Portable hypothermic oxygenated machine perfusion for organ preservation in liver transplantation: A randomized, open-label, clinical trial.

BACKGROUND AND AIMS: In liver transplantation, cold preservation induces ischemia, resulting in significant reperfusion injury. Hypothermic oxygenated machine perfusion (HMP-O 2 ) has shown benefits compared to static cold storage (SCS) by limiting ischemia-reperfusion injury. This study reports outcomes using a novel portable HMP-O 2 device in the first US randomized control trial. APPROACH AND RESULTS: The PILOT trial (NCT03484455) was a multicenter, randomized, open-label, noninferiority trial, with participants randomized to HMP-O 2 or SCS. HMP-O 2 livers were preserved using the Lifeport Liver Transporter and Vasosol perfusion solution. The primary outcome was early allograft dysfunction. Noninferiority margin was 7.5%. From April 3, 2019, to July 12, 2022, 179 patients were randomized to HMP-O 2 (n=90) or SCS (n=89). The per-protocol cohort included 63 HMP-O 2 and 73 SCS. Early allograft dysfunction occurred in 11.1% HMP-O 2 (N=7) and 16.4% SCS (N=12). The risk difference between HMP-O 2 and SCS was -5.33% (one-sided 95% upper confidence limit of 5.81%), establishing noninferiority. The risk of graft failure as predicted by Liver Graft Assessment Following Transplant score at seven days (L-GrAFT 7 ) was lower with HMP-O 2 [median (IQR) 3.4% (2.4-6.5) vs. 4.5% (2.9-9.4), p =0.024]. Primary nonfunction occurred in 2.2% of all SCS (n=3, p =0.10). Biliary strictures occurred in 16.4% SCS (n=12) and 6.3% (n=4) HMP-O 2 ( p =0.18). Nonanastomotic biliary strictures occurred only in SCS (n=4). CONCLUSIONS: HMP-O 2 demonstrates safety and noninferior efficacy for liver graft preservation in comparison to SCS. Early allograft failure by L-GrAFT 7 was lower in HMP-O 2 , suggesting improved early clinical function. Recipients of HMP-O 2 livers also demonstrated a lower incidence of primary nonfunction and biliary strictures, although this difference did not reach significance.

Living Donor Liver Transplantation for Hepatocellular Carcinoma Within and Outside Traditional Selection Criteria: A Multicentric North American Experience.

OBJECTIVE: To evaluate long-term oncologic outcomes of patients post-living donor liver transplantation (LDLT) within and outside standard transplantation selection criteria and the added value of the incorporation of the New York-California (NYCA) score. BACKGROUND: LDLT offers an opportunity to decrease the liver transplantation waitlist, reduce waitlist mortality, and expand selection criteria for patients with hepatocellular carcinoma (HCC). METHODS: Primary adult LDLT recipients between October 1999 and August 2019 were identified from a multicenter cohort of 12 North American centers. Posttransplantation and recurrence-free survival were evaluated using the Kaplan-Meier method. RESULTS: Three hundred sixty LDLTs were identified. Patients within Milan criteria (MC) at transplantation had a 1, 5, and 10-year posttransplantation survival of 90.9%, 78.5%, and 64.1% versus outside MC 90.4%, 68.6%, and 57.7% ( P = 0.20), respectively. For patients within the University of California San Francisco (UCSF) criteria, respective posttransplantation survival was 90.6%, 77.8%, and 65.0%, versus outside UCSF 92.1%, 63.8%, and 45.8% ( P = 0.08). Fifty-three (83%) patients classified as outside MC at transplantation would have been classified as either low or acceptable risk with the NYCA score. These patients had a 5-year overall survival of 72.2%. Similarly, 28(80%) patients classified as outside UCSF at transplantation would have been classified as a low or acceptable risk with a 5-year overall survival of 65.3%. CONCLUSIONS: Long-term survival is excellent for patients with HCC undergoing LDLT within and outside selection criteria, exceeding the minimum recommended 5-year rate of 60% proposed by consensus guidelines. The NYCA categorization offers insight into identifying a substantial proportion of patients with HCC outside the MC and the UCSF criteria who still achieve similar post-LDLT outcomes as patients within the criteria.

