New prediction factors of small-for-size syndrome in living donor adult liver transplantation for chronic liver disease

Prediction and management of small-for-size syndrome in living donor liver transplantation

Small-for-size syndrome (SFSS) remains a critical challenge in living donor liver transplantation (LDLT), characterized by graft insufficiency due to inadequate liver volume, leading to significant postoperative morbidity and mortality. As the global adoption of LDLT increases, the ability to predict and manage SFSS has become paramount in optimizing recipient outcomes. This review provides a comprehensive examination of the pathophysiology, risk factors, and strategies for managing SFSS across the pre-, intra-, and postoperative phases. The pathophysiology of SFSS has evolved from being solely volume-based to incorporating portal hemodynamics, now recognized as small-for-flow syndrome. Key risk factors include donor-related parameters like age and graft volume, recipient-related factors such as MELD score and portal hypertension, and intraoperative factors related to venous outflow and portal inflow modulation. Current strategies to mitigate SFSS include careful graft selection based on graft-to-recipient weight ratio and liver volumetry, surgical techniques to optimize portal hemodynamics, and novel interventions such as splenic artery ligation and hemiportocaval shunts. Pharmacological agents like somatostatin and terlipressin have also shown promise in modulating portal pressure. Advances in 3D imaging and artificial intelligence-based volumetry further aid in preoperative planning. This review emphasizes the importance of a multifaceted approach to prevent and manage SFSS, advocating for standardized definitions and grading systems. Through an integrated approach to surgical techniques, hemodynamic monitoring, and perioperative management, significant strides can be made in improving the outcomes of LDLT recipients. Further research is necessary to refine these strategies and expand the application of LDLT, especially in challenging cases involving small-for-size grafts.

Graft inflow modulation in recipients with portal hypertension

The extended application of living donor liver transplantation (LDLT) has revealed the problem of graft size mismatching, potentially leading to the "small-for-size syndrome" (SFSS). SFSS is a rare dysfunction that may affect a partial liver graft, characterized by coagulopathy, cholestasis, ascites, and encephalopathy. A key role in the physiopathology of SFSS is played by portal hypertension (PHT) to which a small allograft is submitted after reperfusion, resulting in sinusoidal congestion and hemorrhage. Portal overflow injures the liver directly through nutrient excess, endothelial activation, and sinusoidal shear stress, and indirectly through arterial vasoconstriction. Thus, SFSS prevention relies not only on increasing graft volume (implementing the use of larger grafts or auxiliary/dual liver transplantation), but also on the control of the increased portal vein pressure (PVP) and portal vein flow (PVF). To this aim, surgical graft inflow modulation techniques (GIM) such as splenic artery ligation (SAL), splenectomy and hemiportocaval shunts, can be considered when an imbalance between the PVP and the hepatic arterial flow (HAF) is acknowledged. However, such strategies have their pros and cons, and a deep knowledge of the indications and complications is needed. Furthermore, pharmacological modulation has also been proposed. This review is aimed to update available literature on the current knowledge and strategies for modulating portal vein flow in LDLT.

Algorithmic Approach to Deranged Liver Functions After Transplantation

Liver transplant (LT) recipients require close follow-up with regular monitoring of the liver function tests (LFTs). Evaluation of deranged LFT should be individualized depending upon the time since LT, peri-operative events, clinical course, and any complications. These derangements can range from mild and asymptomatic to severe and symptomatic elevations requiring expedited personalized assessment and management. Pattern of LFT derangement (hepatocellular, cholestatic, or mixed), donor-recipient risk factors, timing after LT (post-operative, 1-12 months, and >12 months since LT) along with clinical context and symptomatology are important considerations before proceeding with the initial evaluation. Compliance to immunosuppression and drug interactions should be ascertained along with local epidemiology of infections. Essential initial evaluation must include an ultrasound abdomen with Doppler to rule out any structural causes such as biliary or vascular complications apart from focussed laboratory evaluation. Early allograft dysfunction, ischemia reperfusion injury, small-for-size syndrome, biliary leaks, hepatic artery, and portal vein thrombosis are usual culprits in the early post-operative period whereas viral hepatitis (acute or reactivation), opportunistic infections, and recurrence of the primary disease are more frequent in the later period. Graft rejection, biliary strictures, sepsis, and drug induced liver injury remain possible etiologies at all times points after LT. Initial evaluation algorithm must be customized based on history, clinical examination, risk factors, and pattern and severity of deranged LFT. Allograft rejection is a diagnosis of exclusion and requires liver biopsy to confirm and assess severity. Empirical treatment of rejection sans liver biopsy is discouraged.

