Minimum graft size for successful living donor liver transplantation

Liver transplantation using an otherwise-wasted partial liver resection graft

Liver transplantation represents a complex surgical procedure and serves as a curative treatment for patients presenting an acute or chronic end-stage liver disease, or carefully selected liver malignancy. A significant gap still exists between the number of available donor organs and potential recipients. The use of an otherwise-wasted resected liver lobe from patients with benign liver tumors is a new, albeit small, option to alleviate the allograft shortage. This review provides evidence that resected liver lobes may be used successfully in liver transplantation.

Role of intelligent/interactive qualitative and quantitative analysis-three-dimensional estimated model in donor-recipient size mismatch following deceased donor liver transplantation

BACKGROUND

Donor-recipient size mismatch (DRSM) is considered a crucial factor for poor outcomes in liver transplantation (LT) because of complications, such as massive intraoperative blood loss (IBL) and early allograft dysfunction (EAD). Liver volumetry is performed routinely in living donor LT, but rarely in deceased donor LT (DDLT), which amplifies the adverse effects of DRSM in DDLT. Due to the various shortcomings of traditional manual liver volumetry and formula methods, a feasible model based on intelligent/interactive qualitative and quantitative analysis-three-dimensional (IQQA-3D) for estimating the degree of DRSM is needed.

AIM

To identify benefits of IQQA-3D liver volumetry in DDLT and establish an estimation model to guide perioperative management.

METHODS

We retrospectively determined the accuracy of IQQA-3D liver volumetry for standard total liver volume (TLV) (sTLV) and established an estimation TLV (eTLV) index (eTLVi) model. Receiver operating characteristic (ROC) curves were drawn to detect the optimal cut-off values for predicting massive IBL and EAD in DDLT using donor sTLV to recipient sTLV (called sTLVi). The factors influencing the occurrence of massive IBL and EAD were explored through logistic regression analysis. Finally, the eTLVi model was compared with the sTLVi model through the ROC curve for verification.

RESULTS

A total of 133 patients were included in the analysis. The Changzheng formula was accurate for calculating donor sTLV (P = 0.083) but not for recipient sTLV (P = 0.036). Recipient eTLV calculated using IQQA-3D highly matched with recipient sTLV (P = 0.221). Alcoholic liver disease, gastrointestinal bleeding, and sTLVi > 1.24 were independent risk factors for massive IBL, and drug-induced liver failure was an independent protective factor for massive IBL. Male donor-female recipient combination, model for end-stage liver disease score, sTLVi ≤ 0.85, and sTLVi ≥ 1.32 were independent risk factors for EAD, and viral hepatitis was an independent protective factor for EAD. The overall survival of patients in the 0.85 < sTLVi < 1.32 group was better compared to the sTLVi ≤ 0.85 group and sTLVi ≥ 1.32 group (P < 0.001). There was no statistically significant difference in the area under the curve of the sTLVi model and IQQA-3D eTLVi model in the detection of massive IBL and EAD (all P > 0.05).

CONCLUSION

IQQA-3D eTLVi model has high accuracy in predicting massive IBL and EAD in DDLT. We should follow the guidance of the IQQA-3D eTLVi model in perioperative management.

Dual Graft Living Donor Liver Transplantation for High Acuity Patients: A Single-Center Experience

Background

The outcomes of dual graft living donor liver transplantation (DGLDLT) in high acuity patients remain underreported. The objective of this study was to report long-term outcomes from a single center in this select group of patients.

Methods

This was a retrospective review of patients who underwent DGLDLT between 2012 and 2017 (n = 10). High acuity patients were defined as patients with model for end stage liver disease (MELD) ≥30 or Child Pugh score ≥11. We looked at 90-day morbidity and mortality and 5-year overall survival (OS).

Results

The median MELD score and Child Pugh score were 30 (26.7-35) and 11 (11-11.2). The median recipient weight was 105 (95.2-113.7) and ranged from 82 to 132 kg. Out of 10 patients, 4 (40%) required perioperative renal replacement therapy, and 8 (80%) required hospital admission for optimization. The estimated graft to recipient weight ratio (GRWR) with right lobe graft alone was <0.8 in all patients, between 0.75 and 0.65 in 5 (50%) patients, and <0.65 in 5 (50%) patients. The 90-day mortality was 3/10 (30%), and there were 3/10 (30%) deaths during long-term follow-up. Among 155 high acuity patients, the 1-year OS with standard LDLT, standard LDLT with GRWR <0.8, and DGLDLT was 82%, 76%, and 58%, respectively (P = 0.123). With a median follow-up of 40.6 (1.9-74.4) months, the 5-year OS for DGLDLT was 50%.

Conclusion

The use of DGLDLT in high acuity patients should be prudent and low GRWR grafts should be considered a viable alternative in selected patients.

Expanding the living donor pool using domino liver transplantation: a systematic review

INTRODUCTION

To this day, a discrepancy exists between donor liver demand and supply. Domino liver transplantation (DLT) can contribute to increasing the number of donor livers available for transplantation.

METHODS

The design of this systematic review was based on the Preferred Reporting Items for Systematic Reviews (PRISMA). A qualitative analysis of included studies was performed. Primary outcomes were mortality and peri- and postoperative complications related to DLT.

RESULTS

Twelve studies met the inclusion criteria. All included studies showed that DLT outcomes were comparable to outcomes of deceased donor liver transplantation (DDLT) in terms of mortality and complications. One-year patient survival rate ranged from 66.7% to 100%. Re-transplantation rate varied from 0 to 12.5%. Most frequent complications were related to biliary (3.7%-37.5%), hepatic artery (1.6%-9.1%), portal vein (12.5-33.3%) and hepatic vein events (1.6%), recurrence of domino donor disease (3.3%-17.4%) and graft rejection (16.7%-37.7%). The quality of the evidence was rated as moderate according to the Newcastle-Ottawa scale (NOS).

CONCLUSION

DLT outcomes were similar to DDLT in terms of mortality and complications. Even though DLT will not solve the entire problem of organ shortage, transplant programs should always consider using this tool to maximize the availability of liver grafts.

Machine learning improves the accuracy of graft weight prediction in living donor liver transplantation

Precise graft weight (GW) estimation is essential for planning living donor liver transplantation to select grafts of adequate size for the recipient. This study aimed to investigate whether a machine-learning model can improve the accuracy of GW estimation. Data from 872 consecutive living donors of a left lateral sector, left lobe, or right lobe to adults or children for living-related liver transplantation were collected from January 2011 to December 2019. Supervised machine-learning models were trained (80% of observations) to predict GW using the following information: donor's age, sex, height, weight, and body mass index; graft type (left, right, or left lateral lobe); computed tomography estimated graft volume and total liver volume. Model performance was measured in a random independent set (20% of observations) and in an external validation cohort using the mean absolute error (MAE) and the mean absolute percentage error and compared with methods currently available for GW estimation. The best-performing machine-learning model showed an MAE value of 50 ± 62 g in predicting GW, with a mean error of 10.3%. These errors were significantly lower than those observed with alternative methods. In addition, 62% of predictions had errors <10%, whereas errors >15% were observed in only 18.4% of the cases compared with the 34.6% of the predictions obtained with the best alternative method ( p  < 0.001). The machine-learning model is made available as a web application ( http://graftweight.shinyapps.io/prediction ). Machine learning can improve the precision of GW estimation compared with currently available methods by reducing the frequency of significant errors. The coupling of anthropometric variables to the preoperatively estimated graft volume seems necessary to improve the accuracy of GW estimation.

