Aborted living-donor liver transplantation in the real-world setting, lessons from 13 937 cases of Vanguard Multi-center Study of International Living Donor Liver Transplantation Group.

There are exceedingly uncommon but clearly defined situations where intraoperative abortions are inevitable in living-donor liver transplantation (LDLT). This study aimed to summarize the cases of aborted LDLT and propose a strategy to prevent abortion or minimize donor damage from both recipient and donor sides. We collected data from a total of 43 cases of aborted LDLT out of 13 937 cases from 7 high-volume hospitals in the Vanguard Multi-center Study of the International Living Donor Liver Transplantation Group and reviewed it retrospectively. Of the 43 cases, there were 24 recipient-related abortion cases and 19 donor-related cases. Recipient-related abortions included pulmonary hypertension (n = 8), hemodynamic instability (n = 6), advanced hepatocellular carcinoma (n = 5), bowel necrosis (n = 4), and severe adhesion (n = 1). Donor-related abortions included graft steatosis (n = 7), graft fibrosis (n = 5), primary biliary cholangitis (n = 3), anaphylactic shock (n = 2), and hemodynamic instability (n = 2). Total incidence of aborted LDLT was 0.31%, and there was no remarkable difference between the centers. A strategy to minimize additional donor damage by delaying the donor's laparotomy or trying to open the recipient's abdomen with a small incision should be effective in preventing some causes of aborted LDLT, such as pulmonary hypertension, advanced cancer, and severe adhesions.

TEMPORARY REMOVAL: A novel scoring system to predict short-term mortality after living donor liver transplantation for acute liver failure.

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An international survey of venous thromboembolic events and current practices of peri-operative VTE prophylaxis after living donor hepatectomy.

BACKGROUND: Venous thromboembolic complications are an uncommon but significant cause of morbidity & mortality after live donor hepatectomy . The precise incidence of these events and the current practices of centers performing living donor liver transplantation worldwide are unknown. METHODS: An online survey was shared amongst living donor liver transplantation centers containing questions regarding center activity, center protocols for donor screening, peri-operative thromboembolic prophylaxis and an audit of -perioperative venous thromboembolic events after live donor hepatectomy in the previous five years (2016-2020). RESULTS: Fifty-one centers from twenty countries completed the survey. These centers had cumulatively performed 11500 living donor liver transplants between 2016-2020. All centers included pre-operative l assessment for thromboembolic risk amongst potential liver donors in their protocols. Testing for inherited prothrombotic conditions was performed by 58% of centers. Dual-mode prophylaxis was the most common practice (65%), while eight and four centers used single mode or no routine prophylaxis respectively. Twenty (39%) and 15 (29%) centers reported atleast one perioperative deep venous thrmobosis or pulmonary embolism event respectively. There was one donor mortality directly related to post-operative pulmonary embolism. Overall incidence of deep venous thrombosis and pulmonary embolism events was 3.65 and 1.74 per 1000 live donor hepatectomies respectively. Significant variations in center practices and incidence of thromboembolic events was identified in the survey primarily divided along world regions. 75% of participating centers agreed on the need for clear international guidelines. CONCLUSION: Venous thromboembolic events after live donor hepatectomy are an uncommon but important cause of donor morbidity. There is significant variation in practice among centers. Evidence-based guidelines regarding risk assessment, and peri-operative prophylaxis are needed.

Pediatric combined living donor liver and kidney transplantation for primary hyperoxaluria type 2.

We report the case of a 12-year-old boy with primary hyperoxaluria type 2 (PH2) presenting with end-stage renal disease and systemic oxalosis who underwent a combined living donor liver and kidney transplant from 3 donors, 1 of whom was a heterozygous carrier of the mutation. Plasma oxalate and creatinine levels normalized immediately following the transplant and remain normal after 18 months. We recommend combined liver and kidney transplantation as the preferred therapeutic option for children with primary hyperoxaluria type 2 with early-onset end-stage renal disease.

Viscoelastic Monitoring in Liver Transplantation.

