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Objective: To compare graft survival after living donor liver transplantation (LDLT) in patients receiving graft-to-recipient weight ratio (GRWR) <0.8 versus GRWR≥0.8 grafts and identify risk factors for graft loss using GRWR<0.8 grafts. Background: Favorable outcomes after LDLT using GRWR<0.8 grafts were recently reported; however, these results have not been validated using multicenter data. Methods: This multicentric cohort study included 3450 LDLT patients. Graft survival was compared between 1:3 propensity score–matched groups and evaluated using various Cox models in the entire population. Risk factors for graft loss with GRWR<0.8 versus GRWR≥0.8 grafts were explored within various subgroups using interaction analyses, and outcomes were stratified according to the number of risk factors. Results: In total, 368 patients (10.7%) received GRWR<0.8 grafts (GRWR<0.8 group), whereas 3082 (89.3%) received GRWR≥0.8 grafts (GRWR≥0.8 group). The 5-year graft survival rate was significantly lower with GRWR<0.8 grafts than with GRWR≥0.8 grafts (85.2% vs 90.1%, P=0.013). Adjusted hazard ratio for graft loss using GRWR<0.8 grafts in the entire population was 1.66 (95% CI: 1.17–2.35, P=0.004). Risk factors exhibiting significant interactions with GRWR<0.8 for graft survival were age ≥60 years, Model for End-stage Liver Disease score ≥15, and male donor. When ≥2 risk factors were present, GRWR<0.8 grafts showed a higher risk of graft loss compared with GRWR≥0.8 graft in LDLT (hazard ratio 2.98, 95% CI: 1.79–4.88, P<0.001). Conclusions: GRWR< 0.8 graft showed inferior graft survival than controls (85.2% vs 90.1%), especially when ≥2 risk factors for graft loss (among age 60 years or above, Model for End-stage Liver Disease score ≥15, or male donor) were present. [ABSTRACT FROM AUTHOR]

Background: Post-reperfusion syndrome (PRS) during liver allograft reperfusion is characterized by hemodynamic instability, including hypotension, bradycardia, and arrhythmias. The incidence and risk factors of PRS are primarily studied in cadaveric liver transplantation. This study aims to estimate the incidence of PRS and identify associated factors in living donor liver transplantation (LDLT). Objective: To estimate the incidence of PRS and evaluate factors associated with its development in LDLT. Methods: We prospectively observed 70 adult patients with chronic liver disease who underwent LDLT between August 2020 and March 2022. Patients were categorized into two groups: those who developed PRS (PRS group) and those who did not (non-PRS group). Results: PRS occurred in 26 of 70 recipients (37.1%). The PRS group had significantly higher mean MELD scores, lower preoperative fibrinogen levels, and longer graft cold ischemia times (p= 0.027, p= 0.015, p= 0.045, respectively). These patients also experienced greater intraoperative blood loss and required more blood product transfusions. Postoperatively, the PRS group had longer mechanical ventilation times, a prolonged vasopressor requirement, and higher peak bilirubin levels in the first 7 days (p= 0.009, p= 0.001, p= 0.002, respectively) Conclusion: PRS is associated with more severe liver disease, greater intraoperative blood loss, and higher blood product transfusions. Postoperatively, patients with PRS had longer mechanical ventilation, prolonged vasopressor use, and elevated bilirubin levels. [ABSTRACT FROM AUTHOR]

We investigated clinical information underneath the beat-to-beat fluctuation of the arterial blood pressure (ABP) waveform morphology. We proposed the Dynamical Diffusion Map algorithm (DDMap) to quantify the variability of morphology. The underlying physiology could be the compensatory mechanisms involving complex interactions between various physiological mechanisms to regulate the cardiovascular system. As a liver transplant surgery contains distinct periods, we investigated its clinical behavior in different surgical steps. Our study used DDmap algorithm, based on unsupervised manifold learning, to obtain a quantitative index for the beat-to-beat variability of morphology. We examined the correlation between the variability of ABP morphology and disease acuity as indicated by Model for End-Stage Liver Disease (MELD) scores, the postoperative laboratory data, and 4 early allograft failure (EAF) scores. Among the 85 enrolled patients, the variability of morphology obtained during the presurgical phase was best correlated with MELD-Na scores. The neohepatic phase variability of morphology was associated with EAF scores as well as postoperative bilirubin levels, international normalized ratio, aspartate aminotransferase levels, and platelet count. Furthermore, variability of morphology presents more associations with the above clinical conditions than the common BP measures and their BP variability indices. The variability of morphology obtained during the presurgical phase is indicative of patient acuity, whereas those during the neohepatic phase are indicative of short-term surgical outcomes. [ABSTRACT FROM AUTHOR]

