Deceased Donor Liver Transplantation Research Articles

S374 Endoscopic Coiling of Mesenteric Varices Causing Stomal Bleeding Caused by Extensive Portal Vein and Superior Mesenteric Thrombus

Introduction: Ectopic varices are collateral vessels located outside the gastro-esophageal area. Small bowel varices, while an uncommon result of portal hypertension can be a life-threatening cause of gastrointestinal bleeding. We present a case of refractory stomal bleeding secondary to mesenteric varices, treated with endoscopic ultrasound (EUS) guided coiling. Case Description/Methods: A 54-year-old male presented with history of ulcerative colitis status post proctocolectomy and ileostomy, primary sclerosing cholangitis (PSC), and auto-immune hepatitis (AIH) overlap syndrome treated with a deceased donor liver transplant in 2019. This was further complicated by portal hypertension secondary to portal vein and superior mesenteric vein thrombus. The patient presented with refractory stomal bleeding at this ileostomy site requiring multiple blood transfusions. On CT imaging, prominent mesenteric varices extending to the area of the stoma were noted. An interventional radiology (IR) approach from the portal system was not feasible given thrombosis in the portal vein and superior mesenteric vein. Percutaneous IR approach was also felt to be suboptimal given the depth of the peri-stomal varices. After a multidisciplinary discussion, the patient underwent ileoscopy with EUS guided coiling of the terminal/culprit branches of the mesenteric varices. The linear echoendoscope was introduced through the ileostomy and advanced approximately 5-10cm. Multiple tubal anechoic structures consistent with varices were noted with flow seen on doppler examination. This was confirmed on pulse wave doppler. A large feeding variceal vein towards the patient’s left side was punctured with a 22G needle. Saline was injected and it was visualized on EUS to confirm location. Next, embolization coils (8mm x 2, 10mm x1) were inserted for varix eradication. Reduced flow downstream of the coiling site was confirmed on doppler exam after embolization. Brief fluoroscopic images showed appropriate placement of coils in the patients right lower quadrant, without any migration. There was no significant flow toward the lumen on EUS after coiling. Since this procedure, the patient’s stomal bleeding resolved. (Figure) Discussion: Small bowel varices in the setting of significant portal hypertension are a rare but clinically significant cause of gastrointestinal bleeding. EUS-guided interventions such as coil embolization can be an effective treatment modality, especially in patients who are poor interventional radiology candidates. Watch the video at https://tinyurl.com/ACGAbstractS374Figure 1.: (1a) Prominent mesenteric varices extending into the ostomy (1b) EUS-guided coil embolization (1c) Status post successful endoscopic coil embolization

S1229 The Feasibility and Safety of Selected Liver Grafts Flushed With Cold Normal Saline (NS) and Comparison With Liver Grafts Flushed With Histidine-Tryptophan-Ketoglutarate Solution in Living Donor Liver Transplantation