Cirrhosis and liver transplantation (LT) surgery are associated with substantial alterations to the patient's coagulation status. Accurate monitoring of these changes during LT can help manage bleeding proactively and potentially reduce transfusion requirements. Unlike conventional coagulation tests (CCTs), viscoelastic monitoring (VEM) can provide an accurate, real-time, point-of-care assessment of coagulation status during LT and hence has become an invaluable tool for anesthetists and intensive care physicians. However, it remains an enigmatic subject for transplantation surgeons who are more conversant with CCTs. This review discusses the principles of VEM, provides a primer to understanding and interpreting its output, and explains how it can be used to make real-world clinical decisions during LT.

Neurological complications in pediatric liver transplant recipients.

INTRODUCTION: There is paucity of data on neurological complications (NCs) and its predisposing factors, in pediatric liver transplant (PLT) recipients. METHODS: Records of seventy-one children who underwent LT between October 2018 and November 2019 were reviewed. Patients were categorized into group A: with NC and group B: without NC in the post-LT period. Various risk factors contributing to NC were studied. RESULTS: In total, 15 (21.1%) had NC (group A) and 56 (78.9%) had no NC in the post-LT period. NC included cerebrovascular accident (n = 1), seizures (n = 5; 4 generalized, 1 focal), central pontine myelolysis (CPM) (n = 1), diaphragmatic palsy (n = 2), peripheral neuropathy (n = 1), extrapyramidal movements (n = 3), and encephalopathy beyond 96 h (n = 2). The median onset of NC was at 8.5 days post-LT (1-58 days). Ten (66.7%) patients in group A had grades 2-4 hepatic encephalopathy (HE) prior to LT. Eight (14.3%) patients in group B also had pre-LT neurological issues including HE in six, epilepsy and spastic diplegia in one each. On univariate analysis, pre-existing HE, high PELD/MELD score, pre-LT ventilation, pre-LT infection, higher day 1 post-operative bilirubin (all p < .05), and higher tacrolimus were found to predict post-operative NC whereas on multivariate analysis, pre-LT HE was the only predictive factor. Median follow-up was 15.5 months. Four patients died in each group (survival log-rank p = .369). All the surviving patients in group A (n = 11) fully recovered from the NC. CONCLUSION: Pre-transplant HE was the single most significant predisposing factor for post-LT neurological complications.

Newly proposed classification of celiac artery variations based on embryology and correlation with computed tomography angiography.

Purpose: We studied the prevalence of celiac trunk and its anatomical variations on diagnostic computed tomography angiography (CTA) studies and have proposed a new classification to define the celiac artery (CA) variations based on embryology. Material and methods: We retrospectively assessed the celiac trunk variations in 1113 patients who came to our department for diagnostic CTA for liver and renal donor workup. The patient data were acquired from the Picture Archiving and Communication System of our institutions. We analysed the celiac trunk's origin and branching pattern, including the superior mesenteric artery (SMA) and inferior phrenic artery (IPA). Results: We evaluated the CTA studies of 1050 patients. A normal trifurcation pattern, the most common type, was observed in 39% of cases. Variation with CA + left IPA was the most common subtype. Other variations noted in the study and their incidences are listed in the table below. We attempted to propose a new classification based on embryo-logy, which comprises 6 main types and their subtypes. We also analysed previous studies from the literature, including cadaveric, post-mortem, CTA, and digital subtraction angiography studies and compared them with the present study. Conclusions: Because variations of CA classifications reported to date do not encompass all CA branching pattern variants, we have proposed a new classification that incorporates most of the variants. We reiterate the clinical importance of anatomical variants of CA, IPA, and SMA in surgical and interventional radiology procedures.

Propensity Score-Matched Analysis of Posttransplant Outcomes in Living Donor Liver Transplantation for Older Adult Recipients.

