Real-world implementation of normothermic machine perfusion: A detailed analysis of intraoperative and early postoperative impact.

BACKGROUND: Outcome data for the great majority of liver normothermic machine perfusion (NMP) cases derive from the strict confines of clinical trials. Detailed specifics regarding the intraoperative and early postoperative impact of NMP on reperfusion injury and its sequelae during real-world use of this emerging technology remain largely unavailable. METHODS: We analyzed transplants performed in a 3-month pilot period during which surgeons invoked commercial NMP at their discretion. Living donor, multi-organ, and hypothermic machine perfusion transplants were excluded. RESULTS: Intraoperatively, NMP (n = 24) compared to static cold storage (n = 25) recipients required less peri-reperfusion bolus epinephrine (0 vs. 60 µg; p < .001) and post-reperfusion fresh frozen plasma (2.5 vs. 7.0 units; p = .0069), platelets (.0 vs. 2.0 units; p = .042), and hemostatic agents (0% vs. 24%; p = .010). Time from incision to venous reperfusion did not differ (3.6 vs. 3.1; p = .095) but time from venous reperfusion to surgery end was shorter for NMP recipients (2.3 vs. 2.8 h; p = .0045). Postoperatively, NMP recipients required fewer red blood cell (1.0 vs. 4.0 units; p = .0083) and fresh frozen plasma (4.0 vs. 7.0 units; p = .046) transfusions, had shorter intensive care unit stays (33.5 vs. 58.4 h; p = .012), and experienced less early allograft dysfunction according to both the Model for Early Allograft Function Score (3.4 vs. 5.0; p = .0047) and peak AST within 10 days of transplant (619 vs. 1,181 U/L; p = .036). Liver acceptance for the corresponding recipient was conditional on NMP use for 63% (15/24) of cases. CONCLUSION: Real-world NMP use was associated with significantly lower intensity of reperfusion injury and intraoperative and postoperative care that may translate into patient benefit.

A Multi-Modal Approach to Islet and Pancreas Transplantation With Calcineurin-Sparing Immunosuppression Maintains Long-Term Insulin Independence in Patients With Type I Diabetes.

Long-term success in beta-cell replacement remains limited by the toxic effects of calcineurin inhibitors (CNI) on beta-cells and renal function. We report a multi-modal approach including islet and pancreas-after-islet (PAI) transplant utilizing calcineurin-sparing immunosuppression. Ten consecutive non-uremic patients with Type 1 diabetes underwent islet transplant with immunosuppression based on belatacept (BELA; n = 5) or efalizumab (EFA; n = 5). Following islet failure, patients were considered for repeat islet infusion and/or PAI transplant. 70% of patients (four EFA, three BELA) maintained insulin independence at 10 years post-islet transplant, including four patients receiving a single islet infusion and three patients undergoing PAI transplant. 60% remain insulin independent at mean follow-up of 13.3 ± 1.1 years, including one patient 9 years after discontinuing all immunosuppression for adverse events, suggesting operational tolerance. All patients who underwent repeat islet transplant experienced graft failure. Overall, patients demonstrated preserved renal function, with a mild decrease in GFR from 76.5 ± 23.1 mL/min to 50.2 ± 27.1 mL/min (p = 0.192). Patients undergoing PAI showed the greatest degree of renal impairment following initiation of CNI (56% ± 18.7% decrease in GFR). In our series, repeat islet transplant is ineffective at maintaining long-term insulin independence. PAI results in durable insulin independence but is associated with impaired renal function secondary to CNI dependence.

Therapeutic Reasoning: A Conceptual Challenge for Medical Students' Surgical Clerkship.