Introduction: Preservation solutions are required for organ viability in deceased donor liver transplantation (LT). However, their role in live donor LT (LDLT) has not been standardized. The aim of this study is to compare the outcomes of selected liver grafts flushed with cold normal saline (NS) with Histidine-Tryptophan-Ketoglutarate (HTK) solution. Methods: One hundred consecutive adult recipients who underwent right lobe LDLT from February 2020 to December 2020 at Gambat, Pakistan were studied. Recipients were assigned to receive “no preservation solution” (cases/non-HTK group; n=50) based on shorter CIT & no back Table reconstruction work or “HTK group” (controls; n=50) requiring standard back Table reconstruction. Various outcomes, including early graft dysfunction (bilirubin, transaminases, and INR), postoperative complications (biliary & vascular), hospital stay, and one-year survival, were compared between the two groups. The direct cost was also reported. Results: Demographics and clinical characters were comparable in the two groups. Comparing cases vs. controls, mean bilirubin, ALT, AST, and INR on the 7thpostoperative day were similar in the two groups. 5(10%) cases and 4(8%) controls developed EAD(p=0.72). Post-LT complications (biliary leak 2% in cases vs. 0 in control), strictures (12% in cases vs. 16% in controls), hepatic artery thrombosis (4% vs. 2%) and portal vein thrombosis (0 vs. 2%) were equally distributed. Mean hospital stay (11.02 + 2.63 and 12.06 + 3.68 days) and 30-day mortality (8% vs 8%) were also comparable in two groups. Finally, 1-year survival (92% vs 90%) based on Kaplan-Meier analysis was also comparable (p-value:0.71). The cost of using a non-HTK-based approach was much lesser than the HTK solution. (Figure) Conclusion: To our knowledge, this is the first innovative report on avoiding preservative solutions in LDLT recipients. We found that EAD including liver function tests; post-operative complications (biliary and vascular), 30 days’ mortality, and 1-year survival were comparable in the two groups. We also found that avoiding the preservative solution has an impact on saving direct costs. (Table). In our study, the postoperative complications and the overall one-year survival rate in the non-preservation group (92%) and the HTK group (90%) were equal and matched with other studies from the region. From an economic perspective, we also found that avoiding the use of preservation solutions is very attractive.Figure 1.: Kaplan-Meier showing a comparable survival rate in non-HTK and HTK groups at 1-year post-liver transplantation Table 1. - Recipient demographics, clinical characteristics, laboratory values, and complications in study groups Recipient demographics, clinical characteristics, laboratory values, and complications in study groups. Variables non-HTK group (n=50) HTK group (n=50) p-value Recipients Age(years) 39.18+11.69 36.84+6.77 0.224 Gender 44(88%) 46 (92%) 0.741 Male 6(12%) 4 (08%) Female BMI(kg/m2) 22.46±4.29 22.84±4.24 0.657 Etiology Viral 47 (94%) 45 (90%) NASH 2 (04%) 1 (02%) Alcoholic 00 (00%) 00 (00%) Budd Chiari 00 (00%) 1 (02%) PBC 00 (00%) 1 (02%) Wilson 1 (02%) 1 (02%) PSC 00 (00%) 1 (02%) HCC 11 (22%) 02 (04%) 0.015 Co-Morbidities DM 4 (08%) 2 (04%) 0.67 HTN 00 (00%) 3 (06%) 0.24 CVD 00 (00%) 00 (00%) 0.00 CTP score 0.59 A 3 (06%) 1 (02%) B 9 (18%) 9 (18%) C 38 (76%) 40 (80%) MELD-Na 19.53±5.51 20.88±4.75 0.19 Operation time (min) 537±70.66 534.60±60.72 0.85 Blood loss(ml) 1622±317.70 1512±300.775 0.07 Hospital stays(days) 11.02±2.63 12.06±3.68 0.10 Mean Post-operative labs (at day 07) Total bilirubin (mg/dL)INR (IU/L)ALT (IU/L)AST (IU/L) 2.96 ± 2.97 3.06 ± 3.24 0.91 1.44 ± 0.24 1.39 ± 0.18 0.82 186.79 ± 144.95 137.69 ± 97.28 0.05 119.69 ± 133.45 93.78 ± 85.65 0.26 Complication EAD 4 (8%) 5(10%) 0.727 PNF 00 1 (2%) 0.315 ACR 3(6%) 4 (8%) 0.695 HAT 2 (4%) 1(2%) 0.558 Sepsis 5 (10%) 4 (8%) 0.727 PVT 00 1 (2%) 0.315 Biliary complicationsStrictureLeak 6 (12%)1 (2%) 8 (16%)00 0.5640.315 Clavin-dindo Grade>III 11 (22%) 13 (26%) 0.64 30-day Mortality 4 (8%) 4 (8%) 1.00 1-year mortality (excluding 1st month) 00 1 (2%) 0.315 BMI: body mass index; HCC: hepatocellular carcinoma; HTN: hypertension; CVD: cardiovascular disease; CTP: Child Turcotte Pugh; INR: international normalized ratio; ALT: alanine aminotransferase; AST: aspartate aminotransferase; EAD: early graft dysfunction; PNF: primary non-function; ACR: acute cellular rejection; HAT: hepatic artery thrombosis; PVT: portal vein thrombosis.

Dengue Transmission From Donor to Recipient After Deceased Donor Liver Transplant; Report of a Case and Review of Literature: Is Liver a Privileged Organ?

Nonvector transmission of dengue virus via organ transplantis rare.We report a probable case of dengue virus transmission via deceased donorlivertransplant. The donor was asymptomatic for dengue infection, and the liver recipient developed fever and thrombocytopenia 8 days after transplant. The recipient's testresults were positive forthe antigen for nonstructural protein 1 and for immunoglobulin M; however, donor serum samples were not available. Other transplant recipients (renal allograft) also showed dengue-positive test results during the same period, and these patients eventually died. Dengue illness in the liver recipient was severe and associated with shock and cardiomyopathy that required mechanical ventilation, intensive care, and cessation of immunosuppression; however, the patient subsequently improved and was discharged. This case highlights the importance of a high index of suspicion for dengue infection in the presence of graft dysfunction in dengue-endemic areas like India, as well as the importance of the test for the nonstructural protein 1 antigen during dengue outbreaks. These considerations should be included on the standard evaluation of solid-organ transplant donors.

S2995 Gallstone Ileus: An Unusual Cause of Small Bowel Obstruction After Liver Transplantation