Liver Histology Predicts Liver Regeneration and Outcome in ALPPS: Novel Findings From A Multicenter Study.

BACKGROUND AND AIMS: Alterations in liver histology influence the liver's capacity to regenerate, but the relevance of each of the different changes in rapid liver growth induction is unknown. This study aimed to analyze the influence of the degree of histological alterations during the first and second stages on the ability of the liver to regenerate. METHODS: This cohort study included data obtained from the International ALPPS Registry between November 2011 and October 2020. Only patients with colorectal liver metastases were included in the study. We developed a histological risk score based on histological changes (stages 1 and 2) and a tumor pathology score based on the histological factors associated with poor tumor prognosis. RESULTS: In total, 395 patients were included. The time to reach stage 2 was shorter in patients with a low histological risk stage 1 (13 vs 17 days, P ˂0.01), low histological risk stage 2 (13 vs 15 days, P <0.01), and low pathological tumor risk (13 vs 15 days, P <0.01). Regarding interval stage, there was a higher inverse correlation in high histological risk stage 1 group compared to low histological risk 1 group in relation with future liver remnant body weight ( r =-0.1 and r =-0.08, respectively), and future liver remnant ( r =-0.15 and r =-0.06, respectively). CONCLUSIONS: ALPPS is associated with increased histological alterations in the liver parenchyma. It seems that the more histological alterations present and the higher the number of poor prognostic factors in the tumor histology, the longer the time to reach the second stage.

Harmonizing Definitions and Perspectives in Extreme Liver Surgery: A Delphi Experts Consensus.

OBJECTIVE: To propose to our community a common language about extreme liver surgery. BACKGROUND: The lack of a clear definition of extreme liver surgery prevents convincing comparisons of results among centers. METHODS: We used a two-round Delphi methodology to quantify consensus among liver surgery experts. For inclusion in the final recommendations, we established a consensus when the positive responses (agree and totally agree) exceeded 70%. The study steering group summarized and reported the recommendations. In general, a five-point Likert scale with a neutral central value was used, and in a few cases multiple choices. Results are displayed as numbers and percentages. RESULTS: A two-round Delphi study was completed by 38 expert surgeons in complex hepatobiliary surgery. The surgeon´s median age was 58 years old (52-63) and the median years of experience was 25 years (20-31). For the proposed definitions of total vascular occlusion, hepatic flow occlusion and inferior vein occlusion, the degree of agreement was 97%, 81% and 84%, respectively. In situ approach (64%) was the preferred, followed by ante situ (22%) and ex situ (14%). Autologous or cadaveric graft for hepatic artery or hepatic vein repair were the most recommended (89%). The use of veno-venous bypass or portocaval shunt revealed the divergence depending on the case. Overall, 75% of the experts agreed with the proposed definition for extreme liver surgery. CONCLUSION: Obtaining a consensus on the definition of extreme liver surgery is essential to guarantee the correct management of patients with highly complex hepatobiliary oncological disease. The management of candidates for extreme liver surgery involves comprehensive care ranging from adequate patient selection to the appropriate surgical strategy.

Update to 'A Contemporary Systematic Review on Liver Transplantation for Unresectable Liver Metastasis of Colorectal Cancer'.

Colorectal cancer is the second most common cause of cancer-related death worldwide, and half of patients present with colorectal liver metastasis (CRLM). Liver transplant (LT) has emerged as a treatment modality for otherwise unresectable CRLM. Since the publication of the Lebeck-Lee systematic review in 2022, additional evidence has come to light supporting LT for CRLM in highly selected patients. This includes reports of >10-year follow-up with over 80% survival rates in low-risk patients. As these updated reports have significantly changed our collective knowledge, this article is intended to serve as an update to the 2022 systematic review to include the most up-to-date evidence on the subject.

The High Incidence of Occult Carcinoma in Total Hepatectomy Specimens of Patients Treated for Unresectable Colorectal Liver Metastases With Liver Transplant.