The impact of increasing recipient age on morbidity and mortality following living donor liver transplantation (LDLT) remains controversial. The study aims to analyze the impact of recipient age on outcomes following LDLT. Data on adult LDLTs performed between November 2009 and February 2020 were retrieved from a prospectively maintained database. Patients were stratified into 2 groups based on recipient age: 18 to 65 years (younger adults) and >65 years (older adults). Propensity score matching (PSM) using nearest-neighbor matching was used to match each older recipient with up to 2 younger adult recipients using multiple preoperative parameters. Outcomes evaluated were duration of ventilation, need for reintubation, tracheostomy, intensive care unit (ICU) readmission, length of ICU and hospital stays, postoperative complications, reoperation within 90 days, and patient survival. A total of 801 adult LDLT recipients were included in the study; 751 (93.7%) were younger adults, and 50 (6.3%) were older adults. Older recipients were more likely to be diabetic (60.0% versus 39.7%) and hypertensive (44.0% versus 20.4%) with preexisting cardiac disease (28.0% versus 11.2%). However, their pretransplant Model for End-Stage Liver Disease score was significantly lower (14.5 versus 17.7), and they were more likely to receive a transplant because of hepatocellular carcinoma (38.0% versus 17.7%). Older recipients had longer durations of ventilation after LT both before (3.7 versus 1.9 days) and after PSM (4.0 versus 1.5 days). After PSM, the 30-day (13.0% versus 2.4%), 90-day (15.2% and 2.4%), and overall mortality rates (21.7% versus 7.1%) were significantly higher for older recipients when compared with younger recipients. There was no difference between the younger and older recipients with respect to other postoperative outcomes. This propensity score-matched study shows that the older LDLT recipients have higher 30-day, 90-day, 1-year, and 5-year mortality rates when compared with matched younger counterparts.

Non-standard hepatic venous reconstruction in the setting of absent inferior vena cava in partial graft pediatric liver transplantation-A matched retrospective cohort study.

Recipient cava may be unavailable for outflow reconstruction in some children undergoing liver transplantation (PLT) due to caval agenesis, tumor, or fibrotic caval occlusion. Non-standard hepatic venous reconstruction (NHVR) with a direct veno-caval anastomosis or neo-cava reconstruction is necessary in such cases. Retrospective review of all PLT needing NHVR performed in our unit from January 2010 to September 2019 was performed. Outcomes of this group were compared to a 2:1 matched control group who underwent transplantation with standard piggyback technique. Fifteen children (4.9%) of 304 PLT recipients underwent NHVR. Caval agenesis in biliary atresia (n = 5, 33%) and hepatoblastoma infiltrating the cava (n = 4, 27%) were the commonest indications. Ten children had neo-cava reconstruction, while 5 had direct anastomosis to the supra-hepatic caval cuff or right atrium. One child had developed neo-cava thrombosis without graft venous outflow obstruction in the post-operative period. There was no significant difference in major morbidity, need for re-operation (20% vs 16.7%; P = 1.00), hospital stay (24 days, vs 21 days; P = .32), graft & patient survival among the study and control groups. Absent or inadequate recipient cava during PLT with a partial liver graft can be safely managed with technical modifications. Results equivalent to standard piggyback implantation can be achieved.

Delayed Expulsion of biliary cast after hepaticojejunostomy for post-liver transplantation biliary stricture-better cut than canulate?

BACKGROUND: Biliary strictures after living donor liver transplantation (LDLT) are a significant cause of post-transplant morbidity. Endoscopic therapy is usually the first choice of treatment though surgical treatment may provide better biliary drainage. METHODS: We report a case of LDLT performed in a child for acute liver failure who developed an anastomotic biliary stricture with biliary cast formation. We performed a Roux en Y hepaticojejunostomy to treat the stricture. RESULTS: Allograft function improved after surgery with no further episodes of cholangitis. Two months after the surgery, the child passed a large biliary cast in the stools. This reiterates the advantage of wide biliary drainage provided through surgical therapy. CONCLUSIONS: Surgery for biliary strictures following LDLT may provide superior long term biliary drainage- especially when biliary casts are present.

Improved survival in children with HPS: Experience from two high volume liver transplant centers across continents.

BACKGROUND: Severe HPS increases morbidity and mortality after LT in children. We reviewed the combined experience of LT for HPS in children from two LT centers in Europe and Asia. METHODS: All children with "proven" HPS as per ERS Task Force criteria (detailed in manuscript) who underwent LT were categorized into M (PaO2 ≥80 mmHg), Mo (PaO2  = 60-79 mmHg), S (50-59 mmHg), and VS (PaO2 <50 mmHg) HPS, based on room air PaO2 . RESULTS: Twenty-four children with HPS underwent 25 LT (one re-transplantation) at a median age of 8 years (IQR, 5-12), after a median duration of 8 (4-12) months following HPS diagnosis. Mechanical ventilation was required for a median of 3 (1.5-27) days after LT. Ten children had "S" post-operative hypoxemia, requiring iNO for a median of 5 (6-27) days. "VS" category patients had significantly prolonged invasive ventilation (median 35 vs. 3 and 1.5 days; p = .008), ICU stay (median 39 vs. 8 and 8 days; p = .007), and hospital stay (64 vs. 26.5 and 23 days; p < .001) when compared to "S" and "M/Mo" groups, respectively. The need for pre-transplant home oxygen therapy was the only factor predicting need for re-intubation. Patient and graft survival at 32 (17-98) months were 100% and 95.8%. All children ultimately had complete resolution of HPS. CONCLUSIONS: VS HPS is associated with longer duration of mechanical ventilation and hospital stay, which emphasizes the need for early LT in these children.

