Adult-to-adult living donor liver transplantation using extended right lobe grafts

The long-term follow-up of the living liver donors

Living donor liver transplantation (LDLT) has been proposed in many countries to reduce organ shortage. While the early postoperative outcomes have been well investigated, little is known about the long-term follow-up of the living donors. We, therefore, designed a systematic review of the literature to explore long-term complications and quality of life among living donors. We searched MEDLINE and EMBASE registries for studies published since 2013 that specifically addressed long-term follow-up following living-donor liver donation, concerning both physical and psychological aspects. Publications with a follow-up shorter than 1 year or that did not clearly state the timing of outcomes were excluded. A total of 2505 papers were initially identified. After a thorough selection, 17 articles were identified as meeting the eligibility criteria. The selected articles were mostly from North America and Eastern countries. Follow-up periods ranged from 1 to 11.5 years. The most common complications were incision site discomfort (13.2-38.8%) and psychiatric disorders (1-22%). Biliary strictures occurred in 1-14% of cases. Minimally invasive donor hepatectomy could improve quality of life, but long-term data are limited. About 30 years after the first reported LDLT, little has been published about the long-term follow-up of the living donors. Different factors may contribute to this gap, including the fact that, as healthy individuals, living donors are frequently lost during mid-term follow-up. Although the reported studies seem to confirm long-term donor safety, further research is needed to address the real-life long-term impact of this procedure.

Indications and results of right-lobe living donor liver transplantation

The shortage of deceased liver donor organs over the years has always posed the need to expand the donor pool. A viable alternative to deceased donors is that of the living donor. Indeed, the living donor in liver transplantation, initially in pediatric transplantation, but for several years now also in adult transplantation, is a more than viable alternative to deceased liver donation. In fact, right liver lobe donation has proven to be a surgical procedure with low impact on the donor's life in terms of morbidity and mortality, with excellent results in recipients of such organs. In recent years, an increasing number of studies have been published that show excellent results in right-lobe living donor liver transplantation, encouraging this practice not only in countries that have historically had a shortage of deceased donor organs, such as Asian countries, but making it a practice of increasing use in Western countries as well. In addition, thanks to improvements in surgical technique and the experience of high-volume centers, this surgery has also begun to be performed using minimally invasive surgical techniques, allowing us to envision ever better outcomes for both donor and recipient in the coming years.

Asian Pacific Association for the Study of the Liver clinical practice guidelines on liver transplantation

Liver transplantation is a highly complex and challenging field of clinical practice. Although it was originally developed in western countries, it has been further advanced in Asian countries through the use of living donor liver transplantation. This method of transplantation is the only available option in many countries in the Asia-Pacific region due to the lack of deceased organ donation. As a result of this clinical situation, there is a growing need for guidelines that are specific to the Asia-Pacific region. These guidelines provide comprehensive recommendations for evidence-based management throughout the entire process of liver transplantation, covering both deceased and living donor liver transplantation. In addition, the development of these guidelines has been a collaborative effort between medical professionals from various countries in the region. This has allowed for the inclusion of diverse perspectives and experiences, leading to a more comprehensive and effective set of guidelines.

Manual and semi-automated computed tomography volumetry significantly overestimates the right liver lobe graft weight: a single-center study with adult living liver donors

PURPOSE

Preoperative evaluation of donor liver volume is indispensable in living donor liver transplantation to ensure sufficient residual liver and graft-to-recipient weight ratio. This study aims to evaluate the accuracy of two computed tomography (CT) volumetry programs, an interactive manual and a semi-automated one, in the preoperative estimation of the right lobe graft weight.

METHODS

One hundred and nine right liver lobe living donors between January 2008 and January 2020 were enrolled in this retrospective study. Two radiologists measured the liver graft volumes independently using manual and semi-automated CT volumetry, and the interaction time was recorded. Actual graft weight (AGW) measured intraoperatively served as the reference standard. The paired samples t-test was used to compare the estimated graft weight (EGW) and the AGW. Inter-user and inter-method agreements were assessed with Bland-Altman plots.

RESULTS

Both manual and semi-automated CT volumetry significantly overestimated the graft weight (EGW manual: 893 ± 155 mL vs. AGW manual: 787 ± 128 g, P < 0.001, EGW semi-automated: 879 ± 143 mL vs. AGW semi-automated, P < 0.001). The junior radiologist measured higher volumes than the senior radiologist with either method (P < 0.001). The Bland-Altman analysis revealed mean difference and standard deviation for inter-method agreement of 7 ± 48 cc for the senior radiologist, and 34 ± 54 cc for the junior radiologist. The mean difference and standard deviation for inter-method agreement was 63 ± 59 cc in manual volumetry and 22 ± 38 cc in semi-automated volumetry. The mean interaction time was 27.3 ± 14.2 min for manual volumetry and 6.8 ± 1.4 min for semi-automated volumetry (P < 0.001).

CONCLUSION

Both manual and semi-automated CT volumetry significantly overestimated the right liver graft weight, while semi-automated volumetry significantly reduced the interaction time.

Liver volumetric and anatomic assessment in living donor liver transplantation: The role of modern imaging and artificial intelligence

The shortage of deceased donor organs has prompted the development of alternative liver grafts for transplantation. Living-donor liver transplantation (LDLT) has emerged as a viable option, expanding the donor pool and enabling timely transplantation with favorable graft function and improved long-term outcomes. An accurate evaluation of the donor liver's volumetry (LV) and anatomical study is crucial to ensure adequate future liver remnant, graft volume and precise liver resection. Thus, ensuring donor safety and an appropriate graft-to-recipient weight ratio. Manual LV (MLV) using computed tomography has traditionally been considered the gold standard for assessing liver volume. However, the method has been limited by cost, subjectivity, and variability. Automated LV techniques employing advanced segmentation algorithms offer improved reproducibility, reduced variability, and enhanced efficiency compared to manual measurements. However, the accuracy of automated LV requires further investigation. The study provides a comprehensive review of traditional and emerging LV methods, including semi-automated image processing, automated LV techniques, and machine learning-based approaches. Additionally, the study discusses the respective strengths and weaknesses of each of the aforementioned techniques. The use of artificial intelligence (AI) technologies, including machine learning and deep learning, is expected to become a routine part of surgical planning in the near future. The implementation of AI is expected to enable faster and more accurate image study interpretations, improve workflow efficiency, and enhance the safety, speed, and cost-effectiveness of the procedures. Accurate preoperative assessment of the liver plays a crucial role in ensuring safe donor selection and improved outcomes in LDLT. MLV has inherent limitations that have led to the adoption of semi-automated and automated software solutions. Moreover, AI has tremendous potential for LV and segmentation; however, its widespread use is hindered by cost and availability. Therefore, the integration of multiple specialties is necessary to embrace technology and explore its possibilities, ranging from patient counseling to intraoperative decision-making through automation and AI.

Current Status of Living Donor Liver Transplantation: Impact, Advantages, and Challenges

PURPOSE OF THIS REVIEW

This review provides an overview of the current status of Living Donor Liver Transplant (LDLT). It discusses the impact of LDLT on waitlist and post-transplantation outcomes, highlighting the technical challenges and unique advantages of LDLT.