Issue: Medical students' transition between pre-clinical and clinical environments can be jarring. Unclear expectations, disconnect between the pre-clinical and clinical environments, and feelings of exclusion from the team all negatively influence clerkship experiences. These difficulties are magnified on interventional-based clerkships due to the central role of therapeutic reasoning. Therapeutic reasoning is the process by which clinicians review and select treatments for their patients. Surgical therapeutic reasoning is challenging and infrequently addressed explicitly in the pre-clinical curriculum. This contributes to confusion among medical students as they transition from pre-clinical to clinical learning. Evidence: Multiple studies have identified challenges to medical students' transition to clinical clerkships. Prior authors have outlined numerous barriers to successful medical student integration to clinical teams, including surgical teams. Studies that have assessed students' perceptions of their transition to a clinical setting noted poor understanding of treatment decisions as a source of anxiety. Additionally, of particular importance to medical student team learning is their assimilation into the "communities of clinical practice," groups of healthcare professionals who form teams with which students rotate. Surgeons have distinct approaches to the clinical process compared with non-interventionalists, particularly related to post-diagnostic involvement in care and performing diagnostic workup and treatment concurrently. Knowledge of these approaches is important for integration into surgical teams. Implications: An understanding of interventional therapeutic reasoning is critical to allow for medical students' team integration on surgical and interventional clerkships. By incorporating education involving these concepts during the orientation period prior to students' transition to surgical clerkships, we can help students modify traditional mental frameworks to effectively evaluate, present, and select appropriate interventions for patients. Such education should include a didactic introduction to therapeutic reasoning, interactive discussion with surgeons, and exercises for students to practice skills. This will maximize learning opportunities and clerkship experience.

Motivations and outcomes of compatible living donor-recipient pairs in paired exchange.

Increasing numbers of compatible pairs are choosing to enter paired exchange programs, but motivations, outcomes, and system-level effects of participation are not well described. Using a linkage of the Scientific Registry of Transplant Recipients and National Kidney Registry, we compared outcomes of traditional (originally incompatible) recipients to originally compatible recipients using the Kaplan-Meier method. We identified 154 compatible pairs. Most pairs sought to improve HLA matching. Compared to the original donor, actual donors were younger (39 vs. 50 years, p < .001), less often female (52% vs. 68%, p < .01), higher BMI (27 vs. 25 kg/m², p = .03), less frequently blood type O (36% vs. 80%, p < .001), and had higher eGFR (99 vs. 94 ml/min/1.73 m², p = .02), with a better LKDPI (median 7 vs. 22, p < .001). We observed no differences in graft failure or mortality. Compatible pairs made 280 additional transplants possible, many in highly sensitized recipients with long wait times. Compatible pair recipients derived several benefits from paired exchange, including better donor quality. Living donor pairs should receive counseling regarding all options available, including kidney paired donation. As more compatible pairs choose to enter exchange programs, consideration should be given to optimizing compatible pair and hard-to-transplant recipient outcomes.

Effects of Multi-stage Procurement on the Viability and Function of Human Donor Parathyroid Glands.

INTRODUCTION: Parathyroid allotransplantation is an emerging treatment for severe hypoparathyroidism. Ensuring the viability and functional integrity of donor parathyroid glands following procurement is essential for optimal transplantation outcomes. METHODS: Cellular viability, calcium-responsive hormone secretion, and gland xenograft survival were assessed in a series of deceased donor parathyroid glands following a two-stage procurement procedure recently developed by our group (en bloc cadaveric dissection with subsequent gland isolation after transport to the laboratory). RESULTS: Parathyroid glands resected in this manner and stored up to 48 h in 4°C University of Wisconsin (UW) media retained in vitro viability with no induction of hypoxic stress (HIF-1α) or apoptotic (caspase-3) markers. Ex vivo storage did not significantly affect parathyroid gland calcium sensing capacity, with comparable calcium EC50 values and suppression of parathyroid hormone secretion at high ambient calcium concentrations. The isolated glands engrafted readily, vascularizing rapidly in vivo following transplantation into mice. CONCLUSIONS: Parathyroid tissue retains viability, calcium-sensing capacity, and in vivo engraftment capability after en bloc cadaveric resection, ex vivo dissection, and extended cold storage.

Understanding the Final Disposition of Livers Declined After the Start of Procurement: A Nationwide Organ Procurement Organization Effort.