The role of graft to recipient weight ratio on enhanced recovery of the recipient after living donor liver transplantation - A systematic review of the literature and expert panel recommendations

BACKGROUND

There continues to be debate about the lower limit of graft-to-recipient weight ratio (GRWR) for living donor liver transplant (LDLT).

OBJECTIVES

To identify the lower limit of GRWR compatible with enhanced recovery after living donor liver transplant and to provide international expert panel recommendations.

DATA SOURCES

Ovid MEDLINE, Embase, Scopus, Google Scholar, and Cochrane Central.

METHODS

Systematic review following PRISMA guidelines and recommendations using the GRADE approach derived from an international expert panel. Studies assessing how GRWR affects recipient outcomes such as small for size syndrome, other complications, patient and graft survival, and length of stay were included.

PROTOCOL REGISTRATION

CRD42021260794.

RESULTS

Twenty articles were included in the qualitative synthesis, and all were retrospective observational studies. There was heterogeneity in the definition of study cohorts and key outcome measures such as small-for-size syndrome. Most studies lacked risk adjustment given limited single-center sample size. GRWR of ≥ .8% is associated with enhanced recovery. Recipients of grafts with GRWR < .8%, however, were found to have similar outcomes as those with ≥ .8% when appropriate consideration is made for portal flow modulation and recipient illness severity.

CONCLUSIONS

GRWR ≥ .8% is often compatible with enhanced recovery, but grafts < .8% can be used in selected LDLT recipients with optimal donor-recipient selection, surgical technique, and perioperative management (Quality of Evidence; Low | Grade of Recommendation; Strong).

Shulan Estimation Model: A New Formula for Estimation of Standard Liver Volume In Chinese Adults

BACKGROUND

To establish a new and accurate model for standard liver volume (SLV) estimation and graft size prediction in liver transplantation for Chinese adults.

METHODS

In this study, the data of morphologic indices and liver volume (LV) were retrospectively obtained on 507 cadaveric liver transplantation donors between June 2017 and September 2020 in Shulan (Hangzhou) Hospital. Linear regression analysis was performed to evaluate the impact of each parameter and develop a new SLV formula. The new formula was then validated prospectively on 97 donors between October 2020 and June 2021, and the prediction accuracy was compared with previous formulas.

RESULTS

The average LV in all subjects was 1445.68 ± 309.94 mL. Body weight (BW) showing the strongest correlation (r = 0.453, P < .001). By stepwise multiple linear regression analysis, BW and age were the only 2 independent correlation factors for LV. Shulan estimation model derived: SLV (mL) = 13.266 × BW (kg) - 4.693 × age + 797.16 (R2 = 0.236, P < .001). In the validation cohort, our new model achieved no significant differences between the estimated SLV and the actual LV (P > .05), and showed the lowest mean percentage error of 0.33%. The proportions of estimated SLV within the actual LV ± 20%, ± 15%, and ± 10% percentage errors were 69.1%, 55.7%, and 40.2%, respectively.

DISCUSSION

The Shulan SLV estimation model predicted LV more accurately than previous formulas on Chinese adults, which could serve as a simple screening tool during the initial assessment of graft volume for potential donors.

Outcome of Extended Right Lobe Liver Transplantations

Split-liver transplantation offers a solution to the organ shortage problem. However, the outcomes of extended right lobe liver transplantation (ERLT) and whether it is a suitable alternative to full-size liver transplantation (FSLT) remain controversial. We compared the outcomes of ERLT and FSLT in adult recipients of 43,409 first deceased donor liver transplantations using Cox regression. We also analyzed 612 ERLT and 1224 FSLT 1:2 matched cases to identify factors that affect ERLT outcome. The risk of graft loss was significantly higher following ERLT than following FSLT during the first posttransplantation year in the matched and unmatched collective (hazard ratio [HR], 1.39 and 1.27 and P = 0.01 and 0.006, respectively). Every additional hour of cold ischemia time (CIT) increased the risk of 1-year graft loss by 10% in the ERLT group compared with only 3% in the FSLT group (P = 0.003 and <0.001, respectively). Importantly, the outcome of ERLT and FSLT did not differ significantly if the CIT was below 10 hours (HR, 0.71; P = 0.22). One-year graft and patient survival were lower in high-risk ERLT recipients with a Model for End-Stage Liver Disease (MELD) score of ≥20 (HR, 1.88; P = 0.03 and HR, 2.03; P = 0.02). In the male recipient-male donor combination, ERLT recipients had a higher risk of 1-year graft loss than FSLT recipients (HR, 2.44; P = 0.006). This was probably because of the significantly higher MELD score in ERLT recipients (P = 0.004). ERLT in adults is an adequate alternative to FSLT and offers an elegant solution to the problem of organ shortage as long as the cold storage is less than 10 hours and the recipient's MELD score is <20.

HPi: A Novel Parameter to Predict Graft-related Outcome in Adult Living Donor Liver Transplant

BACKGROUND

Portal hyperperfusion is frequently associated with early allograft dysfunction (EAD). It is imperative to identify patients who would require portal inflow modulation. We aimed to identify factors associated with hyperperfusion-related graft injury and develop a predictive index for the same.

METHODS

Prospectively maintained database was queried to identify 135 adult living donor liver transplant recipients between September 2016 and July 2020. According to the calculated sample size, 96 patients were randomly selected for "test cohort". The remaining 39 patients made the "validation cohort." EAD was defined according to the A2ALL study. "Hyperperfusion index (HPi)," defined as posttransplant portal pressure gradient (ΔPpost)/graft-to-recipient splenic volume ratio (GRSVR), was devised on the basis of laws of flow dynamics and regression analysis.

RESULTS

Overall, 40 patients (29.6%) had EAD, six 90-d mortalities (4.4%) were attributable to EAD. In the test cohort, EAD patients (n = 29, 30.2%) had lower GRSVR (1.00 versus 2.22, P < 0.001), higher ΔPpost (14.8 versus 11.9, P = 0.004), and HPi (20.89 versus 8.67, P < 0.001). Multivariate analysis revealed GRSVR, ΔPpost, and HPi as significant factors to predict EAD. Receiver operating characteristic determined cutoff of HPi ≥9.97 could predict EAD with sensitivity of 90% and specificity of 73% (F-score = 0.712). HPi ≥16.25 predicted 90-d mortality with sensitivity of 100% and specificity of 78.9%. Patients with higher HPi had delayed graft-related recovery. Non-EAD patients had a higher 1-y (96% versus 79%) and 2-y (88% versus 79%) survival. The cutoff of HPi was validated well in the validation cohort (F-score = 0.645) (Hosmer-Lemeshow test, P = 0.89).