RECENT FINDINGS

Recent findings show that LDLT offers several theoretical advantages over deceased donor liver transplant, including shorter wait times, better graft quality, and improved post-transplant outcomes. Non-alcoholic fatty liver disease (NAFLD) and hepatocellular carcinoma (HCC) are emerging as the leading indications for adult LDLT in the US. LDLT demonstrates comparable or better overall survival rates and organ-specific outcomes compared to deceased donor transplants. However, challenges exist, including donor and recipient risks such as biliary complications and small-for-size syndrome. Ongoing research focuses on refining surgical techniques, exploring minimally invasive approaches, utilizing predetermined donors to modulate the recipient's immune system, and ensuring ethical practices. LDLT is a valuable solution for patients with end-stage liver failure or disorders requiring transplantation. It offers advantages such as shorter wait times as well as improved waitlist and post-transplant outcomes. Continued research and advancements in LDLT will benefit patients in need of liver transplantation.

Biomechanics in liver regeneration after partial hepatectomy

The liver is a complicated organ within the body that performs wide-ranging and vital functions and also has a unique regenerative capacity after hepatic tissue injury and cell loss. Liver regeneration from acute injury is always beneficial and has been extensively studied. Experimental models including partial hepatectomy (PHx) reveal that extracellular and intracellular signaling pathways can help the liver recover to its equivalent size and weight prior to an injury. In this process, mechanical cues possess immediate and drastic changes in liver regeneration after PHx and also serve as main triggering factors and significant driving forces. This review summarized the biomechanics progress in liver regeneration after PHx, mainly focusing on PHx-based hemodynamics changes in liver regeneration and the decoupling of mechanical forces in hepatic sinusoids including shear stress, mechanical stretch, blood pressure, and tissue stiffness. Also discussed were the potential mechanosensors, mechanotransductive pathways, and mechanocrine responses under varied mechanical loading in vitro. Further elucidating these mechanical concepts in liver regeneration helps establish a comprehensive understanding of the biochemical factors and mechanical cues in this process. Proper adjustment of mechanical loading within the liver might preserve and restore liver functions in clinical settings, serving as an effective therapy for liver injury and diseases.

Minimally Invasive Donors Right Hepatectomy versus Open Donors Right Hepatectomy: A Meta-Analysis

BACKGROUND

How to obtain a donor liver remains an open issue, especially in the choice of minimally invasive donors right hepatectomy versus open donors right hepatectomy (MIDRH versus ODRH). We conducted a meta-analysis to clarify this question.

METHODS

A meta-analysis was performed in PubMed, Web of Science, EMBASE, Cochrane Central Register, and ClinicalTrials.gov databases. Baseline characteristics and perioperative outcomes were analyzed.

RESULTS

A total of 24 retrospective studies were identified. For MIDRH vs. ODRH, the operative time was longer in the MIDRH group (mean difference [MD] = 30.77 min; p = 0.006). MIDRH resulted in significantly less intraoperative blood loss (MD = -57.86 mL; p < 0.00001), shorter length of stay (MD = -1.22 days; p < 0.00001), lower pulmonary (OR = 0.55; p = 0.002) and wound complications (OR = 0.45; p = 0.0007), lower overall complications (OR = 0.79; p = 0.02), and less self-infused morphine consumption (MD = -0.06 days; 95% CI, -1.16 to -0.05; p = 0.03). In the subgroup analysis, similar results were observed in pure laparoscopic donor right hepatectomy (PLDRH) and the propensity score matching group. In addition, there were no significant differences in post-operation liver injury, bile duct complications, Clavien-Dindo ≥ 3 III, readmission, reoperation, and postoperative transfusion between the MIDRH and ODRH groups.

DISCUSSION

We concluded that MIDRH is a safe and feasible alternative to ODRH for living donators, especially in the PLDRH group.

Outcomes of the Initial Phase of an Adult Living vs Deceased Donor Liver Transplantation Program in a Low-Volume Transplant Center: Integration of Hepatobiliary and Transplant Surgery

BACKGROUND

The development of living donor liver transplantation (LDLT) is clinically challenging, especially in a low-volume transplant program. We evaluated the short-term outcomes of LDLT and deceased donor liver transplantation (DDLT) to demonstrate the feasibility of performing LDLT in a low-volume transplant and/or high-volume complex hepatobiliary surgery program during the initial phase.

MATERIAL AND METHODS

We conducted a retrospective study of LDLT and DDLT in Chiang Mai University Hospital from October 2014 to April 2020. Postoperative complications and 1-year survival were compared between the 2 groups.

RESULTS

Forty patients who underwent LT in our hospital were analyzed. There were 20 LDLT patients and 20 DDLT patients. The operative time and hospital stay were significantly longer in the LDLT group than in the DDLT group. The incidence of complications in both groups was comparable, except for biliary complications, which were higher in the LDLT group. Bile leakage, found in 3 patients (15%), is the most common complication in a donor. The 1-year survival rates of both groups were also comparable.

CONCLUSION

Even during the initial phase of the low-volume transplant program, LDLT and DDLT had comparable perioperative outcomes. Surgical expertise in complex hepatobiliary surgery is necessary to facilitate effective LDLT, potentially increasing case volumes and promoting program sustainability.

In silico modeling for the hepatic circulation and transport: From the liver organ to lobules

The function of the liver depends critically on its blood supply. Numerous in silico models have been developed to study various aspects of the hepatic circulation, including not only the macro-hemodynamics at the organ level, but also the microcirculation at the lobular level. In addition, computational models of blood flow and bile flow have been used to study the transport, metabolism, and clearance of drugs in pharmacokinetic studies. These in silico models aim to provide insights into the liver organ function under both healthy and diseased states, and to assist quantitative analysis for surgical planning and postsurgery treatment. The purpose of this review is to provide an update on state-of-the-art in silico models of the hepatic circulation and transport processes. We introduce the numerical methods and the physiological background of these models. We also discuss multiscale frameworks that have been proposed for the liver, and their linkage with the large context of systems biology, systems pharmacology, and the Physiome project. This article is categorized under: Metabolic Diseases > Computational Models Metabolic Diseases > Biomedical Engineering Cardiovascular Diseases > Computational Models.

Four Decades of Clinical Liver Transplantation Research: Results of a Comprehensive Bibliometric Analysis

BACKGROUND

Nearly 40 y have passed since the 1983 National Institutes of Health Consensus-Development-Conference, which has turned liver transplantation (LT) from a clinical experiment into a routine therapeutic modality. Since' clinical LT has changed substantially. We aimed to comprehensively analyze the publication trends in the most-cited top-notch literature in LT science over a 4-decade period.

METHODS

A total of 106 523 items were identified between January 1981 and May 2021 from the Web of Science Core Collection. The top 100 articles published were selected using 2 distinct citation-based strategies to minimize bias. Various bibliometric tools were used for data synthesis and visualization.

RESULTS

The citation count for the final dataset of the top 100 articles ranged from 251 to 4721. Most articles were published by US authors (n = 61). The most prolific institution was the University of Pittsburgh (n = 15). The highest number of articles was published in Annals of Surgery, Hepatology, and Transplantation ; however, Hepatology publications resulted in the highest cumulative citation of 9668. Only 10% of the articles were classified as evidence level 1. Over 90% of first/last authors were male. Our data depict the evolution of research focus over 40 y. In part, a disproportional flow of citations was observed toward already well-cited articles. This might also project a slowed canonical progress, which was described in other fields of science.