OBJECTIVE: To describe the rate of occult carcinoma deposits in total hepatectomy specimens from patients treated with liver transplant (LT) for colorectal liver metastases (CRLM). BACKGROUND: Previous studies have shown that patients with CRLM treated with systemic therapy demonstrate a high rate of complete radiographic response or may have disappearing liver metastases. However, this does not necessarily translate into a complete pathologic response, and residual invasive cancer may be found in up to 80% of the disappearing tumors after resection. METHODS: Retrospective review of 14 patients who underwent LT for CRLM, at 2 centers. Radiographic and pathologic correlation of the number of tumors and their viability before and after LT was performed. RESULTS: The median (interquartile range) number of tumors at diagnosis was 11 (4-23). The median number of chemotherapy cycles was 24 (16-37). Hepatic artery infusion was used in 5 patients (35.7%); 6 (42.9%) underwent surgical resection, and 5 (35.7%) received locoregional therapy. The indication for LT was unresectability in 8 patients (57.1%) and liver failure secondary to oncologic treatment in the remaining 6 (42.9%). Before LT, 7 patients (50%) demonstrated fluorodeoxyglucose-avid tumors and 7 (50%) had a complete radiographic response. Histopathologically, 11 patients (78.6%) had a viable tumor. Nine (64.2%) of the 14 patients were found to have undiagnosed metastases on explant pathology, with at least 22 unaccounted viable tumors before LT. Furthermore, 4 (57.1%) of the 7 patients who demonstrated complete radiographic response harbored viable carcinoma on explant pathology. CONCLUSIONS: A complete radiographic response does not reliably predict a complete pathologic response. In patients with unresectable CRLM, total hepatectomy and LT represent a promising treatment options to prevent indolent disease progression from disappearing CRLM.

The Current State of Liver Transplantation for Colorectal Liver Metastases in the United States: A Call for Standardized Reporting.

BACKGROUND: Current success in transplant oncology for select liver tumors, such as hepatocellular carcinoma, has ignited international interest in liver transplantation (LT) as a therapeutic option for nonresectable colorectal liver metastases (CRLM). In the United States, the CRLM LT experience is limited to reports from a handful of centers. This study was designed to summarize donor, recipient, and transplant center characteristics and posttransplant outcomes for the indication of CRLM. METHODS: Adult, primary LT patients listed between December 2017 and March 2022 were identified by using United Network Organ Sharing database. LT for CRLM was identified from variables: "DIAG_OSTXT"; "DGN_OSTXT_TCR"; "DGN2_OSTXT_TCR"; and "MALIG_TY_OSTXT." RESULTS: During this study period, 64 patients were listed, and 46 received LT for CRLM in 15 centers. Of 46 patients who underwent LT for CRLM, 26 patients (56.5%) received LTs using living donor LT (LDLT), and 20 patients received LT using deceased donor (DDLT) (43.5%). The median laboratory MELD-Na score at the time of listing was statistically similar between the LDLT and DDLT groups (8 vs. 9, P = 0.14). This persisted at the time of LT (8 vs. 12, P = 0.06). The 1-, 2-, and 3-year, disease-free, survival rates were 75.1, 53.7, and 53.7%. Overall survival rates were 89.0, 60.4, and 60.4%, respectively. CONCLUSIONS: This first comprehensive U.S. analysis of LT for CRLM suggests a burgeoning interest in high-volume U.S. transplant centers. Strategies to optimize patient selection are limited by the scarce oncologic history provided in UNOS data, warranting a separate registry to study LT in CRLM.

Longitudinal incremental propensity score interventions for limited resource settings.

Many real-life treatments are of limited supply and cannot be provided to all individuals in the population. For example, patients on the liver transplant waiting list usually cannot be assigned a liver transplant immediately at the time they reach highest priority because a suitable organ is not immediately available. In settings with limited supply, investigators are often interested in the effects of treatment strategies in which a limited proportion of patients receive an organ at a given time, that is, treatment regimes satisfying resource constraints. Here, we describe an estimand that allows us to define causal effects of treatment strategies that satisfy resource constraints: incremental propensity score interventions (IPSIs) for limited resources. IPSIs flexibly constrain time-varying resource utilization through proportional scaling of patients' natural propensities for treatment, thereby preserving existing propensity rank ordering compared to the status quo. We derive a simple class of inverse-probability-weighted estimators, and we apply one such estimator to evaluate the effect of restricting or expanding utilization of "increased risk" liver organs to treat patients with end-stage liver disease.