CONCLUSIONS

While predicted GRSVR may help identify at-risk patients preoperatively, intraoperatively calculated HPi is more accurate in identifying patients who would require portal inflow modulation. Achieving an HPi below target cutoff significantly decreases the risk of EAD even in low-GRSVR patients.

The Landscape of Nondirected Living Liver Donation in the United States

BACKGROUND

Living donor liver transplants (LDLTs) including those from nondirected donors (NDDs) have increased during the past decade, and center-level variations in LDLTs have not yet been described. We sought to quantify changes in the volume of NDD transplants over time and variation in NDD volume between transplant centers. We further examined characteristics of living liver donors and identified factors potentially associated with receiving an NDD liver transplant.

METHODS

Using Scientific Registry of Transplant Recipients data between March 01, 2002, and December 31, 2020, we compared 173 NDDs with 5704 DLDs and 167 NDD recipients with 1153 waitlist candidates.

RESULTS

NDDs increased from 1 (0.4% of LDLTs) in 2002 to 58 (12% of LDLTs) in 2020. Of 150 transplant centers, 35 performed at least 1 NDD transplant. Compared with waitlist candidates, adult NDD recipients were less frequently males (39% versus 62%, P < 0.001), had a lower model for end-stage liver disease (16 versus 18, P = 0.01), and spent fewer days on the waitlist (173 versus 246, P = 0.02). Compared with waitlist candidates, pediatric NDD recipients were younger (50% versus 12% age <2 y, P < 0.001) and more often diagnosed with biliary atresia (66% versus 41%, P < 0.001). Compared with DLDs, NDDs were older (40 versus 35 y, P < 0.001), college educated (83% versus 64%, P < 0.001), White (92% versus 78%, P < 0.001), and more frequently donated left-lateral segment grafts (32.0% versus 14%, P < 0.001).

CONCLUSIONS

Liver NDD transplants continue to expand but remain concentrated at a few centers. Graft distribution favors female adults and pediatric patients with biliary atresia. Racial inequities in adult or pediatric center-level NDD graft distribution were not observed.

A new formula for estimation of standard liver volume using liver height and thoracic width

Purpose

Precise estimation of the standard liver volume (SLV) is crucial in decision making regarding major hepatectomy and living donor liver transplantation. This study aimed to propose an accurate and efficient formula for estimating the SLV in the Korean population.

Methods

We created a regression model for SLV estimation using a data set of 230 Korean patients with healthy livers. The proposed model was cross validated using a different data set of 37 patients with healthy livers. The total liver volume (TLV), except for the volume of liver blood vessels, was measured through computed tomography volumetry as the dependent variable. Various anthropometric variables, liver height (LH), thoracic width (TW), age, and sex (0, female and 1, male) were considered as candidates for independent variables. We conducted stepwise regression analysis to identify variables to be included in the proposed model.

Results

A new formula was established; SLV = −1,275 + 9.85 × body weight (BW, kg) + 19.95 × TW (cm) + 7.401 × LH (mm). The proposed formula showed the best performance among existing formulas over the cross-validation data set.

Conclusion

The proposed formula derived using BW, TW, and LH estimated the TLV in the cross-validation data set more accurately than existing formulas.

Immunogenetics of xenotransplantation

Xenotransplantation may become the highly desired solution to close the gap between the availability of donated organs and number of patients on the waiting list. In recent years, enormous progress has been made in the development of genetically engineered donor pigs. The introduced genetic modifications showed to be efficient in prolonging xenograft survival. In this review, we focus on the type of immune responses that may target xeno-organs after transplantation and promising immunogenetic modifications that show a beneficial effect in ameliorating or eliminating harmful xenogeneic immune responses. Increasing histocompatibility of xenografts by eliminating genetic discrepancies between species will pave their way into clinical application.

Standard Liver Volume-Predicting Formulae Derived From Normal Liver Volume in Children Under 18 Years of Age

Background: Standard liver volume (SLV) is important in risk assessment for major hepatectomy. We aimed to investigate the growth patterns of normal liver volume with age and body weight (BW) and summarize formulae for calculating SLV in children. Methods: Overall, 792 Chinese children (<18 years of age) with normal liver were enrolled. Liver volumes were measured using computed tomography. Correlations between liver volume and BW, body height (BH), and body surface area (BSA) were analyzed. New SLV formulae were selected from different regression models; they were assessed by multicentral validations and were compared. Results: The growth patterns of liver volume with age (1 day-18 years) and BW (2-78 kg) were summarized. The volume grows from a median of 139 ml (111.5-153.6 in newborn) to 1180.5 ml (1043-1303.1 at 16-18 years). Liver volume was significantly correlated with BW (r = 0.95, P < 0.001), BH (r = 0.92, P < 0.001), and BSA (r = 0.96, P < 0.001). The effect of sex on liver volume increases with BW, and BW of 20 kg was identified as the optimal cutoff value. The recommended SLV formulae were BW≤20 kg: SLV = 707.12 × BSA ^1.09; BW>20 kg, males: SLV = 691.90 × BSA ^1.06; females: SLV = 663.19 × BSA ^1.04. Conclusions: We summarized the growth patterns of liver volume and provided formulae predicting SLV in Chinese children, which is useful in assessing the safety of major hepatectomies.

Our Living Donor Protocol for Liver Transplant: A SingleCenter Experience

OBJECTIVES

The shortage of deceased donor organs is a limiting factor in transplant. The growing discrepancy between the wait list demand versus the supply of deceased donor organs has created an incentive for consideration of living donor liver transplant as an alternative. Here, we describe our evaluation process and donor complications.

MATERIALS AND METHODS

Since 1988, we have performed 659 (449 living donor and 210 deceased donor) liver transplants. The most important evaluation criteria is the relationship between donor and recipient, and we require thatthe donor must be related to the recipient. The evaluation protocol has 5 stages. Donor complications were defined as simple, moderate, and severe.

RESULTS

We retrospectively investigated data for 1387 candidates, and 938 (67.7%) were rejected; subsequently, 449 living donor liver transplants were performed. There were no complications in 398 of the donors (88.7%). Total complication rate was 11.3%. Simple complications were seen in 31 patients (6.9%). Moderate complications were seen in 19 patients (4.2%). We had only 1 severe complication, ie, organ failure from unspecified liver necrosis, which resulted in death.

CONCLUSIONS

The relationship between donor and recipient and donor safety should be the primary focus for living donor liver transplant. Donor selection should be made carefully to minimize complications and provide adequately functional grafts.