Role of the portal system in liver regeneration: From molecular mechanisms to clinical management

The liver has a strong regenerative capacity that ensures patient recovery after hepatectomy and liver transplantation. The portal system plays a crucial role in the dual blood supply to the liver, making it a significant factor in hepatic function. Several surgical strategies, such as portal vein ligation, associating liver partition and portal vein ligation for staged hepatectomy, and dual vein embolization, have highlighted the portal system's importance in liver regeneration. Following hepatectomy or liver transplantation, the hemodynamic properties of the portal system change dramatically, triggering regeneration via shear stress and the induction of hypoxia. However, excessive portal hyperperfusion can harm the liver and negatively affect patient outcomes. Furthermore, as the importance of the gut-liver axis has gradually been revealed, the effect of metabolites and cytokines from gut microbes carried by portal blood on liver regeneration has been acknowledged. From these perspectives, this review outlines the molecular mechanisms of the portal system's role in liver regeneration and summarizes therapeutic strategies based on the portal system intervention to promote liver regeneration.

Preventing Small-for-size Syndrome in Living Donor Liver Transplantation: Guidelines From the ILTS-iLDLT-LTSI Consensus Conference

Small-for-size syndrome (SFSS) is a well-recognized complication following liver transplantation (LT), with up to 20% developing this following living donor LT (LDLT). Preventing SFSS involves consideration of factors before the surgical procedure, including donor and recipient selection, and factors during the surgical procedure, including adequate outflow reconstruction, graft portal inflow modulation, and management of portosystemic shunts. International Liver Transplantation Society, International Living Donor Liver Transplantation Group, and Liver Transplant Society of India Consensus Conference was convened in January 2023 to develop recommendations for the prediction and management of SFSS in LDLT. The format of the conference was based on the Grading of Recommendations, Assessment, Development, and Evaluation system. International experts in this field were allocated to 4 working groups (diagnosis, prevention, anesthesia, and critical care considerations, and management of established SFSS). The working groups prepared evidence-based recommendations to answer-specific questions considering the currently available literature. The working group members, independent panel, and conference attendees served as jury to edit and confirm the final recommendations presented at the end of the conference by each working group separately. This report presents the final statements and evidence-based recommendations provided by working group 2 that can be implemented to prevent SFSS in LDLT patients.

A systematic review of small for size syndrome after major hepatectomy and liver transplantation

BACKGROUND

Major hepatectomy (MH) and particular types of liver transplantation (LT) (reduced size graft, living-donor and split-liver transplantation) lead to a reduction in liver mass. As the portal venous return remains the same it results in a reciprocal and proportionate rise in portal venous pressure potentially resulting in small for size syndrome (SFSS). The aim of this study was to review the incidence, diagnosis and management of SFSS amongst recipients of LT and MH.

METHODS

A systematic review was performed in accordance with the 2010 Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) guidelines. The following terms were used to search PubMed, Embase and Cochrane Library in July 2019: ("major hepatectomy" or "liver resection" or "liver transplantation") AND ("small for size syndrome" or "post hepatectomy liver failure"). The primary outcome was a diagnosis of SFSS.

RESULTS

Twenty-four articles met the inclusion criteria and could be included in this review. In total 2728 patients were included of whom 316 (12%) patients met criteria for SFSS or post hepatectomy liver failure (PHLF). Of these, 31 (10%) fulfilled criteria for PHLF following MH. 8 of these patients developed intractable ascites alongside elevated portal venous pressure following MH indicative of SFSS.