Right hepatic arterial girdle around the common hepatic duct in liver donors: technical considerations for successful living donor liver transplantation.

PURPOSE: Variations in hepatic arterial anatomy can result in multiple arterial trunks in the graft liver. We describe our experience in dealing with five right lobe liver donors where in the right hepatic artery (RHA) branches were passing anterior and posterior to the common hepatic duct (CHD) forming an arterial girdle around it. METHODS: Five of 771 right lobe living donor liver transplants (January 2012 and March 2020) demonstrated the RHA girdle around the CHD. Three patients had the typical girdle resulting in two graft arteries which were reconstructed using arterial Y grafts. Arterial girdle was formed by the right anterior hepatic artery branches in one patient resulting in 3 graft arteries of which two were reconstructed using a Y graft. One donor had the arterial girdle and an accessory artery from SMA giving rise to 3 graft arteries. Two of them were ligated (brisk back bleed), and one was reconstructed. RESULTS: All donors (median follow-up 17 months, range 6-60 months) had an uneventful postoperative recovery. No vascular or biliary complications were encountered in the recipients. One recipient died due to sepsis and multiorgan failure, while the other 4 recipients recovered uneventfully and continue to have stable graft function. CONCLUSION: Adhering to safe surgical principles during RHA mobilization, ligation of minor arterial branches, and precise reconstruction of multiple major branches can ensure successful outcomes in the donor and recipient in this scenario.

The Role and Therapeutic Potential of NF-kappa-B Pathway in Severe COVID-19 Patients.

Coronavirus disease 2019 (COVID-19) pandemic has affected health care systems worldwide. Severe presentations of COVID-19 such as severe pneumonia and acute respiratory distress syndrome (ARDS) have been associated with the post-viral activation and release of cytokine/chemokines which leads to a "cytokine storm" causing inflammatory response and destruction, mainly affecting the lungs. COVID-19 activation of transcription factor, NF-kappa B (NF-κB) in various cells such as macrophages of lung, liver, kidney, central nervous system, gastrointestinal system and cardiovascular system leads to production of IL-1, IL-2, IL-6, IL-12, TNF-α, LT-α, LT-ß, GM-CSF, and various chemokines. The sensitised NF-κB in elderly and in patients with metabolic syndrome makes this set of population susceptible to COVID-19 and their worse complications, including higher mortality. Immunomodulation at the level of NF-κB activation and inhibitors of NF-κB (IκB) degradation along with TNF-α inhibition will potentially result in a reduction in the cytokine storm and alleviate the severity of COVID-19. Inhibition of NF-κB pathway has a potential therapeutic role in alleviating the severe form of COVID-19.

An international multicenter study of protocols for liver transplantation during a pandemic: A case for quadripartite equipoise.