CONCLUSIONS

This study highlights key trends based on a large dataset of the most-cited articles over a 4-decade period. The present analysis not only provides an important cross-sectional and forward-looking guidance to clinicians, funding bodies, and researchers but also draws attention to important socio-academic or demographic aspects in LT.

Expanding the living liver donor pool in countries having limited deceased donor activity: Pakistani perspective

Over the last decades, liver transplantation (LT) has evolved into a life-saving procedure. Due to limited deceased donor activities in the eastern world, living donor liver transplantation (LDLT) had flourished tremendously in most Asian countries. Yet, these LDLT activities fall short of meeting the expected demands. Pakistan, a developing country, bears a major burden of liver diseases. Currently, only few centers offer LDLT services in the country. On the other hand, deceased donor liver transplantation (DDLT) activities have not started due to social, cultural, and religious beliefs. Various strategies can be adopted successfully to overcome the scarcity of live liver donors (LLDs) and to expand the donor pool, keeping in view donor safety and recipient outcome. These include consideration of LLDs with underlying clinical conditions like G6PD deficiency and Hepatitis B core positivity. Extended donor criteria can also be utilized and relaxation can be made in various donors' parameters including upper age and body mass index after approval from the multidisciplinary board. Also, left lobe grafts, grafts with various anatomical variations, and a low graft-to-recipient ratio can be considered in appropriate situations. ABO-incompatible LT and donor swapping at times may help in expanding the LLDs pool. Similarly, legislation is needed to allow live non-blood-related donors for organ donations. Finally, community education and awareness through various social media flat forms are needed to promote deceased organ donation.

OPEN TO ROBOTIC RIGHT DONOR HEPATECTOMY: A TECTONIC SHIFT IN SURGICAL TECHNIQUE

Robotic right live donor hepatectomy(r-LDRH) has been reported with reduced morbidity compared to open donor right hepatectomy(o-LDRH) in few recent series. Nevertheless, its routine use is debated. We present a large series comparing pure r-LDRH with o-LDRH. Consecutive r-LDRH performed from June 2018 to June 2020 (n = 102) were compared with consecutive donors undergoing o-LDRH (n = 152) from February 2016 to February 2018, a period when r-LDRH was not available at this centre. Propensity score matched (PSM) analysis of 89 case-control pairs was additionally performed. Primary endpoints were length of high dependency unit (HDU) & hospital stay and Clavien-Dindo graded complications among donors. Although r-LDRH took longer to perform (540 versus 462 mins, P<0.001), the post-operative peak transaminases levels(P<0.001), the length of HDU (3 versus 4 days, P<0.001) and hospital stay (8 versus 9 days, P<0.001) were lower in in donors undergoing r-LDRH. Clavien-Dindo graded complications were similar (16.67% in r-LDRH and 13.16% in o-LDRH). The rates of early allograft dysfunction (1.6% versus 3.3%), bile leak (14.7% versus 10.7%), and 1-year mortality (13.7% versus 11.8%) were comparable between r-LDRH and o-LDRH recipients. PSM analysis yielded similar results between the groups. These data support the safety and feasibility of r-LDRH in select donors. This article is protected by copyright. All rights reserved.

Liver transplantation in China: Achievements over the past 30 years and prospects for the future

Over the last three decades, liver transplantation (LT) in China has made breakthroughs from scratch. Now, new techniques are being continuously incorporated. However, LT in China differs from that in other countries due to cultural differences and the disease burden. The advances made in and the current issues with LT in China need to be summarized. Living donor LT (LDLT) has developed dramatically in China over the last 30 years, with the goal of increasing transplant opportunities and dealing with the shortage of donors. Western candidate selection criteria clearly are not appropriate for Chinese patients. Thus, the current authors reviewed the literature, and this review has focused on the topics of technological advancements in LDLT and Chinese candidate selection. The Milan criteria in wide use emphasize tumor morphology rather than pathology or biomarkers. α-fetoprotein (AFP) and pathology were incorporated as predictors for the first time in the Hangzhou criteria. Moreover, Xu et al. divided the Hangzhou criteria into type A (tumor size ≤ 8 cm or tumor size > 8 cm but AFP ≤ 100 ng/mL) and type B (tumor size > 8 cm but AFP between 100 and 400 ng/mL), with type B serving as a relative contraindication in the event of a liver donor shortage. In addition, surgeons in Chengdu and Shanghai have the ability to perform a laparoscopic hepatectomy for right and left lobe donors, respectively. China has established a complete LT system, including recipient criteria suitable for Chinese people, a fair donor allocation center, a transplant quality monitoring platform, and mature deceased donor or living donor LT techniques.

The impact of mini-invasive right hepatectomy in the setting of living donation: a meta-analysis

Adult-to-adult living-donor liver transplantation (A2ALDLT) represents a challenging procedure, mainly when the right hepatic lobe is donated. Therefore, especially in Western countries, the medical community still considers it a “risky procedure”. The present meta-analysis investigated the postoperative results reported in donors undergoing right hepatectomy for A2ALDLT through a minimally invasive liver resection (MILR) vs. open liver resection (OLR) approach, with the intent to clarify the hypothesis that the MILR approach should minimize the risks for the donor. A systematic literature search was performed using MEDLINE-PubMed, Cochrane Library, and EMBASE electronic databases. The primary outcome investigated was the complication rate after transplant. Fifteen studies were included (n = 2094; MILR = 553 vs. OLR = 1541). The MILR group only merged the statistical relevance in terms of advantage in terms of a lower number of complications (OR = 0.771, 95% CI 0.578–1.028; P value = 0.077). Investigating the complications ≥ IIIa according to the Dindo-Clavien classification, the estimated blood loss, and the length of hospital stay, no statistical difference was reported between the two groups. MILR represents a novel and promising approach for improving the results in A2ALDLT. However, no benefits have been reported regarding blood loss, length of stay, and postoperative complications. More extensive experiences are needed to re-evaluate the impact of MILR in right lobe live donation.

Strategy for Selective Middle Hepatic Vein Reconstruction in Living Donor Liver Transplantation Using Right Lobe Graft: A Retrospective Observational Study

BACKGROUND

The aim of this study was to verify the safety and feasibility of our selection criteria for middle hepatic vein (MHV) reconstruction in living donor liver transplantation (LDLT) using right lobe grafts.

METHODS

A total of 153 LDLTs were performed using right lobe grafts in a tertiary hospital from 2006 to 2016. Among them, 52 cases without MHV reconstruction were compared with 101 recipients who underwent LDLT using right lobe graft with MHV reconstruction. Both groups were compared regarding indications for reconstruction, short-term and long-term complications, operative details, and outcomes.

RESULTS

The two groups differed only in cold ischemic time (108.19 ± 49.81 minutes vs 146.37 ± 58.74 minutes) preoperatively. Short-term posttransplant outcomes, long-term overall survival, and long-term disease-free survival showed no significant differences between the 2 groups. After propensity score matching for both groups with and without MHV reconstruction to eliminate selection bias, the 2 groups were comparable.

