deceased humans would facilitate evaluation of the function of engineered tissues and the complex interactions between the host and the transplanted tissue. Although such studies do not pose risk to human subjects, they pose unique ethical challenges concerning the previous wishes of the deceased, rights of surviving family members, effective operation and fair distribution of medical services, and public transparency. This article investigates the ethical, legal and social considerations in performing engineered organ research on the recently deceased.

Background: Clinical trials have demonstrated the safety of utilizing hepatitis C viremic donors (HCV+) to expand the donor pool through transplantation into hepatitis C naive recipients (HCV-). However, there has been a lack of enthusiasm to of er HCV+ pancreas grafts to HCV- recipients. We of ered HCV- pancreas patients the option to list for HCV+ donor organs.
Material(s) and Method(s): Patients undergoing pancreas transplant evaluation had informed consent by a transplant physician to receive HCV+ donor organs. We ensured patients had pharmacy coverage for post-transplant HCV anti-retroviral therapy prior to listing. In our early experience, 4 of our 8 transplant recipients elected to list for HCV+ donor organs.
Result(s): In the first 8 months, the average time to transplant from listing was 41 days for patients with standard listing and 21 days for patients listing for HCV+ organs (p<0.05). Of note, 2 of the 4 HCV- recipients were blood type AB and had shorter match time due to their blood type. For all HCV+ donors, COD was anoxia/drug OD, all were HCV antibody and NAT positive, PHS IR, and national imports, with average rank of 3 on the match run. All HCV- donors were local donors with average rank of 21 on the match run. HCV+ donors were younger (28 years) in contrast to HCV- donors (35 years). All recipients have excellent graft function with no signif cant dif erences in complications, LOS, or readmissions.
Conclusion(s): Utilization of HCV+ pancreas donors has allowed our patients increased access to high quality pancreas donors with signif cantly shorter wait times

Objective: Abdominal aortic aneurysm (AAA) is a fatal vascular disease on rupture with still limited mechanistic knowledge of the pathophysiologic process. We sought to determine the heterogeneous cell subtypes and to characterize the spectrum of transcriptome signatures in each cell population within the aneurysmal wall by unbiased single-cell RNA sequencing (scRNA-seq) of human AAA tissue.
Method(s): Aortic specimens were collected from AAA and control healthy organ donor. Samples were processed by enzymatic digestion and mechanical disruption to generate single-cell suspension. Single-cell RNA libraries were prepared after generation of single-cell beads in emulsion. Sequencing was performed on a NovaSeq 6000 platform (Illumina, San Diego, Calif). After alignment, barcode assignment, and sample de-multiplexing, data analysis was performed on t-distributed stochastic neighbor embedding charts of cell transcriptome. Cell clusters were identified by unsupervised proximity based on Euclidian distance and supervised identification of biologic markers within clusters. Pathway analysis algorithms were used to outline biologically relevant networks.
Result(s): Unbiased analysis of scRNA-seq data sets showed 19 different cell clusters with unique transcriptomic signatures in AAA. A total of 8826 significant differentially expressed genes were identified in AAA vs control. Notably, gene transcription-associated extracellular matrix remodeling (COL1A1, COL3A1, COL1A2, LUM), Wnt signaling modulation (SFRP2), and synthetic cellular phenotypes (RPS29, RPS27, RPL13A, RPL28) were among the top increased profiles in AAA tissue. Pathway enrichment analysis of AAA vs control libraries revealed significant modulation of cell proliferation, cell-extracellular matrix interaction, neoangiogenesis, and inflammation. Five novel cell clusters with distinct immune synthetic phenotypes were predominantly abundant in AAA wall compared with the healthy aorta. A robust enrichment in immune cell entities was identified in AAA but not in control tissues, including expansion of CD19⁺ B lymphocytes and a subset of CD3E⁺ T lymphocytes significantly expressing IL32 and CCL5. In contrast, smooth muscle cell (ACTA2⁺MYH11⁺) number declined in AAA but revealed increased transcription of the protease ADAMTS4 and inflammatory signals (CCL19, CCL21, IL6, CCL2). Intercluster pathway analysis revealed enrichment of eukaryotic initiation factor 2 and mechanistic target of rapamycin signaling in the AAA macrophage population along with an increased number of inflammatory and T-cell activation cascades.
Conclusion(s): To the best of our knowledge, this is the first report of scRNA-seq analysis on human AAA. This cutting-edge technique uncovered novel cell clusters and provided a comprehensive understanding of cellular spatiotemporal changes within the AAA wall. Here we provide novel interconnected mechanistic insights into this complex disease to enrich our understanding of AAA development.
Copyright

INTRODUCTION/BACKGROUND:Online resources have become a major source of medical information for the general public. To date, there has not been an assessment of patient-oriented online resources for face and upper extremity transplantation candidates and patients. The goal of this study is to perform a comprehensive assessment of these resources. METHODS:Our analysis relied on 2 dimensions: comprehensiveness and readability. Comprehensiveness was evaluated using 14 predetermined variables. Readability was evaluated using 8 different readability scales through the Readability Studio Professional Edition Software (Oleander Software, Ltd, Vandalia, Ohio). Data were also collected from solid organ transplantation (SOT), specifically kidney and liver, programs for comparison. RESULTS:Face and upper extremity transplantation programs were significantly more likely to list exclusion criteria (73.9% vs 41.2%; P = 0.02), the need for life-long immunosuppression (87.0% vs 58.8%; P = 0.02), and benefits of transplantation (91.3% vs 61.8%; P = 0.01) compared with SOT programs. The average readability level of online resources by all face and upper extremity transplantation programs exceeded the sixth grade reading level recommended by the National Institutes of Health and the American Medical Association. The average reading grade level of online resources by these programs was also significantly higher than those of SOT with both exceeding the recommended reading level (13.95 ± 1.55 vs 12.60 ± 1.65; P = 0.003). CONCLUSIONS:Future efforts in face and upper extremity transplantation should be directed toward developing standardized, comprehensive, and intelligible resources with high-quality content and simple language.