CONCLUSION

SFSS is under-recognised following major hepatectomy and should be considered as an underlying cause of PHLF. Surgical and pharmacological therapies are available to reduce portal congestion and reverse SFSS.

Recipient Outcomes with Younger Donors Undergoing Living Donor Liver Transplantation

Introduction

The impact of donor age on liver transplantation is well known. Data on an appropriate donor age cut-off for living donor liver transplantation (LDLT) with a background of hepatitis C (HCV) is generally limited. The objective of this study was to determine whether limiting donor age to less than 35 years improved outcomes in patients with HCV-related end-stage liver disease (ESLD).

Methods

This was a retrospective review of 169 patients who underwent LDLT for HCV-related ESLD. The patients were divided into two groups based on whether they received grafts from donors ≤ 35 (Group 1) or > 35 (Group 2) years of age. Kaplan Meier curves were used to determine survival. Uni and multivariate analysis were performed to determine independent predictors of mortality.

Results

Mean donor age was 25.1 ± 5.2 and 40.1 ± 3.4 years (P < 0.0001). Early allograft dysfunction (EAD) was seen in 11.7% patients in Group 1 versus 29.6% in Group 2 (P = 0.02). A significant difference in mortality was present between the two groups, i.e., 33.3% versus 15.8% (P = 0.04). The estimated four-year overall survival (OS) was 78% and 64% (P = 0.03). Upon doing univariate analysis, the donor age (P = 0.04) and EAD (P = 0.006) were found to be significant variables for mortality. On multivariate analysis, EAD was the only independent predictor of mortality (Hazard ratio: 2.6; confidence interval: 1.1 - 5.8; P = 0.01).

Conclusion

Opting for younger donors (≤ 35 years) for HCV-related ESLD patients lowers the risk of EAD and improves overall survival.

Hemophagocytic syndrome after living donor liver transplantation: a case report with a review of the literature

Background

Hemophagocytic syndrome (HPS) is a rare and potentially fatal complication following liver transplantation.

Case presentation

A 63-year-old woman with decompensated liver cirrhosis secondary to hepatitis B virus infection underwent living donor liver transplantation using the right posterior section of her husband’s liver (graft volume, 581 g; 56.8% of the recipient’s standard liver volume). She developed small-for-size syndrome on postoperative day (POD) 7, and HPS was diagnosed on POD 12 by bone marrow aspiration (white blood cells, 300/μL; neutrophils, 30/μL). Given that she tested negative for viral (hepatitis B virus and cytomegalovirus) and bacterial infections, it was considered likely to be secondary HPS. Steroid pulse therapy was initiated, and her white blood cell count increased to 4290/μL on POD 15, indicating that her peripheral blood leukocytes had improved. There were no surgical complications, but the patient died of prolonged graft dysfunction with bacterial sepsis on POD 14.

Conclusions

We report a rare case of HPS occurring 2 weeks after living donor liver transplantation with a right posterior section graft, diagnosed early via bone marrow aspiration. This clinical course implies an association between HPS and graft dysfunction such as small-for-size syndrome. Further studies of the mechanism of hypercytokinemia-induced HPS are required to confirm the optimal treatment for HPS.

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).

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).

Graft inflow modulation in adult-to-adult living donor liver transplantation: A systematic review

INTRODUCTION

Small-for-size syndrome (SFSS) has an incidence between 0 and 43% in small-for-size graft (SFSG) adult living donor liver transplantation (LDLT). Portal hypertension following reperfusion and the hyperdynamic splanchnic state are reported as the major triggering factors of SFSS. Intra- and postoperative strategies to prevent or to reduce its onset are still under debate. We analyzed graft inflow modulation (GIM) during adult LDLT considering the indications, efficacy of the available techniques, changes in hemodynamics and outcomes.