Declining a liver offer during organ procurement likely increases the risk of discard, but the specifics around late reallocation remain obscure. This voluntarily submitted, prospectively collected data describe late declines and the ultimate disposition of 893 livers. Once a liver suffered an intraoperative decline, only 49% of recovered livers were transplanted. Livers declined ≥80 minutes prior to cross-clamp were transplanted 80% of the time versus livers declined ≥80 minutes after cross-clamp, which were transplanted 45% of the time. The final disposition of these livers was into a predetermined backup patient (51%) or required an out-of-sequence expedited allocation (42%). Prerecovery imaging and prerecovery biopsy did not influence the ability to reallocate a liver, and livers from donors after circulatory death are rarely successfully reallocated. In conclusion, this study begins to shed light on this seemingly common practice. A total of 85% of centers had an intraoperative decline, but 4% of centers accounted for 25% of the declines. Organ procurement organizations often enter expedited liver allocation, and instituting a cross-clamp delay to allow for reallocation may influence the disposition of these liver grafts. Expedited allocation was more time consuming than allocation into a predetermined backup. Although a certain number of intraoperative declines probably suggests a healthy amount of donor selection aggressiveness at the time of the initial organ offer, the 47% risk of discard of livers declined intraoperatively suggests that United Network for Organ Sharing should consider systematically collecting data about intraoperative declines so we can learn more about this event that influences organ utilization.

Long-term follow-up of beta cell replacement therapy in 10 HIV-infected patients with renal failure secondary to type 1 diabetes mellitus.

The approach to transplantation in human immunodeficiency virus (HIV)-positive patients has been conservative due to fear of exacerbating an immunocompromised condition. As a result, HIV-positive patients with diabetes were initially excluded from beta cell replacement therapy. Early reports of pancreas transplant in patients with HIV described high rates of early graft loss with limited follow-up. We report long-term follow-up of islet or pancreas transplantation in HIV-positive type 1 diabetic patients who received a kidney transplant concurrently or had previously undergone kidney transplantation. Although 4 patients developed polyoma viremia, highly active antiretroviral therapy and adequate infectious prophylaxis were successful in providing protection until CD4+ counts recovered. Coordination with HIV providers is critical to reduce the risk of rejection by minimizing drug-drug interactions. Also, protocols for prophylaxis of opportunistic infections and strategies for monitoring and treating BK viremia are important given the degree of immunosuppression required. This series demonstrates that type 1 diabetic patients with well-controlled HIV and renal failure can be appropriate candidates for beta cell replacement, with a low rate of infectious complications, early graft loss, and rejection, so excellent long-term graft survival is possible. Additionally, patients with HIV and cardiovascular contraindications can undergo islet infusion.

Outcomes of arterial bypass preceding resection of retroperitoneal masses involving major vessels.

BACKGROUND: Current surgical management of retroperitoneal masses involving major vessels now includes complete en bloc resection with in situ venous, arterial, or combined reconstruction. No studies have investigated preresection arterial bypass for continuous lower extremity perfusion during definitive resection. Here, we characterize and compare the outcomes of surgery for retroperitoneal masses with major vascular involvement by a two-stage approach (femoral-femoral bypass preceding resection) and the traditional one-stage approach (consecutive resection and in situ vascular reconstruction). MATERIALS AND METHODS: We retrospectively reviewed patients who underwent resection of retroperitoneal masses and reconstruction of major arterial or venous structures from 2004 to 2016. Outcomes were compared with unpaired t-tests, chi-squared tests, and Kaplan-Meier analysis. RESULTS: Eight patients underwent a two-stage procedure, and seven underwent a one-stage procedure for retroperitoneal masses with vascular involvement. Mean (±SD) oncologic resection time (443 ± 215 versus 648 ± 128 min, P = 0.047) and postoperative ICU stay (0.9 ± 1.3 versus 4.4 ± 2.9 d, P = 0.018) were significantly shorter for the two-stage approach. CONCLUSIONS: To our knowledge, this is the first report of a two-stage approach for resection of retroperitoneal masses with major vessel involvement. Femoral-femoral arterial bypass before definitive resection could be a viable option for improving intraoperative vascular control and decreasing perioperative complications in these complex procedures.

Missing the Match: A National Survey Investigating Education in Renal Donor-Recipient Matching.