CONCLUSIONS

We found that our selection criteria for performing MHV reconstruction in LDLT using right lobe graft were feasible and safe. A routine MHV reconstruction is not necessary if the right lobe graft graft-to-recipient weight ratio is ≥1.0, right hepatic vein draining territory volume is ≥0.8, and recipient Model for End-Stage Liver Disease score is <20.

Uric Acid as a Predictor for Early Allograft Dysfunction after Living Donor Liver Transplantation: A Prospective Observational Study

Early allograft dysfunction (EAD) is a postoperative complication that may cause graft failure and mortality after liver transplantation. The objective of this study was to examine whether the preoperative serum uric acid (SUA) level may predict EAD. We performed a prospective observational study, including 61 donor/recipient pairs who underwent living donor liver transplantation (LDLT). In the univariate and multivariate analysis, SUA ≤4.4 mg/dL was related to a five-fold (odds ratio (OR): 5.16, 95% confidence interval (CI): 1.41–18.83; OR: 5.39, 95% CI: 1.29–22.49, respectively) increased risk for EAD. A lower preoperative SUA was related to a higher incidence of and risk for EAD. Our study provides a new predictor for evaluating EAD and may exert a protective effect against EAD development.

Cytomegalovirus Latency Exacerbated small-for-size Liver Graft Injury through Activation of CCL19/CCR7 in Hepatic Stellate Cells

BACKGROUND

The interplay between cytomegalovirus (CMV) latency and graft malfunction after living donor liver transplantation (LDLT) remains poorly defined due to the complexity of clinical confounding factors. Here, we aimed to investigate the effects of CMV latency on small-for-size graft injury and to get further insight on the pathogenic role of hepatic stellate cells (HSCs) in this process.

METHODS

Rat orthotopic liver transplantation with small-for-size grafts was performed in a CMV latent model developed in immunocompetent Sprague Dawley (SD) rats using Priscott strain. Post-transplant graft injury including hepatocyte damage, stellate cell activation and fibrogenesis were evaluated. Differential gene expression of HSCs in response to CMV latency was screened by cDNA microarray. Clinical validation was further conducted in human biopsies.

RESULTS

CMV latency aggravated hepatocyte apoptosis/necrosis in the early phase, enhanced HSC expansion and graft fibrosis during the middle-late phase in small-for-size liver grafts of the rat model. cDNA microarray mining revealed CCL19/CCR7 as one of the most noteworthy pathways bridging HSC activation and liver graft injury in the presence of CMV latency. Together with CCL19 upregulation, coherent overexpression of CCR7 in accumulated HSCs was confirmed in both rat and human CMV latent recipients. Moreover, addition of CCL19 in vitro promoted HSC migration by increasing the level of matrix metalloproteinase-2 (MMP2).

CONCLUSION

Our data demonstrated that CMV latency aggravated early/late phase liver graft damage and fibrogenesis via CCL19/CCR7/HSCs axis. Blockade of CMV latency-related stellate cell activation may shed light on the strategy of graft protection clinically.

Safety and feasibility of laparoscopic living donor right hepatectomy for adult liver transplantation: a meta-analysis

BACKGROUND

Laparoscopic living donor right hepatectomy (LDRH) was a controversial topic due to its unknown safety and feasibility.

METHODS

PubMed, EMBASE and Cochrane Library databases were searched for studies comparing LDRH with open living donor right hepatectomy (ODRH), which were published between the date of database establishment and June 2020. Revman5.3 was used for statistical analysis.

RESULTS

Fourteen studies were included. For the donors, there was no significant difference in warm ischemic time, hospital stay, graft weight, hepatic arterial anomalies (HAA), hepatic vein anomalies (HVA), portal vein anomalies (PVA), biliary anomalies, bleeding, wound infection, severe complication rate and readmission rate. The estimated blood loss, incidence of complication, intra-abdominal fluid rate in the LDRH group were significantly lower than those in the ODRH group, while the operation time, time to remove liver in the LDRH group were significantly higher than those in the ODRH group. For the recipients, there was no significant difference in complication rate, bleeding, HAA, PVA, biliary anomalies, graft failure and mortality. The HVA rate in the LDRH group was significantly higher than that in the ODRH group.

CONCLUSION

LDRH is safe and feasible for adult living donor liver transplantation compared with ODRH and it can reduce intraoperative bleeding and postoperative complication in donors, which requires further verification by more multi-center comparative studies with large sample and high quality.

CT and MR imaging evaluation of living liver donors

Preoperative cross-sectional imaging evaluation of potential living liver donors allows to exclude donors with an increased risk for morbidity and mortality, and to assure that a suitable graft for the recipient can be obtained, minimizing the risk of complications in both the donor and the recipient. CT is routinely performed to delineate the anatomy of the liver, relevant vasculature, and liver volumes in whole right or left lateral segment donation. MR imaging is the gold standard for the assessment of biliary anatomy and allows a better quantification of hepatic steatosis compared to CT. Knowledge of normal and variant vascular and biliary anatomy and their surgical relevance for liver transplantation is of paramount importance for the radiologist. The purpose of this review is to outline the current role of CT and MR imaging in the assessment of hepatic parenchyma, hepatic vascular anatomy, biliary anatomy, and hepatic volumetry in the potential living liver donor with short notes on acquisition protocols and the relevant reportable findings.

A nomogram for prediction of early allograft dysfunction in living donor liver transplantation

Liver transplantation is the treatment of choice for end-stage liver diseases. However, early allograft dysfunction (EAD) is frequently encountered and associated with graft loss or mortality after transplantation. This study aimed to establish a predictive model of EAD after living donor liver transplantation. A total of 77 liver transplants were recruited to the study. Multivariate analysis was utilized to identify significant risk factors for EAD. A nomogram was constructed according to the contributions of the risk factors. The predictive values were determined by discrimination and calibration methods. A cohort of 30 patients was recruited to validate this predictive model. Four independent risk factors, including donor age, intraoperative blood loss, preoperative alanine aminotransferase (ALT), and reperfusion total bilirubin, were identified and used to build the nomogram. The c-statistics of the primary cohort and the validation group were 0.846 and 0.767, respectively. The calibration curves for the probability of EAD presented an acceptable agreement between the prediction by the nomogram and the actual incidence. In conclusion, the study developed a new nomogram for predicting the risk of EAD following living donor liver transplantation. This model may help clinicians to determine individual risk of EAD following living donor liver transplantation.

Association of Graft-to-Recipient Weight Ratio with the Prognosis Following Liver Transplantation: a Meta-analysis

BACKGROUND

Studies indicate that low graft-to-recipient weight ratio (GRWR) affect graft survival in adult-to-adult living donor liver transplantation. However, the potential role of GRWR in the prognosis of patients following living donor liver transplantation according to patient characteristics remains controversial. This study aimed to update the role of GRWR in patients following living donor liver transplantation.

METHODS

PubMed, Embase, and Cochrane Library were comprehensively searched for studies comparing low GRWR (< 0.8%) with normal GRWR (≥ 0.8%) in the prognosis following living donor liver transplantation from inception to March 2019. The 1-, 3-, and 5-year summary survival rates, small-for-size syndrome (SFSS), perioperative mortality, biliary complications, postoperative bleeding, and acute rejection were calculated using the random-effects model.