MATERIALS AND METHODS

A systematic literature search was performed using PubMed, EMBASE, Scopus and the Cochrane Library Central. Treatment outcomes including in-hospital mortality and morbidity, re-transplantation rate, 1-, 3-, and 5-year patient overall survival and 1-, 3-, and 5-year graft survival rates, hepatic artery and portal vein flows and pressures before and after inflow modulation were analyzed.

RESULTS

From 563 articles, 12 studies dated between 2003 and 2014 fulfilled the selection criteria and were therefore included in the study. These comprised a total of 449 adult patients who underwent inflow modulation during adult-to-adult LDLT. Types of GIM described were splenic artery ligation, splenectomy, meso-caval shunt, spleno-renal shunt, portocaval shunt, and splenic artery embolization. Mortality and morbidity ranged between 0 and 33% and 17% and 70%, respectively. Re-transplantation rates ranged between 0% and 25%. GIM was associated with good survival for both graft and recipients, reaching an 84% actuarial rate at 5 years. Through the use of GIM, irrespective of the technique, a statistically significant reduction of PVF and PVP was obtained.

CONCLUSIONS

GIM is a safe and efficient technique to avoid or limit portal hyperperfusion, especially in cases of SFSG, decreasing overall morbidity and improving outcomes.

Small-for-Size Syndrome: Bridging the Gap Between Liver Transplantation and Graft Recovery

In living donor liver transplantation, optimal graft size is estimated from values like graft volume/standard liver volume and graft/recipient body weight ratio but the final functional hepatic mass is influenced by other donor and recipient factors. Grafts with insufficient functional hepatic mass can produce a life-threatening condition with rapidly progressive liver failure called small-for-size syndrome (SFSS). Diagnosis of SFSS requires careful surveillance for signs of inadequate hepatocellular function, residual portal hypertension, and systemic inflammation that suggest rapidly progressive liver failure. Early diagnosis, symptom control, and addressing the cause of SFSS may prevent the need for retransplantation. With increased attention to avoiding donor risk, intensivists will be confronted with more SFSS recipients. In this review, we aim to outline a systematic approach to the medical management of patients with SFSS by providing a concise synopsis of general supportive care—neurological, cardiovascular, and renal support, mechanical ventilation, nutritional support, infection control, and tailored immunosuppression—with an aim to avoid end-organ damage or death and a review of current interventions including liver support devices, portal flow modulating drugs, and other experimental interventions that aim to preserve existing hepatic mass and improve conditions for hepatic regeneration. We examine evidence for SFSS interventions to provide the reader with information that may assist in clinical decision making. Points of controversy in care are purposefully highlighted to identify areas where additional experimental work is still needed. A full understanding of the pathophysiology of SFSS and measures to support liver regeneration will guide effective management.

Exploring Portal Vein Hemodynamic Velocities as a Promising, Attractive Horizon for Small-for-Size Syndrome Prediction After Living-Donor Liver Transplantation: An Egyptian Center Study

BACKGROUND

Liver transplantation is the only definite treatment for patients with irreversible liver failure. This explored the impact of portal vein hemodynamic velocities on graft functions to determine the mean portal vein velocities that may increase small-for-size syndrome (SFSS) risk.

METHODS

The study was conducted with 123 cirrhotic patients who underwent living-donor liver transplantation (LDLT) at Kasr Alainy Hospital, Cairo, Egypt. Patients were submitted to full history, examination, pre-transplantation labs, and imaging. Intra-operative Doppler studies were performed after graft reperfusion. Post-operative (PO) Doppler was performed once a day over the first 2 weeks. Complete graft functions were obtained daily for patients.

RESULTS

PVV (portal vein velocities) declined gradually but significantly after LT (intra-operative), and PO PVV were significantly higher in the SFSS group. The best cut-off values for prediction of SFSS with the use of intra-operative (before, during, and after) post-anastomotic PVV were 55.5, 106, and 126.5 cm/s, respectively, and, for PO before and after anastomotic PVV, 48.6 and 71.1 cm/s, respectively. There was a significant positive correlation between PO mean PVV and mean alanine transferase, total bilirubin, and international normalized ratio.