Prediction of liver regeneration in recipients after living-donor liver transplantation in using preoperative CT texture analysis and clinical features

PURPOSE

The aim of the study is to predict the rate of liver regeneration in recipients after living-donor liver transplantation using preoperative CT texture and shape analysis of the future graft.

METHODS

102 donor-recipient pairs who underwent living-donor liver transplantation using right lobe grafts were retrospectively included. We semi-automatically segmented the future graft from preoperative CT. The volume of the future graft (LV_pre) was measured, and texture and shape analyses were performed. The graft liver was segmented from postoperative follow-up CT and the volume of the graft (LV_post) was measured. The regeneration index was defined by the following equation: [(LV_post-LV_pre)/LV_pre] × 100(%). We performed a stepwise, multivariate linear regression analysis to investigate the association between clinical, texture and shape parameters and the RI and to make the best-fit predictive model.

RESULTS

The mean regeneration index was 47.5 ± 38.6%. In univariate analysis, the volume of the future graft, energy, effective diameter, surface area, sphericity, roundness_m, compactness1, and grey-level co-occurrence matrix contrast as well as several clinical parameters were significantly associated with the regeneration index (p < 0.05). The best-fit predictive model for the regeneration index made by multivariate analysis was as follows: Regeneration index (%) = 127.020-0.367 × effective diameter - 1.827 × roundness_m + 47.371 × recipient body surface area (m²) + 12.041 × log(recipient white blood cell count) (× 10³/μL)+ 18.034 (if the donor was female).

CONCLUSION

The effective diameter and roundness_m of the future graft were associated with liver regeneration. Preoperative CT texture analysis of future grafts can be useful for predicting liver regeneration in recipients after living-donor liver transplantation.

Robotic, laparoscopic or open hemihepatectomy for giant liver haemangiomas over 10 cm in diameter

Background

To evaluate the clinical efficacy of robotic, laparoscopic, and open hemihepatectomy for giant liver haemangiomas.

Methods

From April 2011 to April 2017, consecutive patients who underwent hemihepatectomy for giant liver haemangiomas were included in this study. According to the type of operation, these patients were divided into the robotic hemihepatectomy (RH) group, the laparoscopic hemihepatectomy (LH) group, and the open hemihepatectomy (OH) group. The perioperative and short-term postoperative outcomes were compared among the three groups. The study was reported following the STROCSS criteria.

Results

There were no significant differences in age, sex, tumour location, body surface area (BSA), future liver remnant volume (FLR), standard liver volume (SLV), liver haemangioma volume, FLR/SLV, resected normal liver volume/resected volume, hepatic disease, rates of blood transfusion, liver function after 24 h of surgery, operative morbidity and mortality among the three groups. Compared with patients in the RH group (n = 19) and the LH group (n = 13), patients in the OH group (n = 25) had a significantly longer postoperative hospital stay (P < 0.05), time to oral intake (P < 0.05), and time to get-out-of-bed (P < 0.05); a higher VAS score after 24 h of surgery (P < 0.05); and a shorter operative time (P < 0.05). There were no significant differences in these postoperative outcomes (P>0.05) between the RH group and the LH group. When the setup time in the RH group was excluded, the operative time in the RH group was significantly shorter than that in the LH group (P<0.05). There was no significant difference in the operative time between the RH group and the OH group (P>0.05). The amount of intraoperative blood loss in the RH group was the lowest among the three groups (P<0.05), and the amount of intraoperative blood loss in the LH group was less than that in the OH group (P<0.05).

Conclusion

Robotic and laparoscopic hemihepatectomies were associated with less intraoperative blood loss,better postoperative recovery and lower pain score. Compared with laparoscopic hemihepatectomy, robotic hemihepatectomy was associated with significantly less intraoperative blood loss and a shorter operative time.

The Risk of Going Small: Lowering GRWR and Overcoming Small-For-Size Syndrome in Adult Living Donor Liver Transplantation

OBJECTIVE

The aim of this study was to determine the outcomes of living donor liver transplantation (LDLT) according to various graft-to-recipient weight ratio (GRWR).

BACKGROUND

The standard GRWR in LDLT is >0.8%. Our center accepted predicted GRWR ≥0.6% in selected patients.

METHODS

Data from patients who underwent LDLT from 2001 to 2017 were included. Patients were stratified according to actual GRWR (Group 1:GRWR ≤0.6%; Group 2: 0.6%<GRWR≤ 0.8%; Group 3:GRWR >0.8%).

RESULTS

There were 545 LDLT (group 1 = 39; group 2 = 159; group 3 = 347) performed. Pretransplant predicted GRWR showed good correlation to actual GRWR (R = 0.834) and these figures differed within a ± 10%margin (P = 0.034) using an equivalence test. There were more left lobe grafts in group 1 (33.3%) than group 2 (10.7%) and 3 (2.9%). Median donor age was <35 years and steatosis >10% was rare.There was no difference in postoperative complication, vascular and biliary complication rate between groups. Over one-fifth (20.5%) of group 1 patients required portal flow modulation (PFM) and was higher than group 2 (3.1%) and group 3 (4%) (P = 0.001). Twenty-six patients developed small-for-size syndrome (SFSS): 5 of 39 (12.8%) in group 1 and 21 of 159 (13.2%) in group 2 and none in group 3 (P < 0.001). There were 2 hospital mortalities; otherwise, the remaining patients [24/26 (92.3%)] survive with a functional liver graft. The 5-year graft survival rates were 85.4% versus 87.8% versus 84.7% for group 1, 2, and 3, respectively (P = 0.718). GRWR did not predict worse survivals in multivariable analysis.

CONCLUSIONS

Graft size in LDLT can be lowered to 0.6% after careful recipient selection, with low incidence of SFSS and excellent outcomes. Accurate graft weight prediction, donor-recipient matching, meticulous surgical techniques, appropriate use of PFM, and vigilant perioperative care is important to the success of such approach.

Dual graft living donor liver transplantation - a case report

Background

Living donor liver transplantation (LDLT) has emerged as an equally viable option to deceased donor liver transplant for treating end stage liver disease patients. Optimising the recipient outcome without compromising donor safety is the primary goal of LDLT. Achieving the adequate graft to recipient weight ratio (GRWR) is important to prevent small for size syndrome which is an uncommon but potentially lethal complication of LDLT.

Case presentation

Here we describe a case of successful dual lobe liver transplant for a 32 years old patient with ethanol related end stage liver disease. A right lobe graft without middle hepatic vein and another left lateral sector graft were transplanted successfully. Recipient and both donors recovered uneventfully.

Conclusion

Dual lobe liver transplant is a feasible strategy to achieve adequate GRWR without compromising donor safety.

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.