Introduction: Liver transplantation is the only curative treatment for patients with decompensated liver disease. The prevalence of biliary complications after a deceased donor liver transplant is estimated between 10 to 15%. Biliary leaks and strictures are the most common biliary complications. We are presenting a rare case of gallstone ileus at the biliary limb in a patient with a complicated post-liver transplant course. Case Description/Methods: A 78-year-old female with a history of NASH cirrhosis for which she underwent a deceased donor liver transplant ten years before presentation. Post-transplant course was complicated by anastomotic biliary strictures, recurrent choledocholithiasis, and recurrent cholangitis requiring multiple ERCPs with placement of multiple biliary stents. She underwent Roux-en-Y hepaticojejunostomy three years before presentation with marked improvement in the number of cholangitis episodes. She presented with intractable nausea and vomiting. Physical exam showed abdominal distention and periumbilical tenderness but no rebound tenderness or rigidity. Labs were significant for a mild rise in serum creatinine but no leukocytosis and liver chemistries were normal. CT abdomen revealed small bowel obstruction with a transition point at the right lower quadrant anastomosis suspecting phytobezoar at the jejuno-jejunal anastomosis. The patient underwent push enteroscopy to decompress the obstructed limb and remove the suspected food material. The scope was advanced to the jejuno-jejunal anastomosis. About 15 cm beyond the afferent limb, the lumen was entirely occluded by a giant stone measuring (3.5 cm x 2.5 cm). The stone had sequential rings and appeared as a cholesterol stone. The stone was fragmented using grasping forceps, snares, and dilating balloons. It was successfully fragmented into 15-20 smaller stones over three hours duration. The scope was advanced beyond the fragmented stones. A nasogastric tube was inserted for decompression. Patient symptoms resolved following the procedure, and she was discharged home with no recurrence. (Figure) Discussion: Biliary leaks and strictures are the most common biliary complications following liver transplant. Gallstone ileus should be considered in liver transplant patients presenting with small bowel obstruction, especially if they have a history of recurrent biliary complications. Prompt recognition of this complication is key, endoscopic lithotripsy should be attempted first in these patients as they are usually high risk surgical candidates.Figure 1.: Panel A: CT abdomen and pelvis showing dense luminal material at the transition point. Panel B: Endoscopic image of the cholesterol stone occluding the lumen before lithotripsy. Panel C: Endoscopic image of the cholesterol stone after the lithotripsy.

S1221 Changes in Disease Etiology of Deceased Donor Liver Transplantations Following Acuity Circles Policy Implementation

S1221 Changes in Disease Etiology of Deceased Donor Liver Transplantations Following Acuity Circles Policy Implementation

S2956 Delayed Onset Drug-Induced Acute Liver Failure Caused by Glatiramer Acetate (GA) in Multiple Sclerosis Requiring Liver Transplantation

Introduction: Glatiramer acetate (GA) has been used for multiple sclerosis (MS) since 1996. Regular liver function test monitoring is not required for the medication because there have not been any reported cases of liver toxicity.1Here, we report the first case of delayed onset GA-induced ALF requiring liver transplantation. Case Description/Methods: A 59-year-old woman with well-controlled MS presented to the emergency department with three weeks of jaundice and dark-colored urine. Initial labs showed AST 2527 IU/L (81x ULN), ALT 2512 IU/L (81x ULN), total bilirubin 22.7 mg/dL (19x ULN), ALP 210 IU/L (2x ULN), INR 2.65. Further workup showed normal ceruloplasmin, alpha-1-antitrypsin, and IgG. Hepatitis, HSV, VZV, T-spot, HIV, ANA, anti-mitochondrial antibody, anti-LKM antibody were negative. Anti-smooth muscle antibody was 1:40. Her liver enzymes were normal one year prior to presentation, and she had no family history of autoimmune or liver disease. Computed tomography abdomen/pelvis showed patent vasculature and no evidence of cirrhosis. MRI/MRCP showed no biliary obstruction. Her only medication was GA, which she had been taking since 2008. Physical exam was notable for mild asterixis, and she was started on IV N-acetyl cysteine for 3 days. Liver biopsy demonstrated submassive necrosis (70%) consistent with drug induced liver injury (Fig. 1A). GA was thought to be the most likely etiology of her liver injury and was held. Liver transplant was ultimately deferred because her liver enzymes and her mental status improved. She was discharge on day 6. Four days later she developed severe abdominal pain, lethargy and re-presented to the hospital. She was slow to respond, had scleral icterus and asterixis with AST 909 IU/L, ALT 839 IU/L, total bilirubin 27.2 mg/dL, INR 2.94. The patient underwent expedited liver transplant evaluation and was listed on the same day. She successfully underwent deceased donor liver transplant three days later. Liver explant showed mixed zone 1 and 3 liver necrosis (50%) with associated inflammation, mild lobular inflammation and cholestasis (Fig. 1B-D). Discussion: Our case illustrates the first case of GA-induced ALF requiring liver transplantation. Previous reports showed that patients with GA drug-induced-liver injury recovered completely in 1-5 months after drug withdrawal and time of presentation ranges from 1 to 8 months, as opposed to 14 years in our case. Patients on GA should have long term regular liver monitoring.Figure 1.: Histological analysis of pre-transplant and explant liver. A. Hematoxylin and eosin (H&E) stain of the pre-transplant biopsy showed extensive necrosis including zone 3 (x100). B. Gross picture of explant (weight 500.3 gram). The surface showed wrinkles, which were characteristics of acute liver failure with massive hepatocyte necrosis. C. H&E stain of explant showed no viable hepatocytes in the worst area. (x200). D. Masson trichrome stain showed no fibrosis, which confirms the acute process (x200).

Clinical analysis of deceased donor liver transplantation in the treatment of hepatocellular carcinoma with segmental portal vein tumor thrombus: A long-term real-world study.