CONCLUSIONS

PVV is a significant hemodynamic factor that influences graft functions. SFSS, which has a negative impact after LDLT, could be predicted by cut-off values for PVV, and therefore preventive measures such as splenectomy may be considered for its prevention.

Small for Size and Flow (SFSF) syndrome: An alternative description for posthepatectomy liver failure

Small for Size Syndrome (SFSS) syndrome is a recognizable clinical syndrome occurring in the presence of a reduced mass of liver, which is insufficient to maintain normal liver function. A definition has yet to be fully clarified, but it is a common clinical syndrome following partial liver transplantation and extended hepatectomy, which is characterized by postoperative liver dysfunction with prolonged cholestasis and coagulopathy, portal hypertension, and ascites. So far, this syndrome has been discussed with focus on the remnant size of the liver after partial liver transplantation or extended hepatectomy. However, the current viewpoints believe that the excessive flow of portal vein for the volume of the liver parenchyma leads to over-pressure, sinusoidal endothelial damages and haemorrhage. The new hypothesis declares that in both extended hepatectomy and partial liver transplantation, progression of Small for Size Syndrome is not determined only by the "size" of the liver graft or remnant, but by the hemodynamic parameters of the hepatic circulation, especially portal vein flow. Therefore, we suggest the term "Small for Size and Flow (SFSF)" for this syndrome. We believe that it is important for liver surgeons to know the pathogenesis and manifestation of this syndrome to react early enough preventing non-reversible tissue damages.

D-MELD, the Product of Donor Age and Preoperative MELD, Predicts Surgical Outcomes After Living Donor Liver Transplantation, Especially in the Recipients With HCV-positive and Smaller Grafts

BACKGROUND

Appropriate donor-recipient match has not been explored well in living-donor liver transplantation (LDLT) unlike deceased-donor liver transplantation. In this study, we evaluate the donor-recipient match using D-MELD (donor age × recipient Modified for End-stage Liver Disease [MELD] score) as a predictor of surgical outcomes in LDLT, paying attention to graft size and hepatitis C virus (HCV) status.

PATIENT AND METHODS

The 120 consecutive recipients who received adult-to-adult LDLT from March 2002 to December 2014 were divided into the two groups according to D-MELD score: D-MELD <1000 (low-D-MELD: n = 101) and D-MELD ≥1000 (high-D-MELD: n = 19).

RESULTS

The 90-day mortality rate was significantly higher in the high-DM group than in low-DM group: 36.8% versus 14.9% (P = .046). In the HCV-positive recipients, the 90-day mortality rate was significantly higher in high-DM group (n = 6) than in low-DM group (n = 37): 66.7% versus 13.5% (P = .012), and the 3-year survival rate was significantly lower in high-DM group than in the low-DM group: 33.3% versus 56.8% (P = .01). In the recipients with left graft, the 90-day mortality rate was significantly higher in the high-DM group (n = 8) than in the low-DM group (n = 41): 50% versus 14.6% (P = .044), and total bilirubin level on postoperative day 14 was significantly higher in the high-DM group than in the low-DM group: 17.4 mg/dL versus 9.2 mg/dL (P = .018).

CONCLUSIONS

It was clarified that D-MELD could predict early and long-term surgical outcomes in the recipients who were HCV-positive and who had smaller grafts.

The evolution of anterior sector venous drainage in right lobe living donor liver transplantation: does one technique fit all?