Application of 3-Dimensional Printing in Pediatric Living Donor Liver Transplantation: A Single-Center Experience

Three-dimensional (3D) printing has been used to support organ transplantations. However, whether it helps remains unclear. This study aimed to present and assess the application of 3D-printed liver models in pediatric living donor liver transplantation (LDLT). The 3D images were printed to touchable liver models with transparent liver parenchyma, specifically colored hepatic vessels, and biliary structures. A total of 30 consecutive recipients were enrolled in the study: 10 were operated on with the support of 3D printing (3D-printing group) and 20 (control group) were operated on without it. Detailed photographs and data of the cases in the 3D-printing group were presented. One patient underwent auxiliary partial orthotopic liver transplantation using the left lobe graft, in which the abdominal cavity model was also printed to test whether the planned graft fit the recipient's abdominal cavity. The 3D-printed models facilitated surgical planning and procedures, particularly in the management of hepatic veins and in the prevention of large-for-size syndrome. The operative time of donors in the 3D-printing group was significantly shorter compared with the control group (2.3 ± 0.4 versus 3.0 ± 0.4 hours; P < 0.001). Inpatient costs for donors in the 3D-printing group were 17.1% lower than those in the control group (34.6 ± 6.6 versus 41.7 ± 10.4 thousand ¥; P = 0.03). In conclusion, in small infants and complicated pediatric LDLT patients, 3D-printed models can help minimize the risk of large-for-size syndrome and graft reduction. The 3D-printed models may be conducive to liver graft procurement and intraoperative assistance in pediatric LDLT.

Should We Have Blind Faith in Liver Volumetry?

Introduction: Liver volumetry is a routine procedure performed before major hepatectomy or living donor liver transplantation (LDLT) to anticipate the remnant liver volume and prevent liver failure. However, many parameters may impact its accuracy and no large-scale studies have evaluated inter-rater variabilities. We aimed to determine the reliability of volumetric assessments for whole organs in deceased-donor liver transplantations (DDLT) and partial organs in LDLT settings. Patients & Methods: Eight operators (four surgeons + four radiologists) analysed 30 preoperative CT scans (15 whole cirrhotic livers in the DDLT group + 15 partial healthy grafts in the LDLT group), using five software systems. The computed volumes were compared with liver weight; liver density being considered as1. Results: Inter-rater and inter-software concordances were excellent with coefficients of correlation >0.9. However, calculations overestimated the real volumes in 25 cases by a mean of 249 ± 206 [14-771] cc in the DDLT group and 138 ± 92cc [39-375] in the LDLT group. The mean calculations were significantly higher than liver weights in the LDLT group only (p=0.04). The radiologists overestimated the surgeons’ assessment in 24 cases, the differences exceeding 6% in some cases. The type of software used significantly impacted results in the DDLTgroup. Conclusions: Despite its unanimously recognised utility, we highlight significant discrepancies between estimated and real liver volumes. The global overestimation may lead to leave of too small remnant liver, with potentially dramatic consequences. In case of border-line estimations, we recommend a repetition of the evaluation by another operator (surgeon + radiologist working in concert).

Xenogeneic Heterotopic Auxiliary Liver transplantation (XHALT) promotes native liver regeneration in a Post-Hepatectomy Liver failure model

The liver’s regenerative capacity is unique, but too small a segment can overwhelm its ability to simultaneously regenerate and support the host, resulting in liver dysfunction and death. Here we tested a temporary Xenogeneic Heterotopic Auxiliary Liver Transplant (XHALT) from Gal-KO miniature swine in a baboon model of Post-Hepatectomy Liver Failure (PHLF) by 90%- hepatectomy. Immunosuppression consisted of CVF, ATG, FK 506 and steroids. 90%-hepatectomized animals died within 4–5 days with the clinical picture of PHLF, (high LFTs and bilirubin, ascites, encephalopathy and coagulopathy). The 10% remnants had macroscopic and histological evidence of severe steatosis and absence of hepatocyte replication. In contrast, the addition of XHALT prolonged survival up to 11 days, with the cause of death being sepsis, rather than liver failure. The remnant liver appeared grossly normal, and on histology, there was no evidence of fatty infiltration, but there was pronounced Ki-67 staining. In conclusion, temporary auxiliary xenografts have the potential to support a small for size liver graft while it grows to adequate size or provide an opportunity for organ recovery in acute liver failure.

How small is TOO small? New liver constraint is needed- Proton therapy of hepatocellular carcinoma patients with small normal liver

PURPOSE

This study evaluated the outcomes of hepatocellular carcinoma (HCC) patients with small normal liver volume (NLV) treated with proton beam therapy (PBT) and introduced estimated standard liver volume (eSLV) as a new constraint.

MATERIALS AND METHODS

HCC patients with NLV < 800 cm3 and no distant metastasis who received treatment in our proton center were included. The doses of PBT were mainly 72.6 Gray equivalents (GyE) in 22 fractions and 66 GyE in 10 fractions according to tumor locations. The Urata equation was used to calculate eSLV.

RESULTS

Twenty-two patients were treated between November 2015 and December 2016. The 1-year progression-free and overall survival rates were 40.4% and 81.8%, respectively. The 1-year in-field failure-free rate was 95.5%. NLV ranged from 483.9 to 795.8 cm3 (median = 673.8 cm3), eSLV ranged from 889.3 to 1290.0 cm3 (median = 1104.5 cm3), and the resulting NLV/eSLV ratio ranged from 44.3 to 81.2% (median = 57.7%). Non-irradiated liver volume (NILV) ranged from 232.9 to 531.6 cm3 (median = 391.2 cm3). The NILV/eSLV ratio ranged from 21.2 to 48.0% (median = 33.3%). NLV in the patients who received <30 GyE (rV30) ranged from 319.1 to 633.3 cm3 (median = 488.2 cm3), and their rV30/eSLV ratio ranged from 30.7 to 58.0%. None of our patients developed liver failure. One patient with initial abnormal liver enzyme levels developed non-classic radiation-induced liver disease (RILD).

CONCLUSION

From the viewpoint of minimal liver toxicity occurring in our patients with NLV < 800 cm3, conventional liver constraints involving the use of absolute volume could not accurately predict the risk of RILD. It is reasonable to start using individualized constraints with eSLV for HCC patients undergoing PBT. According to the study results, an NILV/eSLV ratio of >20% and an rV30/eSLV ratio of >30% are acceptable.

Estimation of Standard Liver Volume Using CT Volume, Body Composition, and Abdominal Geometry Measurements

PURPOSE

The present study developed formulas for estimation of standard liver volume (SLV) with high accuracy for the Korean population.

MATERIALS AND METHODS

SLV estimation formulas were established using gender-balanced and gender-unbalanced measurements of anthropometric variables, body composition variables, and abdominal geometry of healthy Koreans (n=790). Total liver volume excluding blood volume, was measured based on CT volumetry.

RESULTS

SLV estimation formulas as preferred in various conditions of data availability were suggested in the present study. The suggested SLV estimation formulas in the present study were found superior to existing formulas, with an increased accuracy of 4.0-217.5 mL for absolute error and 0.2-18.7% for percentage of absolute error.