RESULTS

Eighteen studies comprising 4001 patients were included. Patients with low GRWR were associated with lower 1-year and 3-year survival rates compared to patients with normal GRWR, while no significant difference was found in the association of 5-year survival rate with low and normal GRWRs. Moreover, the risk of SFSS significantly increased in patients with low GRWR. Finally, no significant differences were observed in the association of low and normal GRWRs with the risk of perioperative mortality, biliary complications, postoperative bleeding, and acute rejection.

CONCLUSION

The results of this study indicated that low GRWR was associated with poor prognosis for patients following living donor liver transplantation, especially in terms of 1- and 3-year survival rates and SFSS.

Hepatic vein in living donor liver transplantation

Right lobe living donor liver transplantation (LDLT) is a major development in adult LDLT that has significantly increased the donor pool by providing larger graft size and by decreasing risk of small-for-size graft syndrome. However, right lobe anatomy is complex, not only from the inflow but also from the outflow perspective. Outflow reconstruction is one of the key requirements of a successful LDLT and venous drainage of the liver graft is just as important as hepatic inflow for the integrity of graft function. Outflow complications may cause acute graft failure which is not always easy to diagnose. The right lobe graft consists of two sections and three hepatic venous routes for drainage that require reconstruction. In order to obtain a congestion free graft, several types of vascular conduits and postoperative interventions are needed to assure an adequate venous allograft drainage. This review described the anatomy, functional basis and the evolution of outflow reconstruction in right lobe LDLT.

Living donor liver transplantation in small-for-size setting

Small-for-Size Syndrome (SFSS) is one of the most feared complication of adult split liver and living donor liver transplantation. SFSS stems from a disproportionate/excessive portal vein flow relative to the volume of the implanted liver graft, and is currently one of the major practical limits to partial liver grafts' transplantation. In the last few decades many graft inflow modulation (GIM) techniques have been proposed to curtail the portal vein flow, allowing for successful transplantation of small partial liver grafts. Graft inflow modulation techniques span from Splenic Artery Ligation (SAL), to Splenectomy, Porto-Systemic Shunts and the lately proposed Splenic Devascularization. A patient tailored approach balancing the risk of SFSS with GIM specific morbidity, is more important than identifying the ideal GIM technique. Here we summarize the most recently published data to provide general indications in the challenging preoperative choice of a GIM techniques.

Impact of Extra-anatomical Hepatic Artery Reconstruction During Living Donor Liver Transplantation on Biliary Complications and Graft and Patient Survival

BACKGROUND

This study was designed to analyze the feasibility of extra-anatomical hepatic artery (HA) reconstruction in living donor liver transplantation (LT).

METHODS

Patients who underwent their first living donor LT at our center between January 2008 and December 2017 were reviewed. HA reconstruction was classified as anatomical or extra-anatomical reconstruction (EAR). We compared the background characteristics and posttransplantation outcomes, including complications, biliary complications, graft survival, and overall survival. The potential risk factors for bile leakage were analyzed using multivariable logistic regression, while risk factors for biliary stricture-free survival, graft survival, and overall survival were analyzed using multivariable Cox regression.

RESULTS

Among 800 patients, 35 (4.4%) underwent EAR, of whom 7 (7/35, 20.0%) experienced HA complications after the initial anatomical reconstruction and required EAR during reoperation. Patients who underwent EAR (n = 2/35, 5.7%) had a similar rate of HA complications compared with those who underwent anatomical reconstruction (n = 46/772, 5.9%, P = 0.699). EAR was a significant risk factor for bile leakage (odds ratio [OR], 4.167; 95% confidence interval [CI], 1.928-9.006; P < 0.001) along with multiple bile ducts (OR, 1.606; 95% CI, 1.022-2.526; P = 0.040) and hepaticojejunostomy (OR, 4.108; 95% CI, 2.190-7.707; P < 0.001). However, EAR had no statistical relationship to biliary stricture-free survival (hazard ratio [HR], 1.602; 95% CI, 0.982-2.613; P = 0.059), graft survival (HR, 1.745; 95% CI, 0.741-4.109; P = 0.203), or overall survival (HR, 1.405; 95% CI, 0.786-2.513; P = 0.251). HA complications were associated with poor biliary stricture-free survival (HR, 2.060; 95% CI, 1.329-3.193; P = 0.001), graft survival (HR, 5.549; 95% CI, 2.883-10.681; P < 0.001), and overall survival (HR, 1.958; 95% CI, 1.195-3.206; P = 0.008).

CONCLUSION

Extra-anatomical HA reconstruction during living donor LT was not a risk factor for biliary stricture, graft failure, or overall survival.

Minimally Invasive Donor Hepatectomy for Adult Living Donor Liver Transplantation: An International, Multi-Institutional Evaluation of Safety, Efficacy and Early Outcomes

OBJECTIVE

Evaluating the perioperative outcomes of minimally invasive (MIV) donor hepatectomy for adult live donor liver transplants in a large multi-institutional series from both Eastern and Western centers.

BACKGROUND

Laparoscopic liver resection has become standard practice for minor resections in selected patients in whom it provides reduced postoperative morbidity and faster rehabilitation. Laparoscopic approaches in living donor hepatectomy for transplantation, however, remain controversial because of safety concerns. Following the recommendation of the Jury of the Morioka consensus conference to address this, a retrospective study was designed to assess the early postoperative outcomes after laparoscopic donor hepatectomy. The collective experience of 10 mature transplant teams from Eastern and Western countries was reviewed.

METHODS

All centers provided data from prospectively maintained databases. Only left and right hepatectomies performed using a MIV technique were included in this study. Primary outcome was the occurrence of complications using the Clavien-Dindo graded classification and the Comprehensive Complication Index during the first 3 months. Logistic regression analysis was used to identify risk factors for complications.

RESULTS

In all, 412 MIV donor hepatectomies were recorded including 164 left and 248 right hepatectomies. Surgical technique was either pure laparoscopy in 175 cases or hybrid approach in 237. Conversion into standard laparotomy was necessary in 17 donors (4.1%). None of the donors died. Also, 108 experienced 121 complications including 9.4% of severe (Clavien-Dindo 3-4) complications. Median Comprehensive Complication Index was 5.2.

CONCLUSIONS

This study shows favorable early postoperative outcomes in more than 400 MIV donor hepatectomy from 10 experienced centers. These results are comparable to those of benchmarking series of open standard donor hepatectomy.

Conceptual changes in small-for-size graft and small-for-size syndrome in living donor liver transplantation

Early series in living donor liver transplantation (LDLT) in adults demonstrated a lower safe limit of graft volume standard liver volume ratio 25%–45%. A subsequent worldwide large LDLT series proposed a 0.8 graft recipient weight ratio (GRWR) to define small-for-size graft (SFSG) in adult LDLT. Thereafter, researchers identified innate and inevitable factors including changes in liver volume during imaging studies and graft shrinkage due to perfusion solution. Although the definition of small-for-size syndrome (SFSS) advocated in the 2000s was mainly based on prolonged cholestasis and ascites output, the term SFSS was inadequate to describe clinical manifestations possibly caused by multiple factors. Thus, the term “early allograft dysfunction (EAD),” characterized by total bilirubin >10 mg/dL or coagulopathy with international normalized ratio >1.6 on day 7, has become prevalent to describe graft dysfunction including SFSS after LDLT. Although various efforts have been made to overcome EAD in LDLT, graft selection to maintain an expected GRWR >0.8 and full venous drainage, as well as inflow modulation using splenic artery ligation, have become standard in recent LDLT.