PURPOSE: Clinical judgment in renal donor organ and recipient selection is gained through fellowship and mentorship in early career. We aim to understand the past and current state of organ acceptance education. METHODS: We developed and distributed an anonymous, national survey to American Society of Transplant Surgeons faculty members and transplant surgery fellows in 2022. Survey questions explored in detail the evaluation of organ offers, the extent of formal education in organ evaluation, and attitudes regarding training adequacy. FINDINGS: Ninety-eight attending surgeons (65 men, 25 women, and 3 nonbinary) and 38 fellows (25 men, 6 women, and 2 nonbinary) responded. Seventy-eight percent of attending surgeons and 6% of fellows take primary organ offers. Forty-four percent of fellows report no didactic education in donor evaluation and recipient selection. Fellows report that discussion with attending surgeons (37.2%) and independent study of the literature (35.4%) are their primary modes of learning. Fellows call for additional clinical decision-making experience (47.3%), further didactic sessions (44.7%), and additional discussions with faculty (44.7%). Sixty-four percent of fellows and 55% of attendings felt their training provided adequate education about donor selection. CONCLUSION: Our responses suggest gaps in education regarding donor and recipient selection. Increased clinical experience and standardized education at the national level represent opportunities for improvement.

Assessment of the financial implications for laparoscopic liver surgery: a single-centre UK cost analysis for minor and major hepatectomy.

BACKGROUND: Laparoscopic hepatectomy is progressively gaining popularity. However, it is still unclear whether the laparoscopic approach offers cost advantages compared with the open approach, especially when major hepatectomies are required. Data providing useful insights into the costs of the laparoscopic approach for clinicians and hospitals are needed. The aim of this study is to assess the financial implications of the laparoscopic approach for two standardized minor and major hepatectomies: left lateral sectionectomy and right hepatectomy. METHODS: A cost comparison analysis of patients undergoing laparoscopic right hepatectomy (LRH) and laparoscopic left lateral sectionectomy (LLLS) versus the open counterparts was performed. Data considered for the comparison analysis were operative costs (theatre cost, consumables and surgeon/anaesthetic labour cost), postoperative costs (hospital stay, complication management and readmissions) and overall costs. RESULTS: A total of 149 patients were included: 38 patients underwent LRH and 46 open right hepatectomy (ORH); 46 patients underwent LLLS and 19 open left lateral sectionectomy (OLLS). For LRH the mean operative, postoperative and overall costs were £10,181, £4,037 and £14,218; for ORH the mean operative, postoperative and overall costs were £6,483 (p < 0.0001), £10,304 (p < 0.0001) and £16,787 (p = 0.886). Regarding LLLS, the mean operative, postoperative and overall costs were £5,460, £2,599 and £8,059; for OLLS the mean operative, postoperative and overall costs were £5,841 (p = 0.874), £5,796 (p < 0.0001) and £11,637 (p = 0.0001). CONCLUSION: Our data support the cost advantage of the laparoscopic approach for left lateral sectionectomy and the cost neutrality for right hepatectomy.

Resected Tumor Outcome and Recurrence (RESTORE) Index for Hepatocellular Carcinoma Recurrence after Resection.

Hepatocellular carcinoma (HCC) is the most common primary liver cancer and the fourth most common cause of cancer-related death worldwide [...].

Robotic training for medical students: feasibility of a pilot simulation curriculum.

While robotic procedures are growing rapidly, medical students have a limited role in robotic surgeries. Curricula are needed to enhance engagement. We examined feasibility of augmenting Intuitive Surgical (IS) robotic training for medical students. As a pilot, 18 senior students accepted an invitation to a simulation course with a daVinci robot trainer. Course teaching objectives included introducing robotic features, functionalities, and roles. A 1-h online module from the IS learning platform and a 4-h in-person session comprised the course. The in-person session included an overview of the robot by an IS trainer (1.5 h), skills practice at console (1.5 h), and a simulation exercise focused on the bedside assist role (1 h). Feasibility included assessing implementation and acceptability using a post-session survey and focus group (FG). Survey responses were compiled. FG transcripts were analyzed using inductive thematic analysis techniques. Fourteen students participated. Implementation was successful as interested students signed up and completed each of the course components. Regarding acceptability, students reported the training valuable and recommended it as preparation for robotic cases during core clerkships and sub-internships. In addition, FGs revealed 4 themes: (1) perceived expectations of students in the OR; (2) OR vs. outside-OR learning; (3) simulation of stress; and (4) opportunities to improve the simulation component. To increase preparation for the robotic OR and shift robotic training earlier in the surgical education continuum, educators should consider hands-on simulation for medical students. We demonstrate feasibility although logistics may limit scalability for large numbers of students.