Aim. To analyse the surgical aspects of performing a split liver transplantation in patients with end-stage liver disease.Key findings. Split liver transplantation (SLT) is a technique allowing two functional grafts to be obtained from one deceased donor to simultaneously save the lives of two recipients. The global clinical experience of SLT application currently comprises more than three decades. Criteria necessary for successful SLT were developed, based both on assessment of graft quality (age and anthropometric characteristics of the donor, laboratory parameters, ultrasound data, length of stay in intensive care, as well as macroscopic intraoperative assessment of the liver), and on the selection of recipients (primarily in accordance with the height-weight characteristics and the use of the GRWR [graftto-recipient weight ratio]). The use of these criteria allows the results to be achieved comparable to other types of liver transplantation (a whole liver from a deceased donor or liver fragments of an intravital donor). However, issues involved with of the optimal choice of surgical techniques remain to be solved, which include such key aspects as the anatomical method of separation (left lateral section and extended right lobe; anatomical left and right lobes of the liver), an optimal method of separation (ex situ or in situ) and others. The issues of logistics of the SLT application, including the principles of allocation of transplants, also remain significant. Ethical aspects are equally important, since, theoretically, the widespread introduction of the SLT technique may increase the risk of graft loss. The immediate and long-term SLT results require further study, which makes it possible to form a more objective opinion on the effectiveness of the technique.Conclusion. SLT shows good results both in the near and in the remote period. The key aspects of SLT performing are a deep understanding of the variant anatomy of the liver and a high level of knowledge of liver resection surgery. The active use of SLT allows the pool of donor organs to be increased, which is of great importance under the conditions of their permanent lack.

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

Multicollinearity represents a high degree of linear intercorrelation between explanatory variables in a multiple regression model and leads to incorrect results of regression analyses. Diagnostic tools of multicollinearity include the variance inflation factor (VIF), condition index and condition number, and variance decomposition proportion (VDP). The multicollinearity can be expressed by the coefficient of determination (Rh 2) of a multiple regression model with one explanatory variable (Xh) as the model's response variable and the others (Xi [i ≠ h]) as its explanatory variables. The variance (σh²) of the regression coefficients constituting the final regression model are proportional to the VIF (1-1-Rh²). Hence, an increase in Rh² (strong multicollinearity) increases σh². The larger σh² produces unreliable probability values and confidence intervals of the regression coefficients. The square root of the ratio of the maximum eigenvalue to each eigenvalue from the correlation matrix of standardized explanatory variables is referred to as the condition index. The condition number is the maximum condition index. Multicollinearity is present when the VIF is higher than 5 to 10 or the condition indices are higher than 10 to 30. However, they cannot indicate multicollinear explanatory variables. VDPs obtained from the eigenvectors can identify the multicollinear variables by showing the extent of the inflation of σh 2 according to each condition index. When two or more VDPs, which correspond to a common condition index higher than 10 to 30, are higher than 0.8 to 0.9, their associated explanatory variables are multicollinear. Excluding multicollinear explanatory variables leads to statistically stable multiple regression models. [ABSTRACT FROM AUTHOR]

Background: The prognosis of the patients of acute liver failure (ALF) with onset of hepatic coma is often dismal. ALF is a well-accepted indication for liver transplantation (LT) and has markedly improved the prognosis of these patients. However, its role in ALF patients with onset of hepatic coma has never been elucidated before. The aim of our study was to analyze the outcome in patients of ALF with hepatic coma who underwent LT. Material/Methods: From January 2002 to December 2015, a total of 726 liver transplantations were done at China Medical University Hospital, Taiwan. The hospital database of 59 recipients that underwent LT for ALF was analyzed. Eleven ALF patients with the onset of hepatic coma (grade IV encephalopathy) requiring mechanical ventilatory support were retrospectively analyzed. The patients were sub-grouped in 2 groups depending on the timing of LT after the onset of hepatic coma: Group A had LT within 48 h of onset of coma (n=7) and Group B had LT after 48 h of onset of coma (n=4). Results: The study cohort (group A and B) comprised 8 males and 3 females, with an average age of 39.63±13.95 years (range, 13 to 63). Ten patients received living donor liver transplantation (LDLT) and deceased donor liver transplantation (DDLT) was done in 1 recipient. All the patients in group A had complete neurological recovery and were extubated within 48 h after LT, whereas extubation was delayed for various reasons for group B patients. At a mean follow up of 36 months (range, 20 to 76 months), the overall survival of all the recipients (group A and B) was 72%. Three-year survival for Group A (n=7) was 85% and for Group B (n=4) it was 50%. There were no acute rejection episodes. Conclusions: LT is an acceptable modality of treatment for patients of ALF with new onset of hepatic coma. Neurological recovery is expected in all patients if LT can be done within 48 h of onset of hepatic coma without increasing the risk of morbidity. Due to shortage of deceased donor organs in Asia, LDLT can be used proactively, with a success rate comparable to that of non-ALF patients undergoing LT. [ABSTRACT FROM AUTHOR]