Liver transplantation for unresectable colorectal liver metastasis.

PURPOSE OF REVIEW: To summarize the current state of liver transplantation (LT) for unresectable colorectal liver metastases (uCRLM), and to address future directions. RECENT FINDINGS: The Norwegian secondary cancer (SECA) I and SECA II studies demonstrated that after LT the 5-year survival of a highly selected group of patients with uCRLM could be as high as 60% and 83%, respectively. After long-term follow-up, the 5- and 10-year survival was shown to be 43% and 26%, respectively. Furthermore, data has accumulated in other countries and a North American study reported a 1.5-year survival of 100%. In addition, steady growth has been demonstrated in the US, with 46 patients transplanted to date and 19 centers enrolling patients for this indication. Lastly, although recurrence is almost universal in patients with a high tumor burden, it has not been an accurate surrogate for survival, reflecting the relatively indolent nature of recurrence after LT. SUMMARY: Growing evidence has shown that excellent survival and even cure can be achieved in highly selected patients with uCRLM, with survival rates far superior than in patients treated with chemotherapy. The next step is to create national registries to standardize selection criteria and establish the optimal approach and best practices for incorporating LT for uCRLM into the treatment armamentarium.

GM-CSF drives myelopoiesis, recruitment and polarisation of tumour-associated macrophages in cholangiocarcinoma and systemic blockade facilitates antitumour immunity.

OBJECTIVE: Intrahepatic cholangiocarcinoma (iCCA) is rising in incidence, and at present, there are limited effective systemic therapies. iCCA tumours are infiltrated by stromal cells, with high prevalence of suppressive myeloid populations including tumour-associated macrophages (TAMs) and myeloid-derived suppressor cells (MDSCs). Here, we show that tumour-derived granulocyte-macrophage colony-stimulating factor (GM-CSF) and the host bone marrow is central for monopoiesis and potentiation of TAMs, and abrogation of this signalling axis facilitates antitumour immunity in a novel model of iCCA. METHODS: Blood and tumours were analysed from iCCA patients and controls. Treatment and correlative studies were performed in mice with autochthonous and established orthotopic iCCA tumours treated with anti-GM-CSF monoclonal antibody. RESULTS: Systemic elevation in circulating myeloid cells correlates with poor prognosis in patients with iCCA, and patients who undergo resection have a worse overall survival if tumours are more infiltrated with CD68+ TAMs. Mice with spontaneous iCCA demonstrate significant elevation of monocytic myeloid cells in the tumour microenvironment and immune compartments, and tumours overexpress GM-CSF. Blockade of GM-CSF with a monoclonal antibody decreased tumour growth and spread. Mice bearing orthotopic tumours treated with anti-GM-CSF demonstrate repolarisation of immunosuppressive TAMs and MDSCs, facilitating T cell response and tumour regression. GM-CSF blockade dampened inflammatory gene networks in tumours and TAMs. Human tumours with decreased GM-CSF expression exhibit improved overall survival after resection. CONCLUSIONS: iCCA uses the GM-CSF-bone marrow axis to establish an immunosuppressive tumour microenvironment. Blockade of the GM-CSF axis promotes antitumour T cell immunity.

A multicentre outcome analysis to define global benchmarks for donation after circulatory death liver transplantation.