BackgroundHepatocellular carcinoma (HCC) patients with portal vein tumor thrombus (PVTT) have conventionally been regarded as a contraindication for liver transplantation (LT). However, the outcomes of deceased donor liver transplantation (DDLT) in patients with segmental PVTT remain unknown. The aim of this study is to evaluate the feasibility and effectiveness of DDLT in the treatment of HCC with segmental PVTT.MethodsWe retrospectively analyzed 254 patients who underwent DDLT for HCC in our institution from January 2015 to November 2019. To assess the risks of PVTT, various clinicopathological variables were evaluated. Overall (OS) and recurrence-free survival (RFS) analyses based on different PVTT types were performed in HCC patients.ResultsOf the 254 patients, a total of 46 patients had PVTT, of whom 35 had lobar PVTT and 11 had segmental PVTT in second-order branches or below. Alpha-fetoprotein (AFP) level, tumor maximal diameter, histological grade, micro-vascular invasion (MVI), RFS, and OS were significantly different between the control and PVTT groups. Lobar PVTT was associated with unfavorable 5-year RFS and OS compared with MVI group (28.6% and 17.1%, respectively). Instead, no significant difference was observed between the segmental PVTT and MVI group in terms of 5-year RFS and OS (RFS: 36.4% vs. 40.4%, p=0.667; OS: 54.5% vs. 45.1%, p=0.395). Further subgroup analysis showed segmental PVTT with AFP levels ≤100 ng/ml presented significantly favorable RFS and OS rates than those with AFP level >100 ng/ml (p=0.050 and 0.035, respectively).ConclusionsIn summary, lobar PVTT remains a contraindication to DDLT. HCC patients with segmental PVTT and AFP level ≤100 ng/ml may be acceptable candidates for DDLT.

Liver transplantation during COVID-19: Adaptive measures with future significance.

Following the outbreak of coronavirus disease 2019 (COVID-19), a disease caused by the novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the field of liver transplantation, along with many other aspects of healthcare, underwent drastic changes. Despite an initial increase in waitlist mortality and a decrease in both living and deceased donor liver transplantation rates, through the implementation of a series of new measures, the transplant community was able to recover by the summer of 2020. Changes in waitlist prioritization, the gradual implementation of telehealth, and immunosuppressive regimen alterations amidst concerns regarding more severe disease in immunocompromised patients, were among the changes implemented in an attempt by the transplant community to adapt to the pandemic. More recently, with the advent of the Pfizer BNT162b2 vaccine, a powerful new preventative tool against infection, the pandemic is slowly beginning to subside. The pandemic has certainly brought transplant centers around the world to their limits. Despite the unspeakable tragedy, COVID-19 constitutes a valuable lesson for health systems to be more prepared for potential future health crises and for life-saving transplantation not to fall behind.

Treprostinil Supplementation Ameliorates Hepatic Ischemia Reperfusion Injury and Regulates Expression of Hepatic Drug Transporters: An Isolated Perfused Rat Liver (IPRL) Study

PurposeIR injury is an unavoidable consequence in deceased donor liver transplantation. Cold preservation and warm reperfusion may change the expression and function of drug transporters in the liver due to vasoconstriction, infiltration of neutrophils and release of cytokines. We hypothesize that vasodilation, anti-platelet aggregation and proinflammatory downregulation activities of treprostinil will diminish the IR injury and its associated effects.MethodsLivers obtained from male SD rats (n = 20) were divided into 1) Control, 2) IR, 3) Treprostinil-1 (preservation only), and 4) Treprostinil-2 (preservation and reperfusion) groups. Control livers were procured and immediately reperfused. Livers in the other groups underwent preservation for 24 h and were reperfused. All the livers were perfused using an Isolated Perfused Rat Liver (IPRL) system. Periodic perfusate, cumulative bile samples and liver tissue at the end of perfusion were collected. Liver injury markers, bile flow rates, m-RNA levels for uptake and efflux transporters (qRT-PCR) were measured.ResultsCold preservation and warm reperfusion significantly increased the release of AST and ALT in untreated livers. Treprostinil supplementation substantially reduced liver injury. Bile flow rate was significantly improved in treprostinil-2 group. m-RNA levels of Slc10a1, Slc22a1, and Slc22a7 in liver were increased and m-RNA levels of Mdr1a were decreased by IR. Treprostinil treatment increased Abcb11 and Abcg2 m-RNA levels and maintained Slc22a1m-RNA similar to control livers.ConclusionsTreprostinil treatment significantly reduced liver injury. IR injury changed expression of both uptake and efflux transporters in rat livers. Treprostinil significantly altered the IR injury mediated changes in m-RNA expression of transporters.

Impact of sustained viral response for hepatitis C virus on the outcomes of liver transplantation in hemophilic patients with human immunodeficiency virus/hepatitis C virus co-infection: A nationwide survey in Japan.