BACKGROUND & AIMS: The outbreak of COVID-19 has vastly increased the operational burden on healthcare systems worldwide. For patients with end-stage liver failure, liver transplantation is the only option. However, the strain on intensive care facilities caused by the pandemic is a major concern. There is an urgent need for ethical frameworks to balance the need for liver transplantation against the availability of national resources. METHODS: We performed an international multicenter study of transplant centers to understand the evolution of policies for transplant prioritization in response to the pandemic in March 2020. To describe the ethical tension arising in this setting, we propose a novel ethical framework, the quadripartite equipoise (QE) score, that is applicable to liver transplantation in the context of limited national resources. RESULTS: Seventeen large- and medium-sized liver transplant centers from 12 countries across 4 continents participated. Ten centers opted to limit transplant activity in response to the pandemic, favoring a "sickest-first" approach. Conversely, some larger centers opted to continue routine transplant activity in order to balance waiting list mortality. To model these and other ethical tensions, we computed a QE score using 4 factors - recipient outcome, donor/graft safety, waiting list mortality and healthcare resources - for 7 countries. The fluctuation of the QE score over time accurately reflects the dynamic changes in the ethical tensions surrounding transplant activity in a pandemic. CONCLUSIONS: This four-dimensional model of quadripartite equipoise addresses the ethical tensions in the current pandemic. It serves as a universally applicable framework to guide regulation of transplant activity in response to the increasing burden on healthcare systems. LAY SUMMARY: There is an urgent need for ethical frameworks to balance the need for liver transplantation against the availability of national resources during the COVID-19 pandemic. We describe a four-dimensional model of quadripartite equipoise that models these ethical tensions and can guide the regulation of transplant activity in response to the increasing burden on healthcare systems.

Awareness and concerns about novel coronavirus disease 2019 (COVID-19) among parents of pediatric liver transplant recipients.

OBJECTIVES: Pediatric transplant recipients may be at increased risk of developing serious infections due to COVID-19. We undertook a web-based survey among parents of post-liver transplant pediatric patients to assess knowledge and concerns regarding COVID-19 pandemic and impact of social media on them. METHODS: This cross-sectional online survey was conducted between March 21 and March 26, 2020. A 19-item questionnaire was sent to 172 parents of post-liver transplant children. RESULTS: 106 (62%) of parents responded. Median time since transplant was 31 (12-52) months. The majority of parents had good understanding regarding symptomatology and routes of transmission. Only 27% were aware of feco-oral transmission, and 34% knew about gastrointestinal symptoms of COVID-19. 100% of parents understood concept of social distancing, and 70% knew that asymptomatic individuals can transmit the virus. Television followed by newspapers was the main source of their information, though over 40% claim to regularly receive information through social media. 87% would consult their doctor if the child had flu-like symptoms rather than modify immunosuppression or try alternative medications. Parental concerns mainly revolved around early recognition of symptoms, queries on unconventional treatments circulating over social media, and supply of medications during the lockdown period. CONCLUSIONS: The majority of parents had basic understanding of COVID-19 pandemic. Social media appeared to be an important source of information. Results from this survey helped us in modifying patient care protocols to ensure continuity of care while maintaining social distancing.

Uncommon presentation of a recurrent diaphragmatic hernia after pediatric liver transplantation.

DH is a rare but well-recognized complication of PLT. However, a recurrent DH in the setting of PLT has not been reported. We report the case of a child who had previously undergone a DH repair early after PLT and presented more than two years later with atypical findings of severe sepsis and a tender abdominal swelling.

Nationwide Survey on the Knowledge, Attitudes and Perceptions among the Indian Adult Population regarding COVID-19.

BACKGROUND AND OBJECTIVES: Nearly three months after its first recorded case, the progression of the coronavirus disease (COVID-19) pandemic has been slow in India so far, with relatively low number of cases and deaths. The behavior of the general public will probably have the most important bearing on the course of the disease over the next few months in India. We aim to study the awareness, attitudes and perceptions of COVID-19 among the adult Indian population. METHODS: A cross-sectional online survey was conducted using the 'Google Survey Forms' between 29th March and 14th April 2020 and distributed through email and various social media groups. RESULTS: There were 1502 respondents, majority were male (56.7%), between 30-49 years (47.7%). 90% of the respondents had either an undergraduate or postgraduate degree, with a third of them being in the healthcare sector (34.6%). Most of the respondents were aware of the common symptoms of COVID-19, but worryingly only a third (31%) were aware of the risk of spread from infected asymptomatic individuals, which is a major concern in India. Majority were aware of the modes of virus transmission, but only two-thirds (68.6%) were aware of the safe physical distance (6 feet) for maintain social distancing. A majority of respondents were appreciative of the government interventions in containing the virus spread and would support further extension of lockdown if necessary. CONCLUSION: Despite limitations of generalizability, this survey has identified areas which the public health authorities need to target in future information campaigns.

Feasibility and Safety of Split-Liver Transplantation in a Nascent Framework of Deceased Donation.