Urahashi T, Mizuta K, Sanada Y, Wakiya T, Yasuda Y, Kawarasaki H. Liver graft volumetric changes after living donor liver transplantation with segment 2 graft for small infants. Abstract: LT for small infants weighing <5 kg with liver failure might require innovative techniques for size reduction and transplantation of small grafts to avoid large-for-size graft, but little is known about post-transplant graft volumetric changes. Five of 172 children who underwent LDLT received monosegment or reduced monosegment grafts using a modified Couinaud's segment II (S2) graft for LDLT. Serial CT was used to evaluate the changes in the GV and other factors before LDLT and one and three months after LDLT. The shape of these grafts was classified into an OL type and an LL type. The GV increased in all patients one month after LDLT, whereas the GV decreased three months after LDLT in OL in comparison with one month after LDLT. The GRWR of the OL type has tended to decrease at three months, whereas the LL type showed a continuous increase with time, but finally they had adapted graft size for their body size. In conclusion, the volume of S2 grafts after LDLT had unique changes toward the ideal volume for the child weight when they received the appropriate liver volume. [ABSTRACT FROM AUTHOR]

To improve the processes used for perfusion of the explanted graft and measuring the portal venous pressure ( PVP) in adult living donor transplantation ( LDLT), we performed transumbilical portal venous catheterization ( TPVC) to reopen the umbilical vein and insert the catheter for seven adult patients undergoing left lobe LDLT. There were no major complications as a result of this procedure. This procedure prior to implanting the graft was derived from our experience and is a classic diagnostic technique used during liver surgery. It is a simple and effective procedure for perfusion and washout of the graft and for the safe monitoring of the intraoperative PVP. We hope that this technique for left lobe LDLT will be helpful to others using postoperative PVP monitoring, administration of therapeutic drugs through the portal vein, and temporal portal decompression by preparation of extracorporeal shunting in patients with a small-for-size graft. [ABSTRACT FROM AUTHOR]

Shigeta T, Sakamoto S, Kanazawa H, Fukuda A, Kakiuchi T, Karaki C, Uchida H, Matsuno N, Tanaka H, Kasahara M. Diaphragmatic hernia in infants following living donor liver transplantation: Report of three cases and a review of the literature. Abstract: DH is a rare complication following LT. This report presents three cases of right-sided DH after LT using a left-sided graft. All of the patients were younger than one yr of age, and they were critically ill owing to their original disease, characterized by biliary atresia, progressive familiar intrahepatic cholestasis, and acute liver failure. DH occurred with sudden onset within three months after LT. All of the cases were promptly diagnosed and treated. A literature review of 24 cases of DH identified four factors associated with DH: left-sided graft, right-sided DH, relatively delayed onset of DH, and age-specific chief complaint. DH following LT should be considered as a potential surgical complication when a left-sided graft is used, especially in small infants with coagulopathy and malnutrition. [ABSTRACT FROM AUTHOR]

BACKGROUND: We undertook a retrospective assessment of risk factors for biliary stricture after adult living donor liver transplantation (LDLT) and evaluated risk reduction following the implementation of modified surgical procedures. METHODS: Between June 1997 and December 2009, 85 adult patients underwent LDLT. Up to September 2006, we performed duct-to-duct hepaticocholedochostomy (D-D) in 38 patients and Roux-en-Y hepaticojejunostomy (R-Y) in 24 patients. Risk factors for biliary stricture were analyzed for these patients. We then performed D-D in 23 patients using modified procedures and assessed the resultant outcomes. RESULTS: D-D was a significant risk factor in the 62 patients who underwent LDLT before September 2006. Despite this result, we decided to employ only D-D for subsequent cases. Since the presence of multiple graft bile duct orifices was a significant risk factor in the 38 patients who underwent D-D, we used modified procedures after October 2006 to address grafts with multiple bile duct orifices. The procedures included: 1) inserting a biliary tube from the common bile duct; 2) placing the tip of tube beyond the anastomosis; 3) inserting the tubes in all the anastomoses if multiple; and 4) maintaining the tube for 6 months postoperatively. The incidence of biliary stricture after D-D was significantly less frequent with the use of these procedures (before: 36%; after: 13%). CONCLUSIONS: In our early experience, D-D was a significant risk factor for biliary stricture after adult LDLT. Although we are now employing only D-D, our procedural modifications seem promising for preventing biliary stricture after D-D. [ABSTRACT FROM AUTHOR]