Human immunodeficiency virus (HIV)/hepatitis C virus (HCV) co-infection from blood products for hemophilia has been a social problem in Japan, and liver transplantation (LT) for these patients has been a challenging procedure. However, with the advent of the direct-acting antiviral agent for HCV and change in the policy for prioritization of deceased donor LT, the results of LT for patients co-infected with HCV/HIV may have improved. This study was conducted to provide updated results of our nationwide survey of LT for patients co-infected with HCV/HIV, from January 1997 to December 2019. We collected data on 17 patients with HIV/HCV co-infection who underwent either deceased donor LT (n=5) or living donor LT (n=12). All the patients were men with hemophilia, and the median age was 41 (range, 23-61) years. The median CD4 count before LT was 258 (range, 63-751). Most patients had poor liver function before surgery with Child-Pugh grade C and a Model for End-stage Liver Disease score of 20 (range, 11-48). The right lobe was used for most grafts for living donor liver transplantation (n=10). Overall survival was significantly better with a sustained viral response (SVR) than without an SVR, and a univariate analysis indicated that SVR after direct-acting antiviral or interferon/ribavirin showed the highest hazard ratio for patient survival after LT. A multivariate analysis was not possible because of the limited number of cases. SVR for HCV showed the highest impact on the outcome of LT for patients with hemophilia co-infected with HIV/HCV. SVR for HCV should be achieved before or after LT for patients with hemophilia co-infected with HIV/HCV for a better outcome.

344.1: C-Reactive Protein and Urea Levels Distinguish Primary Non-function From Early Allograft Dysfunction After Liver Transplantation

Introduction: A spectrum of graft dysfunction occurs after liver transplantation (LT), ranging from early allograft dysfunction (EAD) to primary non-function (PNF). There are no single or uniformly accepted laboratory parameters that differentiate these entities. Several biochemical markers are exclusively made in the liver, including urea, C-reactive protein (CRP) and fibrinogen. However, these are given les prominence than transaminases, bilirubin and International Normalised Ratio (INR). The aim of this study was to determine if routinely measured serum biochemical markers can distinguish PNFfrom EAD in the initial 48 hours following deceased donor liver transplantation. Methods: A retrospective study of all adult patients that underwent LTat our institution between January 2010 and April 2020 was performed. Patients that experienced graft loss from a complication other than PNF in the initial 14 days were excluded. Patients were grouped into an immediate graft function (IGF), EAD, and a PNF groups. The absolute values and trends of CRP, blood urea, serum transaminases, INR and fibrinogen in the initial post-operative 48 hours were compared between groups. Biochemical factors found to be significantly different between groups on univariable analysis were further investigated using receiver operating characteristic (ROC) curves. The area under the receiver operating characteristic curve (AUROC) value was reported, and the Youden index was used to identify the optimum cut-off values. Results: During the study period, 2102 LTs were performed and 1937 were eligible for inclusion. There were 1394 patients with IGF (72%), 503 with EAD (26%) and 40 with PNF (2%) patients according to the study definition. A significantly greater proportion of grafts were from donors following cardiac death (DCD) in the PNF group compared to the EAD group (45% vs. 29%; p=0.04). The median (IQR) of each variable and the accuracy in distinguishing PNF from EAD is demonstrated in table 1 and 2 respectively. Lack of an increment in CRP (Day 2:1; 1.43 v 1.77, P=0.01) and urea production between on day 1 and 2 (Day 2:1; 0.71 vs 1.32, P=<0.01). The CRP level was significantly lower in the group that experienced PNF on both day 1 and 2 (Day 1; 20 v 43, P=<0.01, Day 2: 24 v 47, p=<0.01,). Urea production was significantly lower on post-operative day 2 in the PNF group (Day 2; 5.1 v 9.0, p=<0.01). An aspartate transaminase (AST) threshold of 2409 IU/L on post operative day 2 had the highest accuracy in distinguishing PNF from EAD (AUC; 0.83, Sensitivity: 81.3%, Specificity 81.4%). Discussion: CRP and AST are more effective than ALT and bilirubin in distinguishing PNF from EAD in the initial post operative 48 hours. Clinicians should consider the values of these markers when making treatment decisions for patients with early liver allograft dysfunction.

211.8: Impact of Sarcopenia Using Anterior Thigh Skeletal Muscle Index on Clinical Outcomes in the Liver Transplant Recipient