BACKGROUND & AIMS: The concept of benchmarking is established in the field of transplant surgery; however, benchmark values for donation after circulatory death (DCD) liver transplantation are not available. Thus, we aimed to identify the best possible outcomes in DCD liver transplantation and to propose outcome reference values. METHODS: Based on 2,219 controlled DCD liver transplantations, collected from 17 centres in North America and Europe, we identified 1,012 low-risk, primary, adult liver transplantations with a laboratory MELD score of ≤20 points, receiving a DCD liver with a total donor warm ischemia time of ≤30 minutes and asystolic donor warm ischemia time of ≤15 minutes. Clinically relevant outcomes were selected and complications were reported according to the Clavien-Dindo-Grading and the comprehensive complication index (CCI). Corresponding benchmark cut-offs were based on median values of each centre, where the 75th-percentile was considered. RESULTS: Benchmark cases represented between 19.7% and 75% of DCD transplantations in participating centres. The 1-year retransplant and mortality rates were 4.5% and 8.4% in the benchmark group, respectively. Within the first year of follow-up, 51.1% of recipients developed at least 1 major complication (≥Clavien-Dindo-Grade III). Benchmark cut-offs were ≤3 days and ≤16 days for ICU and hospital stay, ≤66% for severe recipient complications (≥Grade III), ≤16.8% for ischemic cholangiopathy, and ≤38.9 CCI points 1 year after transplant. Comparisons with higher risk groups showed more complications and impaired graft survival outside the benchmark cut-offs. Organ perfusion techniques reduced the complications to values below benchmark cut-offs, despite higher graft risk. CONCLUSIONS: Despite excellent 1-year survival, morbidity in benchmark cases remains high. Benchmark cut-offs targeting morbidity parameters offer a valid tool to assess the protective value of new preservation technologies in higher risk groups and to provide a valid comparator cohort for future clinical trials. LAY SUMMARY: The best possible outcomes after liver transplantation of grafts donated after circulatory death (DCD) were defined using the concept of benchmarking. These were based on 2,219 liver transplantations following controlled DCD donation in 17 centres worldwide. Donor and recipient combinations with higher risk had significantly worse outcomes. However, the use of novel organ perfusion technology helped high-risk patients achieve similar outcomes as the benchmark cohort.

Sex Disparities in Outcomes Following Major Liver Surgery: New Powers of Estrogen?

AIM: To explore potential sex differences in outcomes and regenerative parameters post major hepatectomies. BACKGROUND: Although controversial, sex differences in liver regeneration have been reported for animals. Whether sex disparity exists in human liver regeneration is unknown. METHODS: Data from consecutive hepatectomy patients (55 females, 67 males) and from the international ALPPS (Associating-Liver-Partition-and-Portal-vein-ligation-for-Staged-hepatectomy, a two stage hepatectomy) registry (449 females, 729 males) were analyzed. Endpoints were severe morbidity (≥3b Clavien-Dindo grades), Model for End-stage Liver Disease (MELD) scores, and ALPPS interstage intervals. For validation and mechanistic insight, female-male ALPSS mouse models were established. t , χ 2 , or Mann-Whitney tests were used for comparisons. Univariate/multivariate analyses were performed with sensitivity inclusion. RESULTS: Following major hepatectomy (Hx), males had more severe complications ( P =0.03) and higher liver dysfunction (MELD) P =0.0001) than females. Multivariate analysis established male sex as a predictor of complications after ALPPS stage 1 (odds ratio=1.78; 95% confidence interval: 1.126-2.89; P =0.01), and of enhanced liver dysfunction after stage 2 (odds ratio=1.93; 95% confidence interval: 1.01-3.69; P =0.045). Female patients displayed shorter interstage intervals (<2 weeks, 64% females versus 56% males, P =0.01), however, not in postmenopausal subgroups. In mice, females regenerated faster than males after ALPPS stage 1, an effect that was lost upon estrogen antagonism. CONCLUSIONS: Poorer outcomes after major surgery in males and shorter ALPPS interstage intervals in females not necessarily suggest a superior regenerative capacity of female liver. The loss of interstage advantages in postmenopausal women and the mouse experiments point to estrogen as the driver behind these sex disparities. Estrogen's benefits call for an assessment in postmenopausal women, and perhaps men, undergoing major liver surgery.

Novel Benchmark Values for Redo Liver Transplantation: Does the Outcome Justify the Effort?