Split-liver transplantation (SLT) is a valuable option for optimizing the use of good-quality deceased donor grafts. It is not routinely reported outside the West because of limited deceased donor numbers, technical and organizational constraints, lack of experience, and a predominant living donor liver transplantation (LDLT) practice. At our center, 20% of the liver transplantations (LTs) are from deceased donors. We report our experience of SLT and compare outcomes with pediatric and adult LDLT recipients. A prospectively maintained database of all LT recipients between September 2009 and March 2017 was analyzed. Each pediatric SLT recipient was matched to 2 pediatric LDLT recipients for age, weight, urgency, and year of transplant. Each adult SLT recipient was similarly matched to 2 adult LDLT recipients for age, Model for End-Stage Liver Disease score, and year of transplant. Intraoperative and postoperative parameters, including recovery time, morbidity (biliary and vascular complications, Clavien grade >IIIA complications), and mortality were compared. In total, 40 SLTs were performed after splitting 20 deceased donor livers (in situ, n = 11; hybrid split, n = 3; and ex vivo, n = 6). Recipients included 22 children and 18 adults. There were 18 livers that were split conventionally (extended right lobe and left lateral segment [LLS]), and 2 were right lobe-left lobe SLTs. Also, 3 LLS grafts were used as auxiliary grafts for metabolic liver disease. Perioperative mortality in SLT recipients occurred in 3 patients (2 children and 1 adult). Incidence of vascular, biliary, and Clavien grade >IIIA complications were similar between matched adult and pediatric SLT and LDLT groups. In conclusion, SLT is an effective technique with outcomes comparable to living donor grafts for adult and pediatric recipients. Using SLT techniques at centers with limited deceased donors optimizes the use of good-quality whole grafts and reduces the gap between organ demand and availability.

Living donor liver transplantation in Alagille syndrome-Single center experience from south Asia.

To analyze the clinical characteristics and the outcomes of living donor liver transplantation in children with Alagille syndrome (AGS). Clinical data of children with AGS who underwent liver transplantation between July 2009 and May 2019 in our unit were retrospectively analyzed. Primary end-points were patient and graft survival. Ten children with AGS underwent living donor liver transplantation at a median age of 28 months (range, 12-84 months). Jaundice was the most common initial symptom and was noted after a median duration of 20 days after birth (range, 7-60 days). Two patients had undergone Kasai porto-enterostomy for misdiagnosis of biliary atresia. The most common indication for transplantation was severe pruritus with poor quality of life. Explant livers in three children showed cirrhosis with early well-differentiated hepatocellular carcinoma. We have 100% patient and graft survival at a mean follow-up of 32 months (range 3-72 months). The median z-score for weight and height at liver transplantation was -2.66 (range: -6.44 to -0.9) and -3.6 (range: -7.96 to -0.93) while at follow-up was -1.7 (range: -3.4 to -0.35) and -2.1 (range: -3.9 to -1.4), respectively. The estimated glomerular filtration rate was normal pretransplant and follow-up. This is the first series of LDLT for Alagille syndrome in the Indian sub-continent. We report excellent post-transplant outcomes in contrast to outcomes reported from Western literature.

Progression of living liver donation worldwide.

PURPOSE OF REVIEW: Living donor liver transplantation (LDLT) has developed into a well tolerated and viable option when deceased donor transplantation is not available. Transplant and advanced hepatobiliary surgeons from around the world have performed living donor hepatectomies consistently for decades with acceptable donor outcomes. However, optimizing the preoperative workup, donor selection, operative technique, and perioperative care will improve these outcomes. This manuscript reviews recent worldwide literature for the living liver donor. RECENT FINDINGS: Overall, younger living donors produce better recipient outcomes but with careful selection donor over 55 years old may be used safely. Magnetic resonance is becoming the imaging of choice for living donor preoperative planning and its ability to predict steatosis may make predonation liver biopsy unnecessary. Programs with experience in LDLT and laparoscopic liver resection are making significant progress toward consistent use of the laparoscopic approach to living donor hepatectomy. Biliary, pulmonary, and infectious complications are the predictable complications with more serious complications and donor death being very rare. In a majority of cases, the donor's health-related quality of life and psychological well being are preserved. SUMMARY: These recent findings will allow us to better care for the living liver donor and enable LDLT continued progress.