CONCLUSION

SLV estimation formulas using gender-balanced measurements showed better performance than those using gender-unbalanced measurements. Inclusion of body composition and abdominal geometry variables contributed to improved performance of SLV estimation.

Living Donor Liver Transplantation for Patients Older Than Age 70 Years: A Single-Center Experience

Over the past two decades, the age of liver transplantation (LT) recipients has been increasing. We reviewed our experience with LT for patients aged ≥70 years (range: 70-78 years) and investigated the feasibility of performing LT, especially living donor LT (LDLT), for older patients. We retrospectively reviewed the medical records of 25 patients (15 LDLT recipients, 10 deceased donor LT recipients) aged ≥70 years who underwent LT from January 2000 to April 2016. Their perioperative morbidity rate was 28.0%, and the in-hospital mortality rate was 16.0%; these results were comparable to those of matched patients in their 60s (n = 73; morbidity, p = 0.726; mortality, p = 0.816). For patients in their 70s, the 1- and 5-year patient survival rates were 84.0% and 69.8%, and the 1- and 5-year graft survival rates were 83.5% and 75.1%, respectively. Comparisons of patient and graft survival rates between matched patients in their 60s and 70s showed no statistically significant differences (patient survival, p = 0.372; graft survival, p = 0.183). Our experience suggests that patients aged ≥70 years should not be excluded from LT, or even LDLT, based solely on age and implies that careful selection of recipients and donors as well as meticulous surgical technique are necessary for successful results.

The International Liver Transplantation Society Living Donor Liver Transplant Recipient Guideline

Living donor liver transplantation (LDLT) has been increasingly embraced around the world as an important strategy to address the shortage of deceased donor livers. The aim of this guideline, approved by the International Liver Transplantation Society (ILTS), is to provide a collection of expert opinions, consensus, and best practices surrounding LDLT. Recommendations were developed from an analysis of the National Library of Medicine living donor transplantation indexed literature using the Grading of Recommendations Assessment, Development and Evaluation methodology. Writing was guided by the ILTS Policy on the Development and Use of Practice Guidelines (www.ilts.org). Intended for use by physicians, these recommendations support specific approaches to the diagnostic, therapeutic, and preventive aspects of care of living donor liver transplant recipients.

Compared to cadaveric liver transplantation, live donor LT (LDLT) is challenged by ethical, medical and surgical considerations, many of which are still unresolved. The aim of this guideline is to provide a collection of expert opinions, consensus, and best practices surrounding LDLT.

Adipose-derived mesenchymal stem cells promote liver regeneration and suppress rejection in small-for-size liver allograft

Adipose-derived mesenchymal stem cells (ADSCs) possess a liver regeneration capacity and immunosuppressive activity and hold promise in autologous cell-based technology. This study aimed to determine whether autologous ADSCs can improve outcomes in the rat reduced size liver transplantation model. Allogeneic 50% orthotopic liver transplantation followed by administration of autologous ADSCs delivered into the portal vein system was conducted in LEW donor rats and BN recipient rats with phosphate buffered solution (PBS) infusion used as the control. Liver grafts and recipient serum were obtained. We assessed histopathology, regeneration, apoptosis, serum liver enzymes, serum cytokines, and circulating regulatory T cells (Tregs) on postoperative day (POD) 7 and 14. It was found that ADSCs significantly reduced acute rejection and improved the allograft's survival times (median, 24days). Liver function, as assessed by the levels of alanine aminotransferase, aspartate aminotransferase, total bilirubin, as well as liver apoptosis was significantly alleviated in the ADSC group compared with the control group. In addition, ADSC therapy markedly promoted the expression of PCNA in the allograft. Furthermore, levels of interleukin (IL)-10 and transforming growth factor (TGF)-β1 were significantly elevated, whereas those of IL-2 and IL-17 levels were significantly reduced in the ADSC group when compared to the control group. Moreover, flow cytometry analysis revealed that peripheral Tregs had been significantly increased by the infusion of ADSCs. These results demonstrate that implanted autologous ADSCs improve allogeneic reduced size liver allograft outcomes by attenuating acute rejection and reducing inflammatory responses, as well as enhancing liver regeneration.

Small for size syndrome difficult dilemma: Lessons from 10 years single centre experience in living donor liver transplantation

AIM

To analyze the incidence, risk factors, prevention, treatment and outcome of small for size syndrome (SFSS) after living donor liver transplantation (LDLT).

METHODS

Through-out more than 10 years: During the period from April 2003 to the end of 2013, 174 adult-to-adults LDLT (A-ALDLT) had been performed at National Liver Institute, Menoufiya University, Shibin Elkoom, Egypt. We collected the data of those patients to do this cohort study that is a single-institution retrospective analysis of a prospectively collected database analyzing the incidence, risk factors, prevention, treatment and outcome of SFSS in a period started from the end of 2013 to the end of 2015. The median period of follow-up reached 40.50 m, range (0-144 m).

RESULTS

SFSS was diagnosed in 20 (11.5%) of our recipients. While extra-small graft [small for size graft (SFSG)], portal hypertension, steatosis and left lobe graft were significant predictors of SFSS in univariate analysis (P = 0.00, 0.04, 0.03, and 0.00 respectively); graft size was the only independent predictor of SFSS on multivariate analysis (P = 0.03). On the other hand, there was lower incidence of SFSS in patients with SFSG who underwent splenectomy [4/10 (40%) SFSS vs 3/7 (42.9%) no SFSS] but without statistical significance, However, there was none significant lower incidence of the syndrome in patients with right lobe (RL) graft when drainage of the right anterior and/or posterior liver sectors by middle hepatic vein, V5, V8, and/or right inferior vein was done [4/10 (28.6%) SFSS vs 52/152 (34.2%) no SFSS]. The 6-mo, 1-, 3-, 5-, 7- and 10-year survival in patients with SFSS were 30%, 30%, 25%, 25%, 25% and 25% respectively, while, the 6-mo, 1-, 3-, 5-, 7- and 10-year survival in patients without SFSS were 70.1%, 65.6%, 61.7%, 61%, 59.7%, and 59.7% respectively, with statistical significant difference (P = 0.00).

CONCLUSION

SFSG is the independent and main factor for occurrence of SFSS after A-ALDLT leading to poor outcome. However, the management of this catastrophe depends upon its prevention (i.e., selecting graft with proper size, splenectomy to decrease portal venous inflow, and improving hepatic vein outflow by reconstructing large draining veins of the graft).

Comparable Short- and Long-term Outcomes in Living Donor and Deceased Donor Liver Transplantations for Patients With Model for End-stage Liver Disease Scores ≥35 in a Hepatitis-B Endemic Area

OBJECTIVE

To evaluate if living donor liver transplantation (LDLT) should be offered to patients with Model for End-stage Liver Disease (MELD) scores ≥35.

BACKGROUND

No data was available to support LDLT of such patients.