Number of Local Regional Therapies for Hepatocellular Carcinoma and Peri-Operative Outcomes after Liver Transplantation.

The wait times for patients with hepatocellular carcinoma (HCC) listed for liver transplant are longer than ever, which has led to an increased reliance on the use of pre-operative LRTs. The impact that multiple rounds of LRTs have on peri-operative outcomes following transplant is unknown. This was a retrospective single center analysis of 298 consecutive patients with HCC who underwent liver transplant (January 2017 to May 2021). The data was obtained from two institution-specific databases and the TransQIP database. Of the 298 patients, 27 (9.1%) underwent no LRTs, 156 (52.4%) underwent 1-2 LRTs, and 115 (38.6%) underwent ≥3 LRTs prior to LT. The patients with ≥3 LRTs had a significantly higher rate of bile leak compared to patients who received 1-2 LRTs (7.0 vs. 1.3%, p = 0.014). Unadjusted and adjusted regression analyses demonstrated a significant association between the total number of LRTs administered and bile leak, but not rates of overall biliary complications. The total number of LRTs was not significantly associated with any other peri-operative or post-operative outcome measure. These findings support the aggressive use of LRTs to control HCC in patients awaiting liver transplant, with further evaluation needed to confirm the biliary leak findings.

Confronting new challenges: Faculty perceptions of gaps in current laparoscopic curricula in a changing training landscape.

Background: Opportunities for residents to develop laparoscopic skills have decreased with the rise in robotic operations and the development of complex, subspecialized laparoscopic operations. Given the changing training landscape, this study aimed to identify laparoscopic surgeons' perceptions of gaps in current laparoscopic skills in general surgery, obstetrics-gynecology, and urology residency programs. Methods: Laparoscopic surgeons who operate with residents participated in semi-structured interviews. Questions addressed expectations for resident proficiency, deficits in laparoscopic surgical skills, and barriers to learning and teaching. Two authors independently coded de-identified transcripts followed by a conventional content analysis. Results: Fourteen faculty members from thirteen subspecialties participated. Faculty identified three main areas to improve laparoscopic training across specialties: foundational knowledge, technical skills, and cognitive skills. They also recognized an overarching opportunity to address faculty development. Conclusions: This qualitative study highlighted key deficiencies in laparoscopic training that have emerged in the current, changing era of minimally invasive surgery. Key message: This qualitative study identified laparoscopic educators' perceptions of deficiencies in laparoscopic training. Findings emphasized the importance of incorporating high quality educational practices to optimize training in the current changing landscape of laparoscopic surgery.

Steroid Avoidance After Adult Living Donor Liver Transplant: A Cohort Analysis.

Although steroid avoidance (SA) has been studied in deceased donor liver transplant, little is known about SA in living donor liver transplant (LDLT). We report the characteristics and outcomes, including the incidence of early acute rejection (AR) and complications of steroid use, in 2 cohorts of LDLT recipients. Methods: Routine steroid maintenance (SM) after LDLT was stopped in December 2017. Our single-center retrospective cohort study spans 2 eras. Two hundred forty-two adult recipients underwent LDLT with SM (January 2000-December 2017), and 83 adult recipients (December 2017-August 2021) underwent LDLT with SA. Early AR was defined as a biopsy showing pathologic characteristics within 6 mo after LDLT. Univariate and multivariate logistic regressions were performed to evaluate the effects of relevant recipient and donor characteristics on the incidence of early AR in our cohort. Results: Neither the difference in early AR rate between cohorts (SA 19/83 [22.9%] versus SM 41/242 [17%]; P = 0.46) nor a subset analysis of patients with autoimmune disease (SA 5/17 [29.4%] versus SM 19/58 [22.4%]; P = 0.71) reached statistical significance. Univariate and multivariate logistic regressions for early AR identified recipient age to be a statistically significant risk factor (P < 0.001). Of the patients without diabetes before LDLT, 3 of 56 (5.4%) on SA versus 26 of 200 (13%) on SM needed medications prescribed for glucose control at the time of discharge (P = 0.11). Patient survival was similar between SA and SM cohorts (SA 94% versus SM 91%, P = 0.34) 3 y after transplant. Conclusions: LDLT recipients treated with SA do not exhibit significantly higher rates of rejection or increased mortality than patients treated with SM. Notably, this result is similar for recipients with autoimmune disease.