Backgrounds: Sarcopenia is defined as loss of skeletal muscle strength, mass, and function. It has been reported as a significant risk factor for outcomes after Liver transplantation (LT) as well as waitlist mortality in end-stage liver disease patients. Although there are various imaging modalities and measurement methods for diagnosing sarcopenia, the gold standard is not clear. The purpose of this study is to analyze the effect of sarcopenia on outcome in LT patients using previously known third lumbar (L3)-skeletal muscle index (SMI) cut-off values and newly calculated anterior thigh (AT)-SMI cut-off values. Method: Three hundred forty-one patients who underwent living and deceased donor liver transplantation in our center from Jan 2018 to Dec 2020 were analyzed. L3-SMI and AT-SMI were obtained by measuring preoperative computed tomography scans with semiautomatic software. For L3-SMI, the cut-off values reported in other previous studies were applied (42 cm2/m2 in males, 38 cm2/m2 in females). For AT-SMI, the optimal cut-off value was obtained by the ROC curve for sarcopenia. Results: The prevalence of sarcopenia diagnosed by L3-SMI was 29.9 % (102/ 341) and by AT-SMI was 35.5 % (121/ 341) in our cohort. The cut-off values of AT-SMI obtained by ROC curve were 12.6 cm2/m2 for female (AUC = 0.915, P < 0.001) and 14.2 cm2/m2 for male (AUC = 0.882, P < 0.001). Patient and graft survival rates in the sarcopenia group by AT-SMI were significantly lower than in the non-sarcopenia group (P < 0.001, P < 0.001). AT-SMI was identified as one of the independent prognostic factors in patient survival in multivariable cox analysis, whereas L3-SMI was not (HR, 4.462; 95 % CI, 1.792 – 11.106; P = 0.001). It was also confirmed by ROC curve analysis that AT-SMI was more highly correlated than L3-SMI for patient survival (P = 0.005). Conclusion: Both the L3-SMI and AT-SMI-induced sarcopenia group had a significantly lower patient and graft survival than the group without sarcopenia. However, AT-SMI was identified as an independent prognostic factor for patient survival and was more correlated with patient survival than L3-SMI. This means that AT-SMI may be a better option than L3-SMI for the evaluation of CT-based sarcopenia in LT recipients.

P9.31: Devising Bile Duct Anastomosis to Reduce Biliary Complications in Living Donor Liver Transplantation at Our Hospital

Background: Living donor liver transplantation has become an important treatment for end-stage liver disease. In living donor liver transplantation, the biliary tract is thinner and shorter than in deceased donor liver transplantation. For this reason, it has been reported that biliary complications are more frequent in living donor liver transplantation. We have been devising bile duct anastomosis to reduce bile leak and biliary stricture. In this study, we examined the results of our efforts and report the changes in the surgical technique and perioperative management at our hospital. Methods: 210 patients who underwent living donor liver transplantation at our hospital by November 2021 were included in this study. Conventionally, biliary tract reconstruction was performed under direct vision with a circumferential interrupted suture and placement of an internal short stent. From March 2013 to May 2016, microsurgical outer knotted suture was used to reconstruct the biliary tract without sutured knots in the lumen. After a period of regression to the conventional method, since May 2019, biliary tract reconstruction has been performed with continuous sutures on the posterior wall and interrupted sutures on the anterior wall and external drainage as the basic stenting technique. 28 patients since May 2019 and 182 patients before May 2019 were divided into two groups. The incidence of bile leak and biliary stricture was examined. Risk factors for bile leak and biliary stricture were also examined in univariate and multivariate analysis. Results: Among all patients, bile leak was observed in 29 cases and biliary stricture in 38 cases. In the current method group, there were 6 cases of bile leak and 4 cases of biliary stricture, with no significant difference between the two groups. Risk factors for bile leak were the number of reconstructed bile ducts and operative time in the univariate analysis. In multivariate analysis, only operative time was identified as an independent risk factor. Risk factors for biliary stricture were bile leak and operative time in the univariate analysis. In multivariate analysis, bile leak was identified as an independent risk factor for biliary stricture. Neither the current method of reconstruction nor the previous method were identified as risk factors. Conclusion: In the present study, biliary tract reconstruction with continuous sutures on the posterior wall and interrupted sutures on the anterior wall and external drainage, which is currently performed at our hospital, showed no significant difference from conventional methods in both bile leak and biliary stricture. Because of the small number of cases, further study is needed in the future.

Normothermic liver machine perfusion as a dynamic platform for regenerative purposes: What does the future have in store for us?

Liver transplantation has become an immense success; nevertheless, far more recipients are registered on waiting lists than there are available donor livers for transplantation. High-risk, extended criteria donor livers are increasingly used to reduce the discrepancy between organ demand and supply. Especially for high-risk livers, dynamic preservation using machine perfusion can decrease post-transplantation complications and may increase donor liver utilisation by improving graft quality and enabling viability testing before transplantation. To further increase the availability of donor livers suitable for transplantation, new strategies are required that make it possible to use organs that are initially too damaged to be transplanted. With the current progress in experimental liver transplantation research, (long-term) normothermic machine perfusion may be used in the future as a dynamic platform for regenerative medicine approaches, enabling repair and regeneration of injured donor livers. Currently explored therapeutics such as defatting cocktails, RNA interference, senolytics, and stem cell therapy may assist in the repair and/or regeneration of injured livers before transplantation. This review will provide a forecast of the future utility of normothermic machine perfusion in decreasing the imbalance between donor liver demand and supply by enabling the repair and regeneration of damaged donor livers.