OBJECTIVE: To define benchmark cutoffs for redo liver transplantation (redo-LT). BACKGROUND: In the era of organ shortage, redo-LT is frequently discussed in terms of expected poor outcome and wasteful resources. However, there is a lack of benchmark data to reliably evaluate outcomes after redo-LT. METHODS: We collected data on redo-LT between January 2010 and December 2018 from 22 high-volume transplant centers. Benchmark cases were defined as recipients with model of end stage liver disease (MELD) score ≤25, absence of portal vein thrombosis, no mechanical ventilation at the time of surgery, receiving a graft from a donor after brain death. Also, high-urgent priority and early redo-LT including those for primary nonfunction (PNF) or hepatic artery thrombosis were excluded. Benchmark cutoffs were derived from the 75th percentile of the medians of all benchmark centers. RESULTS: Of 1110 redo-LT, 373 (34%) cases qualified as benchmark cases. Among these cases, the rate of postoperative complications until discharge was 76%, and increased up to 87% at 1-year, respectively. One-year overall survival rate was excellent with 90%. Benchmark cutoffs included Comprehensive Complication Index CCI ® at 1-year of ≤72, and in-hospital and 1-year mortality rates of ≤13% and ≤15%, respectively. In contrast, patients who received a redo-LT for PNF showed worse outcomes with some values dramatically outside the redo-LT benchmarks. CONCLUSION: This study shows that redo-LT achieves good outcome when looking at benchmark scenarios. However, this figure changes in high-risk redo-LT, as for example in PNF. This analysis objectifies for the first-time results and efforts for redo-LT and can serve as a basis for discussion about the use of scarce resources.

Liver growth prediction in ALPPS - A multicenter analysis from the international ALPPS registry.

BACKGROUND: While ALPPS triggers a fast liver hypertrophy, it is still unclear which factors matter most to achieve accelerated hypertrophy within a short period of time. The aim of the study was to identify patient-intrinsic factors related to the growth of the future liver remnant (FLR). METHODS: This cohort study is composed of data derived from the International ALPPS Registry from November 2011 and October 2018. We analyse the influence of demographic, tumour type and perioperative data on the growth of the FLR. The volume of the FLR was calculated in millilitre and percentage using computed-tomography (CT) scans before and after stage 1, both according to Vauthey formula. RESULTS: A total of 734 patients were included from 99 centres. The median sFLR at stage 1 and stage 2 was 0.23 (IQR, 0.18-0.28) and 0.39 (IQR: 0.31-0.46), respectively. The variables associated with a lower increase from sFLR1 to sFLR2 were age˃68 years (p = .02), height ˃1.76 m (p ˂ .01), weight ˃83 kg (p ˂ .01), BMI˃28 (p ˂ .01), male gender (p ˂ .01), antihypertensive therapy (p ˂ .01), operation time ˃370 minutes (p ˂ .01) and hospital stay˃14 days (p ˂ .01). The time required to reach sufficient volume for stage 2, male gender accounts 40.3% in group ˂7 days, compared with 50% of female, and female present 15.3% in group ˃14 days compared with 20.6% of male. CONCLUSIONS: Height, weight, FLR size and gender could be the variables that most constantly influence both daily growths, the interstage increase and the standardized FLR before the second stage.

Inferior Survival Is Associated With Socioeconomic Deprivation in Hepatocellular Carcinoma.

INTRODUCTION: Pernicious health disparities have been reported in patients with hepatocellular carcinoma (HCC). Few tools exist to screen patients in order to facilitate educational and outreach initiatives. We hypothesize that neighborhood-level socioeconomic metrics such as the Area Deprivation Index (ADI) can predict inferior outcomes in patients with early-stage HCC. METHODS: A single institution's retrospective review of patients with Surveillance, Epidemiology, and End Results Stage I HCC between 2000 and 2020 was conducted. Univariate and multivariate models were constructed to identify clinical and socioeconomic variables correlated with treatment-specific survival. Kaplan-Meier analysis was performed to compare survival differences between cohorts. RESULTS: A total of 558 patients were included in this study with newly diagnosed Surveillance, Epidemiology, and End Results Stage I HCC. Multivariate models demonstrated native model of end-stage liver disease, largest tumor size, insurance type, the distance to our transplant center, and the ADI score, a validated metric for a patient's socioeconomic status, are independent risk factors for worse overall survival (all P-values < 0.05). Concerningly, despite similar maximal tumor size, number of tumors, and native model of end-stage liver disease scores, patients from high ADI neighborhoods are 20% less likely to receive surgical treatment, especially liver transplantation. CONCLUSIONS: The ADI is a useful tool for identifying patients at the time of presentation who are at risk for inferior treatment for early stage HCC, and the ADI should be incorporated as a social vital sign.