In living donor liver transplantation (LDLT), an adequate hepatic venous outflow constitutes one of the basic principles of a technically successful procedure. The issue of whether the anterior sector (AS) of the right lobe (RL) graft should or should not be routinely drained has been controversial. The aim of this 10-year, single-center, retrospective cohort study was to review the evolution of our hepatic venous outflow reconstruction technique in RL grafts and evaluate the impact of routine AS drainage strategy on the outcome. The study group consisted of 582 primary RL LDLT performed between July 2004 and December 2014. The cases were divided into 3 consecutive periods with different AS venous outflow reconstruction techniques, which included middle hepatic vein (MHV) drainage in Era 1 (n=119), a more selective AS drainage with cryopreserved homologous grafts in Era 2 (n=391), and routine segment 5 and/or 8 oriented AS drainage with synthetic grafts in Era 3 (n=72). Intraoperative portal flow measurement with routine splenic artery ligation (SAL) technique (in RL grafts with a portal flow of ≥ 250 mL/min/100 g liver tissue) was added later in Era 3. These 3 groups were compared in terms of recipient and donor demographics, surgical characteristics and short-term outcome. The rate of AS venous drainage varied from 58.8% in Era 1 and 35.0% in Era 2 to 73.6% in Era 3 (P<0.001). Perioperative mortality rate of recipients significantly decreased over the years (15.1% in Era 1 and 8.7% in Era 2 vs. 2.8% in Era 3, P=0.01). After the addition of SAL technique in the 45 cases, there was only 1 graft loss and no perioperative mortality. One-year recipient survival rate was also significantly higher in Era 3 (79.6% in Era 1 and 86.1% in Era 2 vs. 92.1% in Era 3, P=0.002). Routine AS drainage via segment 5 and/or 8 veins using synthetic grafts is a technique to fit all RL grafts in LDLT. Addition of SAL effectively prevents early graft dysfunction and significantly improves the outcome.

Early Graft Dysfunction in Living Donor Liver Transplantation and the Small for Size Syndrome

LDLT has arisen as a viable means to reduce waitlist mortality. However, its widespread embrace by the liver transplant community has been met with frustration centered on donor morbidity and small-for-size-syndrome. Focusing on the later entity, we describe the initial recognition of this early graft dysfunction, the theorized pathophysiology and solutions to remedy its emergence.

Portal flow is the main predictor of early graft dysfunction regardless of the GRWR status in living donor liver transplantation - a retrospective analysis of 134 patients

BACKGROUND

Sometimes even in adequate graft to recipient weight ratio (GRWR) settings and after ruling out all other causes, recipients still show features of the small for size syndrome. The purpose of this study was to evaluate all causative factors responsible for early graft dysfunction fulfilling the definition of the small for size syndrome, regardless of the GRWR status, and with particular emphasis on portal flow (ml/min/100 g). We also tried to establish whether a high portal flow on intraoperative Doppler study immediately after reperfusion can predict graft dysfunction.

MATERIAL AND METHODS

Early graft dysfunction was defined according to the definitions given for the small for size syndrome by the Kyushu University Group. Patients undergone living donor liver transplantations between January 2010 and December 2012 were analyzed. We routinely do Doppler ultrasound (USG) immediately after reperfusion and daily for 5 days. The portal vein flow after routine Doppler examination immediately after reperfusion was noted as the portal vein flow at day 0.

RESULTS

19 of 134 patients showed features of early graft dysfunction as defined. On univariate analysis, hepatitis C virus (HCV) and portal vein flow immediately after reperfusion were significant predictors of postoperative graft dysfunction. (p = 0.008 and p < 0.0001). On multivariate logistic regression, only portal vein flow after reperfusion (p = 0.002) remained as the significant predictor of postoperative graft dysfunction. A portal flow of greater than 190 (ml/min/100 g) was significant in predicting graft dysfunction (p < 0.0001) with an AUROC of 0.709. GRWR was not a significant predictor.

CONCLUSION

A portal vein flow immediately after reperfusion >190/ml/min/100 g. reliably predicted whether a graft would behave as small for size or not, regardless of the GRWR status. Portal vein flow was the most significant predictor of graft dysfunction.

Prediction factors of postoperative hyperbilirubinemia in living right lobe donor: a single-center analysis of 210 cases

BACKGROUND

Hyperbilirubinemia in living liver donor is very common, but the causes are still unclear.

AIMS

We sought to clarify the risk factors and predictors of nonobstructive hyperbilirubinemia among living donors.