333.2: Vascular Complications in Pediatric Liver Transplants And Their Management

Introduction: Unlike other organs, the blood supply of the liver occurs through two systems. One of these is the hepatic artery, and it supply approximately one-third to one-fifth of the liver. The rest of the liver is supplied with blood via the portal vein. The outflow of blood circulation in the liver is via the hepatic veins. Any disruption in this blood circulation results in deterioration in liver functions. In this study, we aimed to evaluate early vascular complications in pediatric liver transplants. Methods: From 8 November 1988 to 31 December 2021, we performed 701 LT procedures and 334 of them were pediatric.). We reviewed the medical records of these recipients for the following: primary cause of liver failure, age, and weight at the time of transplantation, type of graft, vascular complications and their management. One hundred and seventy six of the recipients were male and 158 were female. Mean age of 7.34 years (0.5 months – 17 years). Nineteen (5.7%) of the LT were deceased donor LT and 315 (94.3%) were living related liver transplant. Most cause of liver failure was biliary atresia (n=169). Mean weight of recipients was 23.3 kg. Most of graft types was left lateral graft (n=204) Results: Hepatic vein complications occurred in 3 patients. In all three patients, stenosis was detected in the portal vein anastomosis region and was successfully treated with interventional radiological methods by placing a stent in the anastomosis region. Portal vein complications occurred in 3 patients. In one of these patients, hemostasis was performed by surgical method due to bleeding from the portal vein anastomosis. In the second patient, the anastomosis was surgically revised due to thrombus formation in the portal vein. In the third patient, due to a stenosis of more than 50% in the portal vein anastomosis, a stent was placed in the anastomosis region after balloon dilation using interventional radiological methods, and blood flow was successfully maintained. Hepatic artery complications occurred in 54 patients. Hepatic artery thrombosis occurred in 31 patients, hepatic artery stenosis in 13 patients, bleeding from hepatic artery anastomosis in 7 patients, hepatic artery dissection in 2 patients, and pseudoaneurysm in the hepatic artery in 1 patient. 43 of these patients were successfully treated with interventional radiological methods and 11 of them surgically. Conclusion: Vascular complications seen in liver transplants can cause deterioration in hepatic functions and acute liver failure. Especially hepatic artery complications are one of the most important causes of biliary tract complications that will develop in the future. Vascular complications can be successfully treated at an early stage in experienced organ transplant centers.

P9.37: Liver Transplantation for Abernathy Malformation (Congenital Absence of Portal Vein): A Case Report

Introduction: Congenital absence of portal vein (CAPV) is very rare congenital anomaly caused by dysplasia in the portal vein (PV) system leading to diversion of blood from gut directly to IVC without passing liver. Clinically after being asymptomatic it can present with encephalopathy from hyperammonemia and hypoglycemia. Case report: A 8-year old female child who was diagnosed with CAPV was referred to our centre for further evaluation. She was a full-term baby and doing well till 4years of age when she had near fainting. During evaluation she had elevated liver function test, splenomegaly and imaging revealed CAPV with shunting. Her family reported decline in her academic performance over past few years. On index visit her total bilirubin was 1.4 mg/dL, AST 40 IU/L, ALT 29 IU/L and serum ammonia 122 ug/dL with no evidence of hepatopulmonary syndrome. The CECT abdomen revealed common trunk of splenic vein and SMV, directly draining into IVC with prominent hepatic artery (Figure 1). She received deceased donor liver transplant from brain dead donor (Figure 2) and postoperative course was uneventful. Liver function has remained stable with patent PV and hepatic artery. Histology of the native liver showed absent PV with nodular liver parenchyma without cirrhosis. Discussion: CAPV can lead to encephalopathy and mental retardation; hence careful observation of their symptoms, hepatic function, and metabolic abnormalities is required. LT might be indicated for symptomatic CAPV or prophylactic LT is indicated before the development of pulmonary hypertension or HPS.

335.6: Long-term Outcomes of Living Donor Versus Deceased Donor Liver Transplantation for Acute Liver Failure in United States

Introduction: Acute Liver Failure (ALF) is rarely encountered but often is associated with high morbidity and mortality. Timely Liver Transplantation is universally the only accepted rescue therapy, but not much is known about the usage of Living Donor (LDLT) versus Deceased Donor (DDLT)Liver Transplantation in the United States for this indication. Method: United Network of Organ Sharing/ Organ Procurement and Transplantation Network (UNOS/OPTN) data was reviewed from January 2002 to December 2020. Adult and pediatric recipients with diagnostic codes for ALF and listed as Status 1 were included in the study. Clinical, laboratory, and demographic characteristics were compared between LDLT and DDLT groups. In addition, Post-transplant survival rates were compared between the two groups. Results: There were a total of 246 LDLT (3.8%) and 6153 DDLT (96.2%) recipients with the diagnosis of ALF (Table 1). There was a difference in age and gender between the groups, with 93.5% of LDLT cases being for pediatric ALF cases versus 45.9% of DDLT cases being for pediatric recipients of age less than 18. There were more female gender in the DDLT group. Race was not different between the two groups. The proportion of patients waiting ≥ 3 days was 64.1% in DDLT compared to 77.2% in the LDLT group (P<0.001). There was no statistical difference between the two groups in terms of sodium, bilirubin, and INR. There were more patients with hepatic encephalopathy, and on renal replacement therapy in the DDLT group compared to LDLT group. Overall, 1, 5 and 10 year overall survival among the DDLT and LDLT groups were also similar, 87.7% vs. 85.5%, 81.1% vs. 81.1%, 74.7% vs. 79.3% (p=0.16) (Figure 1) (Log rank P=0.16). Conclusions: In the US, LDLT constitutes of only 3.8% of all liver transplants for ALF. In addition, LDLT was mostly used among pediatric recipients (93.5%), whereas DDLT was mostly used for adult recipients (54.1%). Signs of decompensation with hepatic encephlopathy, ascites, and on renal replacement therapy were more common in DDLT than LDLT group. LDLT can be carefully considered in a select group of adult ALF cases, in early phases, before further progression into renal failure and advanced encephalopathy.