What is the optimal prophylaxis against postoperative deep vein thrombosis in the living donor to avoid complications and enhance recovery? - A systematic review of the literature and expert panel recommendations.

BACKGROUND: Deep venous thrombosis (DVT) prophylaxis is often employed to prevent the potentially serious complication of pulmonary embolism (PE). However, little data exist regarding the optimal DVT prophylaxis strategy for living donors undergoing hepatectomy for living donor liver transplantation. Here we present our consensus statement on DVT prophylaxis for living donors undergoing hepatectomy. OBJECTIVES: To identify the optimal DVT prophylaxis strategy, which reduces, risk of complications in living liver donors, and enhances recovery. METHODS: Systematic review following PRISMA guidelines and recommendations using the GRADE approach derived from an international expert panel. Of interest was the impact of DVT prophylaxis or lack of prophylaxis on living donors undergoing hepatectomy and subsequent rates of DVT, PE, and hemorrhagic complications. PROSPERO ID: CRD42021260720 RESULTS: The review of the literature identified three studies, which directly addressed thrombogenesis following living donor hepatectomy. All studies were observational in nature without randomization into treatments. The rate of DVT-PE in unscreened living donors with chemoprophylaxis was 5%. Furthermore, thromboelastography of living donors demonstrated sustained hypercoagulability for 50% of donors 10 days postoperatively. In line with CHEST (The American College of Chest Physicians) guidelines of chemoprophylaxis for surgical procedures with 3% or greater risk of DVT-PE, we conclude that a minimum of 10 days of postoperative chemoprophylaxis with unfractionated heparin or low-molecular weight heparin is recommended for patients undergoing living donor hepatectomy. The quality of evidence (QOE) for these recommendations based on the GRADE criteria is low, with a Grade of Recommendation of Strong. CONCLUSIONS: Chemoprophylaxis for DVT following living donor hepatectomy is associated with reduced adverse thrombotic events, (Quality of Evidence; Low | Grade of Recommendation; Strong).

Evolution and Transformation of Uterine Transplantation: A Systematic Review of Surgical Techniques and Outcomes.

BACKGROUND: Uterine transplantation (UTx) is acknowledged to be on the second (2A) of five steps of development in accordance with the staging system for the evaluation of surgical innovations. Accordingly, we aimed to systematically review the available evidence of the surgical techniques and outcomes of UTx in terms of graft survival. METHODS: A comprehensive search was conducted across PubMed Medline, Cochrane-EBMR, Scopus, Web of Science, and CENTRAL through November 2020. RESULTS: Forty studies, reporting 64 recipients and 64 donors, satisfied inclusion criteria. The surgical time and the estimated blood loss were 515 minutes and 679 mL for graft procurement via laparotomy, 210 minutes and 100 mL for laparoscopic-assisted graft harvest, and 660 minutes and 173 mL for robotic-assisted procedures, respectively. Urinary tract infections (n = 8) and injury to the urinary system (n = 6) were the most common donor complications. Using the donor's internal iliac system, two arterial anastomoses were performed in all cases. Venous outflow was accomplished through the uterine veins (UVs) in 13 cases, a combination of the UVs and the ovarian/uteroovarian veins (OVs/UOVs) in 36 cases, and solely through the OVs/UOVs in 13 cases. Ischemia time was 161 and 258 minutes when using living donors (LD) and deceased donors (DD), respectively. Forty-eight uteri were successfully transplanted or fulfilled the purpose of transplantation, 41 from LDs and 7 from DDs. Twenty-five and four live childbirths from LDs and DDs have been reported, respectively. CONCLUSION: UTx is still experimental. Further series are required to recommend specific surgical techniques that best yield a successful transplant and reduce complications for donors and recipients.

Abdominal Wall Vascularized Composite Allotransplantation: A Scoping Review.