Older Donor Age Is a Risk Factor for Negative Outcomes After Adult Living Donor Liver Transplantation Using Small-for-Size Grafts

Adult-to-adult living donor liver transplantation (ALDLT) using small-for-size grafts (SFSGs), ie, a graft with a graft-to-recipient weight ratio (GRWR) <0.8%, has been a challenge that should be carefully dealt with, and risk factors in this category are unclear. Therefore, we aimed to examine the risk factors and outcomes of ALDLT using SFSGs over a 13-year period in 121 patients who had undergone their first ALDLT using SFSGs. Small-for-size syndrome (SFSS), early graft loss, and 1-year mortality were encountered in 21.6%, 14.9%, and 18.4% of patients, respectively. By multivariate analysis, older donor age (≥45 years) was an independent risk factor for SFSS (odds ratio [OR], 4.46; P = 0.004), early graft loss (OR, 4.11; P = 0.02), and 1-year mortality (OR, 3.76; P = 0.02). Child-Pugh C class recipients were associated with a higher risk of SFSS development (P = 0.013; OR, 7.44). Despite no significant difference between GRWR categories in the multivariate outcome analysis of the whole population, in the survival analysis of the 2 donor age groups, GRWR <0.6% was associated with significantly lower 1-year survival than the other GRWR categories in the younger donor group. Moreover, in the high final portal venous pressure (PVP) group (>15 mm Hg), younger ABO-compatible donors showed 100% 1-year survival with a significant difference from the group of other donors. Older donor age was an independent risk factor for SFSS, early graft loss, and 1-year mortality after ALDLT using SFSGs. GRWR should not be <0.6%, and PVP modulation is indicated when grafts from older or ABO-incompatible donors are used.

Impact of small-for-size liver grafts on medium-term and long-term graft survival in living donor liver transplantation: A meta-analysis

BACKGROUND

Small-for-size grafts (SFSGs) in living donor liver transplantation (LDLT) could optimize donor postoperative outcomes and also expand the potential donor pool. Evidence on whether SFSGs would affect medium-term and long-term recipient graft survival is lacking.

AIM

To evaluate the impact of small-for-size liver grafts on medium-term and long-term graft survival in adult to adult LDLT.

METHODS

A systematic review and meta-analysis were performed by searching eligible studies published before January 24, 2019 on PubMed, EMBASE, and Web of Science databases. The primary outcomes were 3-year and 5-year graft survival. Incidence of small-for-size syndrome and short term mortality were also extracted.

RESULTS

This meta-analysis is reported according to the guidelines of the PRISMA 2009 Statement. Seven retrospective observational studies with a total of 1821 LDLT recipients were included in the meta-analysis. SFSG is associated with significantly poorer medium-term graft survival. The pooled odds ratio for 3-year graft survival was 1.58 [95% confidence interval 1.10-2.29, P = 0.014]. On the other hand, pooled results of the studies showed that SFSG had no significant discriminatory effect on 5-year graft survival with an odds ratio of 1.31 (95% confidence interval 0.87-1.97, P = 0.199). Furthermore, incidence of small-for-size syndrome detected in recipients of SFSG ranged from 0-11.4% in the included studies.

CONCLUSION

SFSG is associated with inferior medium-term but not long-term graft survival. Comparable long-term graft survival based on liver graft size shows that smaller grafts could be accepted for LDLT with appropriate flow modulatory measures. Close follow-up for graft function is warranted within 3 years after liver transplantation.

Impact of small-for-size liver grafts on medium-term and long-term graft survival in living donor liver transplantation: A meta-analysis

BACKGROUND

Small-for-size grafts (SFSGs) in living donor liver transplantation (LDLT) could optimize donor postoperative outcomes and also expand the potential donor pool. Evidence on whether SFSGs would affect medium-term and long-term recipient graft survival is lacking.

AIM

To evaluate the impact of small-for-size liver grafts on medium-term and long-term graft survival in adult to adult LDLT.

METHODS

A systematic review and meta-analysis were performed by searching eligible studies published before January 24, 2019 on PubMed, EMBASE, and Web of Science databases. The primary outcomes were 3-year and 5-year graft survival. Incidence of small-for-size syndrome and short term mortality were also extracted.

RESULTS

This meta-analysis is reported according to the guidelines of the PRISMA 2009 Statement. Seven retrospective observational studies with a total of 1821 LDLT recipients were included in the meta-analysis. SFSG is associated with significantly poorer medium-term graft survival. The pooled odds ratio for 3-year graft survival was 1.58 [95% confidence interval 1.10-2.29, P = 0.014]. On the other hand, pooled results of the studies showed that SFSG had no significant discriminatory effect on 5-year graft survival with an odds ratio of 1.31 (95% confidence interval 0.87-1.97, P = 0.199). Furthermore, incidence of small-for-size syndrome detected in recipients of SFSG ranged from 0-11.4% in the included studies.

CONCLUSION

SFSG is associated with inferior medium-term but not long-term graft survival. Comparable long-term graft survival based on liver graft size shows that smaller grafts could be accepted for LDLT with appropriate flow modulatory measures. Close follow-up for graft function is warranted within 3 years after liver transplantation.

Cascade plasmapheresis as a desensitization strategy for patients undergoing ABO incompatible living donor liver transplantation (ABOi LDLT): A single center experience

BACKGROUND AND AIM

The reduction of antibody titres (AT's) to a safe level is essential pre-requisite for patients awaiting ABO-incompatible liver transplantation (ABOi LT). We report our experience of performing cascade plasmapheresis (CP) on 2 different apheresis platforms (COBE Spectra and Spectra Optia) as a desensitization strategy for patients undergoing ABOi LT in our centre.

METHODS

This retrospective observational study was conducted on patients who underwent CP included in the desensitization protocol for ABOi LDLT. CP/conventional TPE was performed (daily/alternate day with daily estimation of AT) until a target titre of ≤ 8 was achieved.

RESULTS

During the study period, 4 patients (mean age 46.7 years; 100% males) underwent desensitization for ABOi LDLT with baseline AT (combined IgM and IgG) ranging from 64 to 512. A total of 15 CP sessions (range 2 - 6) were performed with a median of 3.5 sessions/patient. Desensitization rate was 100%. Only 1 patient underwent conventional TPE in the post-transplant due to rise in AT level to 64 (post-operative day 8). Average post-operative length of stay was 49 days (range 30 - 105). None of the patients experienced any episode of rejection (repeat liver biopsy). On follow up (1 year), 2 patients were alive and doing well, while other 2 patients succumbed during their hospital stay due to sepsis.

CONCLUSION

In our limited experience, the use of CP was safe and effective desensitization strategy for patients undergoing ABOi LDLT.