DCD liver transplant in patients with a MELD over 35.

Introduction: Donation after circulatory death (DCD) liver transplantation (LT) makes up well less than 1% of all LTs with a Model for End-Stage Liver Disease (MELD)≥35 in the United States. We hypothesized DCD-LT yields acceptable ischemia-reperfusion and reasonable outcomes for recipients with MELD≥35. Methods: We analyzed recipients with lab-MELD≥35 at transplant within the UCSF (n=41) and the UNOS (n=375) cohorts using multivariate Cox regression and propensity score matching. Results: In the UCSF cohort, five-year patient survival was 85% for DCD-LTs and 86% for matched-Donation after Brain Death donors-(DBD) LTs (p=0.843). Multivariate analyses showed that younger donor/recipient age and more recent transplants (2011-2021 versus 1999-2010) were associated with better survival. DCD vs. DBD graft use did not significantly impact survival (HR: 1.2, 95%CI 0.6-2.7). The transaminase peak was approximately doubled, indicating suggesting an increased ischemia-reperfusion hit. DCD-LTs had a median post-LT length of stay of 11 days, and 34% (14/41) were on dialysis at discharge versus 12 days and 22% (9/41) for DBD-LTs. 27% (11/41) DCD-LTs versus 12% (5/41) DBD-LTs developed a biliary complication (p=0.095). UNOS cohort analysis confirmed patient survival predictors, but DCD graft emerged as a risk factor (HR: 1.5, 95%CI 1.3-1.9) with five-year patient survival of 65% versus 75% for DBD-LTs (p=0.016). This difference became non-significant in a sub-analysis focusing on MELD 35-36 recipients. Analysis of MELD≥35 DCD recipients showed that donor age of <30yo independently reduced the risk of graft loss by 30% (HR, 95%CI: 0.7 (0.9-0.5), p=0.019). Retransplant status was associated with a doubled risk of adverse event (HR, 95%CI: 2.1 (1.4-3.3), p=0.001). The rejection rates at 1y were similar between DCD- and DBD-LTs, (9.3% (35/375) versus 1,541 (8.7% (1,541/17,677), respectively). Discussion: In highly selected recipient/donor pair, DCD transplantation is feasible and can achieve comparable survival to DBD transplantation. Biliary complications occurred at the expected rates. In the absence of selection, DCD-LTs outcomes remain worse than those of DBD-LTs.

Machine learning to predict waitlist dropout among liver transplant candidates with hepatocellular carcinoma.

BACKGROUND: Accurate prediction of outcome among liver transplant candidates with hepatocellular carcinoma (HCC) remains challenging. We developed a prediction model for waitlist dropout among liver transplant candidates with HCC. METHODS: The study included 18,920 adult liver transplant candidates in the United States listed with a diagnosis of HCC, with data provided by the Organ Procurement and Transplantation Network. The primary outcomes were 3-, 6-, and 12-month waitlist dropout, defined as removal from the liver transplant waitlist due to death or clinical deterioration. RESULTS: Using 1,181 unique variables, the random forest model and Spearman's correlation analyses converged on 12 predictive features involving 5 variables, including AFP (maximum and average), largest tumor size (minimum, average, and most recent), bilirubin (minimum and average), INR (minimum and average), and ascites (maximum, average, and most recent). The final Cox proportional hazards model had a concordance statistic of 0.74 in the validation set. An online calculator was created for clinical use and can be found at: http://hcclivercalc.cloudmedxhealth.com/. CONCLUSION: In summary, a simple, interpretable 5-variable model predicted 3-, 6-, and 12-month waitlist dropout among patients with HCC. This prediction can be used to appropriately prioritize patients with HCC and their imminent need for transplant.