BACKGROUND: Abdominal wall vascularized composite allotransplantation (AW-VCA) is a novel reconstructive technique used for large abdominal wall defects in combination with intestinal transplantation (ITx) or multivisceral abdominal transplantation (MVTx). Since the introduction of this procedure, several studies have been published reporting their experience. This study aims to present a scoping review looking at all available evidence-based medicine information to understand the most current surgical techniques and clinical outcomes. METHODS: This scoping review followed the Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) extension for scoping reviews checklist. A comprehensive research strategy of several databases was conducted. RESULTS: A total of 31 studies were included in this review, which comprised animal, cadaveric, and human studies. In human studies, four surgical techniques with high flap survival rates and low complication rates were found. In cadaveric studies, it was shown that the use of iliofemoral cuff-based flaps provided adequate tissue perfusion to the abdominal wall graft. Also, the use of thoracolumbar nerves have been described to provide functionality to the AW-VCA and prevent long-term muscle atrophy. CONCLUSION: AW-VCA is a safe and efficient alternative for patients with large and complex abdominal wall defects. The future holds a promising evolution of a functional AW-VCA, though surgeons must face and overcome the challenge of distorted anatomy frequently present in this population. Forthcoming studies with a better level of evidence are required to evaluate functionality and differences between surgical techniques.

Early postoperative ERAS compliance predicts decreased length of stay and complications following liver resection.

BACKGROUND: Enhanced recovery after surgery (ERAS) components for liver resection lack standardization and compliance. We evaluated our ERAS protocol and describe the association of postoperative ERAS compliance with length of stay (LOS) and complications. METHODS: We retrospectively reviewed patients undergoing liver resection at our institution from 2016 to 2020. Pre- and post-ERAS outcomes and compliance at 72 h were compared with LOS and complications. LOS beyond 72 h was defined as LOS72. RESULTS: 210 patients were included. Post-ERAS patients had significantly shorter LOS (5.1 vs. 7.3 days, p = 0.0014) with no difference in 30-day mortality, morbidity, or readmissions. ERAS components associated with shorter LOS72 were regular diet (HR 1.73), fluid discontinuation (HR 1.63), drain removal (HR 1.94), multimodal and oral analgesia (HR 1.51), and ambulation >100 ft (HR 2.23). LOS72 was 1-day for ≥9 ERAS component compliance, 4-days for 6-8 components, and 6-days for <6 components. 30-day complication rates for patients with ≥9 components by postoperative day 3 (POD3) were significantly lower than those with 6-8 (12 vs 32%). CONCLUSION: ERAS decreases LOS after liver resection. Nutritional advancement, drain discontinuation, multimodal and oral analgesia, and ambulation >100 ft by POD3 are associated with decreased LOS72. Achieving ≥6 components by POD3 predicts decreased LOS72 and complications.

How to Handle Arterial Conduits in Liver Transplantation? Evidence From the First Multicenter Risk Analysis.

OBJECTIVE: The aims of the present study were to identify independent risk factors for conduit occlusion, compare outcomes of different AC placement sites, and investigate whether postoperative platelet antiaggregation is protective. BACKGROUND: Arterial conduits (AC) in liver transplantation (LT) offer an effective rescue option when regular arterial graft revascularization is not feasible. However, the role of the conduit placement site and postoperative antiaggregation is insufficiently answered in the literature. STUDY DESIGN: This is an international, multicenter cohort study of adult deceased donor LT requiring AC. The study included 14 LT centers and covered the period from January 2007 to December 2016. Primary endpoint was arterial occlusion/patency. Secondary endpoints included intra- and perioperative outcomes and graft and patient survival. RESULTS: The cohort was composed of 565 LT. Infrarenal aortic placement was performed in 77% of ACs whereas supraceliac placement in 20%. Early occlusion (≤30 days) occurred in 8% of cases. Primary patency was equivalent for supraceliac, infrarenal, and iliac conduits. Multivariate analysis identified donor age >40 years, coronary artery bypass, and no aspirin after LT as independent risk factors for early occlusion. Postoperative antiaggregation regimen differed among centers and was given in 49% of cases. Graft survival was significantly superior for patients receiving aggregation inhibitors after LT. CONCLUSION: When AC is required for rescue graft revascularization, the conduit placement site seems to be negligible and should follow the surgeon's preference. In this high-risk group, the study supports the concept of postoperative antiaggregation in LT requiring AC.