METHODS

Data of 672 consecutive adult liver transplant recipients from 2005 to 2014 at our center were reviewed. Patients with MELD scores ≥35 were divided into the deceased donor liver transplantation (DDLT) group and the LDLT group and were compared. Univariate analysis was performed to identify risk factors affecting survival.

RESULTS

The LDLT group (n = 54) had younger (33 yrs vs 50 yrs, P < 0.001) and lighter (56 Kg vs 65 Kg, P = 0.004) donors, lighter grafts (627.5 g vs 1252.5 g, P < 0.001), lower graft-weight-to-recipient-standard-liver-volume rates (51.28% vs 99.76%, P < 0.001), shorter cold ischemic time (106.5 min vs 389 min, P < 0.001), and longer operation time (681.5 min vs 534 min, P < 0.001). The groups were comparable in postoperative complication, hospital mortality, and graft survival and patient survival at one year (88.9% vs 92.5%; 88.9% vs 94.7%), three years (87.0% vs 86.9%; 87.0% vs 88.8%), and five years (84.8% vs 81.8%; 84.8% vs 83.3%). Univariate analysis did not show inferior survival in LDLT recipients.

CONCLUSIONS

At centers with experience, the outcomes of LDLT can be comparable with those of DDLT even in patients with MELD scores ≥35. When donor risks and recipient benefits are fully considered and balanced, an MELD score ≥35 should not be a contraindication to LDLT. In Hong Kong, where most waitlisted patients have acute-on-chronic liver failure from hepatitis B, LDLT is a wise alternative to DDLT.

Living donor liver transplantation in patients weighing ≥100 kg: Low graft weight and obesity do not impact outcomes

Living donor liver transplantation (LDLT) in obese patients raises concerns with regards to obtaining grafts of "adequate" graft-to-recipient weight ratio (GRWR) and the impact of obesity on the outcomes of LDLT. LDLT outcomes in patients weighing ≥100 kg were compared with those weighing <100 kg. Patients weighing ≥100 kg were divided into 3 categories based on the GRWR of the grafts they received. Groups 1, 2, and 3 included patients with GRWR ≥0.8%, between 0.65% and 0.8%, and <0.65%, respectively. The 56 (6.5%) adult liver transplants were performed in patients weighing 100 kg or more. Except for higher mean body mass index (35.8 versus 25.2 kg/m² ; P value < 0.01) and grafts of lower GRWR in obese patients (0.74% versus 1.02%; P value < 0.01), all other parameters were similar between the 2 groups. Despite obesity and smaller grafts, the posttransplant outcomes such as day to normal bilirubin and international normalized ratio; infective, respiratory, and biliary complications; and hospital mortality were similar between the 2 groups. On comparing obese patients in the 3 GRWR categories, except for graft weight (985 versus 769 versus 646 g; P value < 0.01), all the pretransplant parameters were comparable. There was no significant difference in terms of graft function, postoperative morbidity, and hospital mortality between patients with grafts of normal GRWR and those with grafts of low and very low GRWR. Grafts of low GRWR give satisfactory results in obese patients undergoing LDLT and obesity does not adversely impact the outcome of LDLT. Liver Transplantation 23:35-42 2017 AASLD.

Size mismatch in liver transplantation

Size mismatch is an unique and inevitable but critical issue in live donor liver transplantation. Unmatched metabolic demand of recipient as well as physiologic mismatch aggravates the damage to liver graft, inevitably leading to graft failure on recipient. Also, an excessive resection of liver graft for better recipient outcome in live donor liver transplant may jeopardize the healthy donor well-being and even put donor life in danger. There is a fine balance between resected graft volume required to meet the recipient's metabolic demand and residual graft volume required for donor safety. The obvious clinical necessity of finding that balance has prompted a clinical need and promoted the improvement of knowledge and development of management strategies for size-mismatched transplants. The development of the size-matching methodology has significantly improved graft outcome and recipient survival in live donor liver transplants. On the other hand, the effect of size mismatch in cadaveric transplants has never been observed as being so pronounced. The importance of matching of the donor recipient size has been unrecognized in cadaveric liver transplant. In this review, we attempt to summarize the current most updated knowledge on the subject, particularly addressing the definition and complications of size-mismatched cadaveric liver transplant, as well as management strategies.

Minimum graft size calculated from preoperative recipient status in living donor liver transplantation

Small-for-size graft syndrome is an inevitable complication in living donor liver transplantation (LDLT). We hypothesized that graft weight (GW) measured after graft procurement is one of the variables predicting postoperative graft function. A total of 138 consecutive recipients of adult-to-adult LDLT between March 1999 and October 2014 were included in this study. We investigated the factors associated with small-for-size-associated graft loss (SAGL) to determine the GW required for each patient. Both preoperatively assessed and postoperatively obtained risk factors for SAGL were analyzed in univariate and multivariate logistic regression analysis. Twelve (8.8%) of the transplant recipients had SAGL. In multivariate logistic regression analyses using preoperatively assessed variables, the preoperative Model for End-Stage Liver Disease (MELD) score (P < 0.001) and actual GW/recipient standard liver volume (SLV) ratio (P = 0.008) were independent predictors of SAGL. The recommended graft volume by preoperative computed tomography volumetry was calculated as SLV × (1.616 × MELD + 0.344)/100/0.85 (mL) [MELD ≥ 18.2], or SLV × 0.35 (mL) [MELD < 18.2]. The required allograft volume in LDLT can be determined by the preoperative MELD score of the recipient, and patients with higher MELD scores require larger grafts or deceased donor whole liver transplant to avoid SAGL. Liver Transplantation 22 599-606 2016 AASLD.

Biliary complications in right lobe living donor liver transplantation

Living donor liver transplantation is an alternative to deceased donor liver transplantation in the face of insufficient deceased donor liver grafts. Unfortunately, the incidence of biliary complication after living donor liver transplantation is significantly higher than that after deceased donor liver transplantation using grafts from non-cardiac-death donations. The two most common biliary complications after living donor liver transplantation are bile leakage and biliary anastomotic stricture. Early treatment with endoscopic and interventional radiological approaches can achieve satisfactory outcomes. If treatment with these approaches fails, the salvage measure for prompt rectification will be surgical revision, which is now seldom performed. This paper also discusses risk factors in donor biliary anatomy that can affect recipients.

Living donor liver transplantation using dual grafts: Experience and lessons learned from cases worldwide

In living donor liver transplantation (LDLT), insufficient graft volume could result in small-for-size syndrome in recipients, whereas major liver donation predisposes the donor to a high risk of posthepatectomy liver failure. Dual graft LDLT is therefore introduced to obtain combined graft sufficiency. To date, 367 patients have been reported worldwide. We reviewed all the relevant literature, with a special focus on 43 case reports containing enough data to extract and analyze. A simple decision-making algorithm was developed. Dual graft LDLT is indicated when (1) a single donation is unacceptable due to graft-to-recipient size mismatch; (2) the future liver remnant is insufficient in the single donor after major resection; or (3) there is a significant underlying disorder or anatomical variation within the donor liver. The outcome of dual graft LDLT is reported to be comparable with that of single donor LDLT. Unilateral graft atrophy was found in 7 of the 43 patients, predominantly in the right-sided, heterotopic and initially smaller grafts. Technically, the heterotopic implantation and complex vascular reconstruction are the most demanding. Elaborate surgical planning and modification are needed. Ethical concerns about involving a second living donor need to be addressed. In conclusion, dual graft LDLT should be prudently performed in select cases by surgeons of proven expertise when single donation is unacceptable and a second living donor is available. The decision-making criteria need to be standardized. More surgical modification and clinical research are needed.