Impact of Older Donor Age on Recipient and Graft Survival After LDLT: The US Experience.

The impact of selecting older donors for living donor liver transplantation (LDLT) in the United States is incompletely studied, particularly in light of the recent expansion of LDLT nationally. Adult LDLTs from January 01, 2005 to December 31, 2019 were identified using the United Network for Organ Sharing database. Multivariable Cox models evaluated living donor (LD) age as a predictor of LDLT recipient and graft survival. The impact of increasing donor age on recipient outcomes was compared between LD and deceased donor recipients. Donor postoperative outcomes were evaluated. There were 3539 LDLTs at 65 transplant centers during the study period. Despite the recent expansion of LDLT, the proportion of LDs aged ≥50 y was stable. There were no clinically significant differences in recipient or donor characteristics by LD age group. LD age ≥50 y was associated with an adjusted hazard ratio of 1.49 ( P = 0.012) for recipient survival and 1.61 ( P < 0.001) for graft survival (vs LDs aged 18-29 y). The negative impact of increasing donor age on graft survival was more profound after LDLT than deceased donor liver transplantation (interaction P = 0.019). There was a possible increased rate of early donor biliary complications for donors >55 y (7.1% versus 3.1% for age <40 y; P = 0.156). Increasing LD age is associated with decreased recipient and graft survival, although older donors still largely yield acceptable outcomes. Donor outcomes were not clearly impacted by increasing age, though this warrants further study.

Techniques of hepatic arterial reconstruction in liver transplantation.

Hepatic artery reconstruction is an essential part of liver transplantation. This difficult stage of the operation is even more demanding in living donor liver transplantation than in deceased donor liver transplantation. One of the most important advances in hepatic artery reconstruction for living liver grafts was the introduction of microsurgical techniques involving an operative microscope or surgical loupe. Many surgical reconstruction techniques have been used in this field. In this article, first, we will talk about the hepatic artery reconstruction techniques that are frequently used in deceased donor liver transplantation, and afterward, we will talk about the hepatic artery reconstruction techniques used in living donor liver transplantation, which include the hepatic artery reconstruction technique we use and call "one stay corner suture technique". We think high-volume transplant centers should tend to develop a standardized technique for doing hepatic artery reconstruction with their teams. We think the "one stay corner suture technique" can be easily applied in centers that perform LDLT.

Artificial intelligence for predicting survival following deceased donor liver transplantation: Retrospective multi-center study

BackgroundPrevious studies have indicated that the model for end-stage liver disease (MELD) score may fail to predict post-transplantation patient survival. Similarly, other scores (donor MELD score, balance of risk score) that have been developed to predict transplant outcomes have not gained widespread use. These scores are typically derived using linear statistical models. This study aimed to compare the performance of traditional statistical models with machine learning approaches for predicting survival following liver transplantation. Materials and methodsData were obtained from 785 deceased donor liver transplant recipients enrolled in the Korean Organ Transplant Registry (2014–2019). Five machine learning methods (random forest, artificial neural networks, decision tree, naïve Bayes, and support vector machine) and four traditional statistical models (Cox regression, MELD score, donor MELD score and balance of risk score) were compared to predict survival. ResultsAmong the machine learning methods, the random forest yielded the highest area under the receiver operating characteristic curve (AUC-ROC) values (1-month = 0.80; 3-month = 0.85; and 12-month = 0.81) for predicting survival. The AUC-ROC values of the Cox regression analysis were 0.75, 0.86, and 0.77 for 1-month, 3-month, and 12-month post-transplant survival, respectively. However, the AUC-ROC values of the MELD, donor MELD, and balance of risk scores were all below 0.70. Based on the variable importance of the random forest analysis in this study, the major predictors associated with survival were cold ischemia time, donor ICU stay, recipient weight, recipient BMI, recipient age, recipient INR, and recipient albumin level. As with the Cox regression analysis, donor ICU stay, donor bilirubin level, BAR score, and recipient albumin levels were also important factors associated with post-transplant survival in the RF model. The coefficients of these variables were also statistically significant in the Cox model (p < 0.05). The SHAP ranges for selected predictors for the 12-month survival were (−0.02,0.10) for recipient albumin, (−0.05,0.07) for donor bilirubin and (−0.02,0.25) for recipient height. Surprisingly, although not statistically significant in the Cox model, recipient weight, recipient BMI, recipient age, or recipient INR were important factors in our random forest model for predicting post-transplantation survival. ConclusionMachine learning algorithms such as the random forest were superior to conventional Cox regression and previously reported survival scores for predicting 1-month, 3-month, and 12-month survival following liver transplantation. Therefore, artificial intelligence may have significant potential in aiding clinical decision-making during liver transplantation, including matching donors and recipients.