Living donor liver transplantation: looking back at my 30 years of experience

Since I moved from the National Cancer Center to Shinshu University, I have been performing living donor liver transplantation (LDLT), which is the only way to save the life of patients with end-stage liver disease. In June 1990, we performed the first LDLT that case was the first successful case in Japan. The patient remains healthy and is enjoying a normal life still 28 years after the transplant. In 1993, we successfully performed adult-to-adult LDLT, which was the first successful case in the world. The patient enjoyed a normal life for 17 years until she died at 70 years of age. For small children, the left liver of adult donors is too large to close the abdomen. However, in adolescents or adults, even when the whole right liver is used, the volume of the graft is too small. The concept of the standard liver volume (SLV) has proven very important for this procedure and is calculated as follows: 706.2 × body surface area + 2.4. We proposed a method for evaluating the congestion of the liver by Doppler ultrasound. In addition, we devised the right lateral sector graft. Over the years, we have contributed to LDLT in many ways and published many papers. We feel that our findings are quite useful not only for LDLT but also for other hepatectomy procedures.

Anesthesia Management and Fluid Therapy in Right and Left Lobe Living Donor Hepatectomy

OBJECTIVE

Right lobe living donor hepatectomy poses a greater risk for the donor in relation to blood loss. The aims of this study were to compare anesthetic and intraoperative fluid management in right and left lateral segment living donor hepatectomy.

PATIENTS AND METHODS

The anesthesia records of living donor hepatectomy patients were retrospectively reviewed. Donor age and weight, anesthesia time, central venous pressure, blood loss, blood product transfusion, intravenous fluids used, doses of furosemide, and urine output were compared and analyzed between groups using the Mann Whitney U test.

RESULTS

Forty-six patients underwent living donor left lateral segment hepatectomy (Group I); while 31 patients underwent right lobe hepatectomy (Group II). The mean blood loss in Group II was significantly higher compared to Group I (118 ± 81 mL vs 68 ± 64 mL), but clinically such amount of blood loss was not high enough to affect the hemodynamics. The fluid management was therefore not meaningfully different between the two groups. No blood transfusions or colloid infusions were required for either group. Urine output, hemoglobin changes, blood urea nitrogen, and serum creatinine pre- and postoperatively were not significantly different between groups.

CONCLUSIONS

As long as blood loss is minimal, we found no difference in the anesthetic management and fluid replacements between right and left lateral segment living donor hepatectomy.

Readdressing the Middle Hepatic Vein in Right Lobe Liver Donation: Triangle of Safety

For equipoising donor safety and optimal recipient outcomes, we adopted an algorithmic "triangle of safety" approach to retrieve 3 types of right lobe liver grafts (RLGs), namely, the modified extended right lobe graft (MERLG), the partial right lobe graft (PRLG), and the modified right lobe graft (MRLG). Reconstruction to achieve a single wide anterior sector outflow was ensured in all patients. We present donor and recipient outcomes based on our approach in 665 right lobe (RL) living donor liver transplantations (LDLTs) performed from January 2013 to August 2015. There were 347 patients who received a MERLG, 117 who received a PRLG, and 201 who received a MRLG. A right lobe graft (RLG) with a middle hepatic vein was retrieved only in 3 out of 18 donors with steatosis >10%. Cold ischemia time was significantly more and remnant volume was less in the MRLG group. Of the donors, 29.3% had complications (26% Clavien-Dindo grade I, II) with no statistically significant difference among the groups. The Model for End-Stage Liver Disease score was higher in the MERLG group. There were 34 out of 39 with a graft-to-recipient weight ratio (GRWR) of <0.7% who received a MERLG with inflow modulation. Out of 4 patients who developed small-for-size syndrome in this group, 2 died. The 90-day patient survival rate was similar among different GRWRs and types of RLG. In conclusion, a selective and tailored approach for RL donor hepatectomy based on optimal functional volume and metabolic demands not only addresses the key issue of double equipoise in LDLT but also creates a safe path for extending the limits.

Portal venous velocity affects liver regeneration after right lobe living donor hepatectomy

OBJECTIVES

We investigated whether chronological changes in portal flow and clinical factors play a role in the liver regeneration (LR) process after right donor-hepatectomy.

MATERIALS AND METHODS

Participants in this prospective study comprised 58 donors who underwent right donor-hepatectomy during the period February 2014 to February 2015 at a single medical institution. LR was estimated using two equations: remnant left liver (RLL) growth (%) and liver volumetric recovery (LVR) (%). Donors were classified into an excellent regeneration (ER) group or a moderate regeneration (MR) group based on how their LR on postoperative day 7 compared to the median value.

RESULTS

Multivariate analysis revealed that low residual liver volume (OR = .569, 95% CI: .367- .882) and high portal venous velocity in the immediate postoperative period (OR = 1.220, 95% CI: 1.001-1.488) were significant predictors of LR using the RLL growth equation; high portal venous velocity in the immediate postoperative period (OR = 1.325, 95% CI: 1.081-1.622) was a significant predictor of LR using the LVR equation. Based on the two equations, long-term LR was significantly greater in the ER group than in the MR group (p < .001).

CONCLUSION

Portal venous velocity in the immediate postoperative period was an important factor in LR. The critical time for short-term LR is postoperative day 7; it is associated with long-term LR in donor-hepatectomy.

Randomized trial on extended versus modified right lobe grafts in living donor liver transplantation

Despite advances in the practice of living donor liver transplantation (LDLT), the optimum surgical approach with respect to the middle hepatic vein (MHV) in right lobe LDLT remains undefined. We designed a randomized trial to compare the early postoperative outcomes in recipients and donors between extended right lobe grafts (ERGs; transection plane was maintained to the left of MHV and division of MHV performed beyond the segment VIII vein) and modified right lobe grafts (MRGs; transection plane was maintained to the right of MHV; the segment V and VIII drainage was reconstructed using a conduit of recipient portal vein). Eligible patients (n = 86) were prospectively randomized into the ERG arm (n = 43) and the MRG arm (n = 43) at the beginning of donor hepatectomy. The primary endpoint considered in this equivalence trial was patency of the MHV or the reconstructed "neo-MHV" in the recipient. The secondary endpoints included biochemical parameters, postoperative complications, mortality in recipients as well as donors and volume regeneration of remnant liver in donors, measured at 2 months. The patency of the MHV was comparable in the ERG and MRG arms (90.7% versus 81.4%; difference, 9.3%; 95% confidence interval [CI], -5.8 to 24.4; z score, 1.245; P = 0.21). Volume regeneration of the remnant liver in donors was significantly better in the MRG arm (111.3% versus 87.3%; mean difference, 24%; 95% CI, 14.6-33.3; P < 0.001). The remaining secondary endpoints in donors and recipients were similar between the 2 arms. To conclude, MRG with reconstructed neo-MHV has comparable patency to native MHV in ERG and confers equivalent graft outflow in the recipient. Furthermore, it allows better remnant liver regeneration in the donor at 2 months. Liver Transplantation 24 888-896 2018 AASLD.