Durability of small-for-size living donor allografts

Our aim was to study the long-term outcomes of living donor liver transplantation using small-for-size (SFS) grafts. From July 2002 to July 2009, 233 patients received a right liver graft with a middle hepatic vein from a living donor in our center. Recipients were stratified according to the graft weight to recipient standard liver volume (GW/SLV) ratio into 4 groups: >50% (n = 89), >40% to 50% (n = 85), >35% to 40% (n = 38), and ≤ 35% (n = 21). They were compared in terms of graft survivals, biliary stricture rates, renal function in terms of estimated glomerular filtration rate (eGFR), platelet counts, and graft function in terms of serum bilirubin and international normalized ratio (INR). The 5-year graft survivals for patients with GW/SLV of >50%, >40% to 50%, >35% to 40% and ≤ 35% were 88.8%, 88.2%, 81.5%, and 81.0%, respectively. Transplantation for hepatocellular carcinoma affected graft survivals (P = 0.02), but graft size did not (P = 0.66). There were no differences in frequency of biliary stricture (21.3% versus 17.1% versus 21.1% versus 28.6%; P = 0.75). At each year after transplant, their platelet counts (P = 0.12-0.65), eGFR (P = 0.49-0.91), bilirubin (P = 0.14-0.51), and INR (P = 0.20-0.98) remained comparable. SFS grafts with GW/SLV ≤ 35% and >35% to 40% had comparable long-term outcomes with larger liver grafts. Graft size did not affect long-term graft survivals.

The impact of metabolic syndrome and prevalent liver disease on living donor liver transplantation: a pressing need to expand the pool

BACKGROUND AND AIMS

Organ shortage has been the ongoing obstacle to expanding liver transplantation worldwide. Living donor liver transplantation (LDLT) is hoped to improve this shortage. The aim of the present study is to analyze the impact of metabolic syndrome and prevalent liver disease on living donations.

METHODS

From July 2007 to May 2012, 1065 potential living donors were evaluated according to a stepwise evaluation protocol. The age of the worked-up donors ranged from 18 to 45 years.

RESULTS

Only 190 (18%) were accepted for donation, and 875 (82%) were rejected. In total, 265 (24.9%) potential donors were excluded because of either diabetes or a body mass index >28. Some potential donors were excluded at initial screening because of incompatible blood groups (115; 10.8%), social reasons (40; 3.8%), or elevated liver enzymes (9; 1%). Eighty-five (8%) donors were excluded because of positive hepatitis serology. Steatosis resulted in the exclusion of 84 (8%) donors. In addition, 80 (7.5%) potential donors were rejected because of variations in biliary anatomy, and 20 (2%) were rejected because of aberrant vascular anatomy. Rejection due to biliary-related aberrancy decreased significantly in the second half of our program (11 vs. 4%, p = 0.001). In total, 110 (10.3%) potential donors were rejected because of insufficient remnant volume (<30%) as determined by CT volumetry, whereas 24 (2.2%) were rejected because of a graft-to-recipient body weight ratio less than 0.8%.

CONCLUSION

Metabolic syndrome and viral hepatitis negatively impacted our living donor pool. Expanding the donor pool requires the implementation of new strategies.

The role of adult living donor liver transplantation and recent advances

Twenty years since the first cases were described, adult living donor liver transplantation (ALDLT) is now considered a valid option to expand the donor pool in view of the ongoing shortage of organs and the high waiting list mortality rate. Despite the rapid evolution and acceptance of this complex process of donation and transplantation in clinical practice, the indications, outcome, ethical considerations and quality and safety aspects continue to evolve based on new data from large cohort studies. This article reviews the surgical and clinical advances in the field of liver transplantation, focusing on technical refinements and discussing the issues that may lead to a further expansion of this complex surgical procedure and the role of ALDLT.

Transplantation of a 2-year-old deceased-donor liver to a 61-year-old male recipient

The suitable size of a graft is a key element in the success of liver transplantation. A small-for-size liver graft is very likely to sustain a significant degree of injury as a result of ischemia, preservation, reperfusion, and rejection. Usually, small-for-size grafts are a concern in living-donor liver transplantation rather than in deceased-donor liver transplantation. Here, we describe the successful transplantation of a liver from a 2-year-old deceased donor to a 61-year-old male recipient who suffered from liver failure related to hepatitis B. No report of successful deceased-donor liver transplantation with discrepancies between donor and recipient age and size to such an extent has been found in the literature. Despite unusually large discrepancies, with effort in minimizing the ischemic time, revised surgical techniques, and strong regenerative power of the "young" graft, the old patient's liver function gradually returned to normal. This again proves that the definition of a "suitable graft" evolves with time and experience.

Volumetric analysis and indocyanine green retention rate at 15 min as predictors of post-hepatectomy liver failure

OBJECTIVES

The actual future liver remnant (aFLR) is calculated as the ratio of remnant liver volume (RLV) to total functional liver volume (TFLV). The standardized future liver remnant (sFLR) is calculated as the ratio of RLV to standard liver volume (SLV). The aims of this study were to compare the aFLR with the sFLR and to determine criteria for safe hepatectomy using computed tomography volumetry and indocyanine green retention rate at 15 min (ICG R15).

METHODS

Medical records and volumetric measurements were obtained retrospectively for 81 patients who underwent right hemi-hepatectomy for malignant hepatic tumours from January 2010 to November 2013. The sFLR was compared with the aFLR, and a ratio of sFLR to ICG R15 as a predictor of postoperative hepatic function was established.

RESULTS

In patients without cirrhosis, the sFLR showed a stronger correlation with the total serum bilirubin level than the aFLR (R(2) = 0.499 versus R(2) = 0.239). Post-hepatectomy liver failure developed only in the group with an sFLR of <25%, regardless of ICG R15. In patients with cirrhosis, the aFLR and sFLR had no correlation with postoperative total serum bilirubin. An sFLR : ICG R15 ratio of >1.9 showed 66.7% sensitivity and 100% specificity.

CONCLUSIONS

Regardless of ICG R15, an sFLR of ≥ 25% in patients without cirrhosis, and an sFLR of ≥ 25% with an sFLR : ICG R15 ratio of >1.9 in patients with cirrhosis indicate acceptable levels of safety in major hepatectomy.