METHODS

We divided 210 consecutive right liver lobe donors into two groups according to the peak total bilirubin postoperatively. We collected data on preoperative, intraoperative, and postoperative biochemical measurements retrospectively, performing multivariate logistic regression analysis adjusting for potential confounders of the risk of hyperbilirubinemia.

RESULTS

There were significant differences between the two groups in donor age, body mass index, operative time, blood loss, macrovescicular steatosis, allogeneic blood transfusion rate, intensive care unit stay, hospital stay and Clavien score after donation (P < .05). Age, graft/donor weight, operative time, and blood loss were significantly associated with the risk of hyperbilirubinemia upon logistic regression analysis.

CONCLUSION

Hyperbilirubinemia, one type of hepatic dysfunction after a living donor procedure, was associated with multiple independent risk factors.

Adult left liver transplantation from split livers and living donors: a 14-year single-center experience

BACKGROUND

In an era of organ scarcity, the use of left liver grafts for adult recipients could increase the access to liver transplantation (LT). The aim of this study was to evaluate the results in a single-center series of adult left LT over a 14-yr period.

PATIENTS AND METHODS

Between March 1996 and March 2010, 30 adult patients underwent LT with a left liver obtained from 16 split cadaveric livers and 14 living donors (LD). Portal vein inflow modulation was performed in selected cases.

RESULTS

A total of 19 (63.3%) grafts had early dysfunction leading to graft failure in six cases (20%). One third of the grafts developed small-for-size syndrome (SFSS). One-yr patient and graft survival was 80% and 76.7%, respectively. Regarding two successive periods, one-yr patient and graft survival dramatically increased from 62.5% to 100% (p = 0.01) and 56.2% to 100% (p = 0.002), respectively. Multivariate analysis disclosed that completion of a portosystemic shunt and the occurrence of post-operative ascites were significantly associated with graft failure.

CONCLUSIONS

Our results support that improved surgical techniques and careful patient selection can lead to a safe use of left livers for transplantation in adult recipients. Inflow modulation could be performed in very selected cases.

[Small-for-size: experimental findings for liver surgery]

The characteristics of the hepatic macrocirculation, i.e., the parallel portal-venous and arterial blood supply, is of utmost relevance for liver surgery. With extended hepatectomy or transplantation of a reduced-size liver the remaining or transplanted liver tissue is overperfused because the liver fails to regulate the portal-venous inflow. This portal hyperperfusion is responsible for the initiation of liver cell proliferation but represents at the same time one of the substantial events in the pathogenesis of the small-for-size syndrome. Portal-venous hyperperfusion, the so-called hepatic arterial buffer response, which describes the semi-reciprocal relationship between the portal-venous and hepatic arterial blood flows, leads to an arterial hypoperfusion of the small-for-size liver. In this article experimental and clinical data are discussed which underline the high but so far overseen relevance of this arterial underperfusion in the development of a small-for-size syndrome.

Clinical anatomy related to the hepatic veins for right lobe living donor liver transplantation

The complexity of liver reconstruction has limited partial right lobe living donor liver transplantation. It is largely due to the difficulty of dealing with the middle hepatic vein. We sought to define the anatomic features of hepatic veins. Forty-one fresh adult livers, 43 formalin-fixed adult cadaver livers, and 91 adult liver corrosion casts were used for the study. We determined the number of branches, the maximum diameter, the whole length, the extrahepatic length of the hepatic veins, and the deviation of the middle hepatic vein from the main portal fissure. Nakamura and Tsuzuki's classification of hepatic vein types was used. Type A, B, and C accounted for 59.4, 27.8, and 12.8% of all specimens in this study, respectively. The middle and left hepatic veins formed a common trunk in 60.3% of the specimens, and the length of the common trunk was 1.12 ± 0.62 cm. The degree of deviation to the right of the middle hepatic vein from the main portal fissure was 14.11° ± 12.65°. The frequency of hepatic vein types and the degree of deviation to the right of the middle hepatic vein in this study is markedly different from that reported in other literature. The anatomic features of the hepatic veins in this study suggest that right lobe living donor liver transplantation is more suitable for Chinese.