Living Donor Liver Transplantation: Technical Innovations

Living donor liver transplantation (LDLT) has found a place to serve the end-stage liver disease community as the donor safety and recipient suitability has been elucidated. Donor safety is of paramount importance and transplant programs must continue endeavors to maintain the highest possible standards. At the same time, adequacy of grafts based on recipient clinical status via their model for end-stage liver disease (MELD) score and volumetric studies to achieve a GRBWR >0.8, along with special attention to anatomic tailoring and portal venous flow optimization are necessary for successful transplantation. Technical innovations have improved sequentially the utility and availability of LDLT.

Accuracy of preoperative CT liver volumetry in living donor hepatectomy and its clinical implications

Background

An accurate preoperative volumetric assessment of donor liver is essential for successful living donor liver transplant by ensuring adequate remnant and graft recipient weight ratio (GRWR).

Methods

The study cohort consisted of 744 right lobe (RL), 65 left lobe (LL) and 33 left lateral sector (LLS) grafts from July 2010 to January 2014. A semi-automated interactive commercial software called AW Volume share 6 was used for volumetry. Bland Altman plot was used for assessing the agreement between estimated graft weight (EGW) and actual graft weight (AGW).

Results

There was no statistically significant difference between EGW and AGW for RL graft weight (722±134 vs. 717±126 gm; P=0.06). Although Bland Altman graph showed that 95% limits of agreement was more in LL (-164 to +110) than RL (-156 to +147) and LLS grafts (-137 to +239), CT scan significantly overestimated LL graft weight (EGW =460±118 gm vs. AGW =433±102 gm; P=0.003) and underestimated LLS graft weight (EGW =203±48 gm vs. AGW =254±49 gm; P<0.001).

Conclusions

CT volumetry overestimate LL graft and underestimate LLS graft weight. This should be factored in when selecting LL graft by taking higher GRWR.

Living Donor Liver Transplantation Using Small-for-Size Grafts: Does Size Really Matter?

BACKGROUND

In living donor liver transplantation (LDLT), graft-to-recipient weight ratio (GRWR) > 0.8% is perceived as the critical graft size. This lower limit of GRWR (0.8%) has been challenged over the last decade owing to the surgical refinements, especially related to inflow and outflow modulation techniques. Our aim was to compare the recipient outcome in small-for-size (GRWR < 0.8) versus normal-sized grafts (GRWR > 0.8) and to determine the risk factors for mortality when small-for-size grafts (SFSG) were used.

METHODS

Data of 200 transplant recipients and their donors were analyzed over a period of two years. Routine practice of harvesting middle hepatic vein (MHV) or reconstructing anterior sectoral veins into neo-MHV was followed during LDLT. Outcomes were compared in terms of mortality, hospital stay, ICU stay, and occurrence of various complications such as functional small-for-size syndrome (F-SFSS), hepatic artery thrombosis (HAT), early allograft dysfunction (EAD), portal vein thrombosis (PVT), and postoperative sepsis. A multivariate analysis was also done to determine the risk factors for mortality in both the groups.

RESULTS

Recipient and donor characteristics, intraoperative variables, and demographical data were comparable in both the groups (GRWR < 0.8 and GRWR ≥ 0.8). Postoperative 90-day mortality (15.5% vs. 22.85%), mean ICU stay (10 vs. 10.32 days), and mean hospital stay (21.4 vs. 20.76 days) were statistically similar in the groups. There was no difference in postoperative outcomes such as occurrence of SFSS, HAT, PVT, EAD, or sepsis between the groups. Thrombosis of MHV/reconstructed MHV was a risk factor for mortality in grafts with GRWR < 0.8 but not in those with GRWR > 0.8.

CONCLUSION

Graft survival after LDLT using a small-for-size right lobe graft (GRWR < 0.8%) is as good as with normal grafts. However, patency of anterior sectoral outflow by MHV or reconstructed MHV is crucial to maintain graft function when SFSG are used.

Laparoscopic donor hepatectomy

Laparoscopic liver resection has been applied to treat most indications for liver resection during the past two decades. According to the literature, patient numbers have increased exponentially as a result, and surgical difficulty has increased as well. In expert centers, laparoscopic anatomical hemihepatectomy and major liver resection more than 3 segments have become the acceptable treatment. Moreover, with surgical innovations and accumulated experience, living donor liver transplantation has become an established treatment choice for patients on the transplant waiting list. It is even considered an inevitable choice in regions with limited access to organs from deceased donors. However, significant morbidity and rare but catastrophic mortality are associated with donor hepatectomy and remain major concerns. Therefore, to decrease the incidence of complications, a minimally invasive approach in donor hepatectomy was adopted in the early 2000s. Initially, a minimally invasive approach was used for left lateral sectionectomy for pediatric liver transplant, then for laparoscopy-assisted hemihepatectomy and pure laparoscopic/robotic right donor hepatectomy, and more recently, for adult living donor liver transplantation. The extent of procedure complexity and potential complications depends on the approach and the size of the graft to be harvested. Early results from expert teams have seemed promising in terms of shortened donor recovery and improved perioperative outcomes. However, the combination of these two highly sophisticated surgical procedures raise more concerns about donor safety, especially with regard to unexpected events during the operation. A high level of evidence is very difficult to achieve in this highly specialized surgical practice with limited penetration. Therefore, an international registry has been suggested to determine the risks and benefits before the use of laparoscopic right donor hepatectomy spreads.

Fighting Mortality in the Waiting List: Liver Transplantation in North America, Europe, and Asia

Liver disease is a major cause of mortality worldwide. Liver transplantation (LT) is the most effective treatment for end stage liver disease. Available resources and social circumstances have led to different ways of implementing LT around the world. The experience with pediatric LT corroborates the hypothesis that a combination of surgical strategies can be beneficial. The goal of this manuscript is to describe the strategies used by LT centers in North America, Europe and Asia and how these strategies can be applied to reduce waitlist mortality and increase access to LT.

Assessing the Non-tumorous Liver: Implications for Patient Management and Surgical Therapy

INTRODUCTION

Hepatic resection is performed for various benign and malignant liver tumors. Over the last several decades, there have been improvements in the surgical technique and postoperative care of patients undergoing liver surgery. Despite this, liver failure following an extended hepatic resection remains a critical potential postoperative complication. Patients with underlying parenchymal liver diseases are at particular risk of liver failure due to impaired liver regeneration with an associated mortality risk as high as 60 to 90%. In addition, live donor liver transplantation requires a thorough presurgical assessment of the donor liver to minimize the risk of postoperative complications.

RESULTS AND CONCLUSION

Recently, cross-sectional imaging assessment of diffuse liver diseases has gained momentum due to its ability to provide both anatomical and functional assessments of normal and abnormal tissues. Various imaging techniques are being employed to assess diffuse liver diseases including magnetic resonance imaging (MRI), computed tomography (CT), and ultrasound (US). MRI has the ability to detect abnormal intracellular and molecular processes and tissue architecture. CT has a high spatial resolution, while US provides real-time imaging, is inexpensive, and readily available. We herein review current state-of-the-art techniques to assess the underlying non-tumorous liver. Specifically, we summarize current approaches to evaluating diffuse liver diseases including fatty liver alcoholic or non-alcoholic (NAFLD, AFLD), hepatic fibrosis (HF), and iron deposition (ID) with a focus on advanced imaging techniques for non-invasive assessment along with their implications for patient management. In addition, the role of and techniques to assess hepatic volume in hepatic surgery are discussed.