Adult right living-donor liver transplantation with special reference to reconstruction of the middle hepatic vein

Vascular outflow reconstruction in right lobe living donor liver transplantation with and without middle hepatic vein

Although living donor liver transplantation has evolved, small-for-size syndrome remains a feared complication. Achieving optimal outflow for the graft with limited donor risk is possible with an experienced team and different techniques. Here we describe the technical aspects of living donor liver transplantation using a right lobe graft, including the different types of grafts, venous reconstructions and the importance of preoperative workup.

Metallic Stents for Hepatic Venous Outflow Obstruction After Living-Donor Liver Transplantation and their Therapeutic Effects

BACKGROUND

Living-donor liver transplantation (LDLT) is established as a standard therapy for end-stage liver disease; however, vessel reconstruction is more demanding due to the short length and small size of the available structures compared with deceased-donor whole liver transplantation. Interventional radiology (IR) has become the first-line treatment for vascular complications after LDLT. Hepatic venous outflow obstruction (HVOO) is a life-threatening complication after LDLT. The aim of this study of 592 adult-to-adult LDLT cases was to investigate the safety and efficacy of stent implantation for HVOO after LDLT.

METHODS

Records of patients who developed HVOO requiring any treatment were collected with special reference to the metallic stent implantation. There were 232 left-side grafts and 360 right-side grafts. Sixteen cases developed HVOO after LDLT with an incidence rate of 2.7%, 5 with a left liver graft (2%), and 11 with a right-side graft (3%). The IR was attempted for 14 cases; among those, 8 cases were treated by stent implantation.

RESULTS

The technical success rate of the initial stent implantation was 100%. The pressure gradient at the stenotic site significantly improved from 12.2 (range, 10.9-20.4 cm H2O) to 3.9 cm H2O (range, 1.4-8.2 cm H2O; P = .03). The volume of the congested graft liver decreased significantly from 1448 (range, 788-2170 mL) to 1265 mL (range, 748-1665 mL; P = .01), and the serum albumin level improved significantly from 3.3 (range, 1.7-3.7 g/dL) to 3.7 g/dL (range, 2.9-4.1 g/dL; P = .02). No procedure-related complication was noted, and the long-term stent patency was 100%.

CONCLUSION

Metallic stent implantation for stenotic venous anastomosis after LDLT is a safe and effective treatment.

Importance of reconstruction of middle hepatic vein tributaries of right-lobe grafts in living donor liver transplantation: demonstration of the reconstruction technique

PURPOSE

The aim of the present study on living donor liver transplantation (LDLT) using a right-lobe graft without the middle hepatic vein (MHV) was to investigate the clinical impact of MHV tributary reconstruction using our criteria and techniques.

METHODS

The medical records of 40 patients who underwent adult LDLT using a right-lobe graft without the MHV between April 2008 and December 2020 were retrospectively reviewed. In this cohort, the criterion for MHV tributary reconstruction was estimated drainage volume of each MHV tributary greater than 100 mL. The drainage vein of segment 8 (V8) was reconstructed as the common orifice of the right hepatic vein and V8 using a venous patch graft, and that of segment 5 was reconstructed using artificial vascular grafts. The outcomes were compared between the groups with and without MHV tributary reconstruction. Factors associated with postoperative massive ascites were also investigated.

RESULTS

Twenty patients underwent MHV tributary reconstruction. There were no significant differences in the amount of postoperative ascites, Clavien-Dindo classification ≥ III postoperative complications, and 90-day in-hospital mortality between the groups (P = 0.678, P = 1.000, and P = 0.244, respectively). On multivariate analyses, a low-estimated functional graft-to-recipient weight ratio, which was calculated using estimated graft volume minus the territory of MHV tributaries that was not reconstructed, was identified as an independent predictor of postoperative massive ascites (odds ratio, 40.479; 95% confidence interval, 3.823-428.622).

CONCLUSION

The present study suggests that selective MHV tributary reconstruction might be useful for achieving successful graft function.

Single Orifice Outflow Reconstruction: Refining the Venous Outflow in Modified Right Lobe Live Donor Liver Transplantation

BACKGROUND

MHV reconstruction is essential to avoid anterior sector congestion in adult live donor liver transplantation (LDLT) using a modified right lobe graft.

AIMS

The objective of this study is to evaluate the graft and patient outcomes with single orifice outflow reconstruction technique (SORT) (RHV + neo-MHV combined reconstruction on IVC) vs. dual outflow reconstruction technique (DORT) (RHV and neo-MHV separately reconstructed on IVC) in a modified right lobe LDLT.

METHODS

Prospectively collected data of consecutive patients undergoing LDLT from June 2011 to August 2018 were analyzed. The patients were divided into two groups: SORT (n = 207) and DORT (n = 108). The perioperative morbidity and mortality were compared between two groups.

RESULTS

The two groups were comparable in baseline preoperative characteristics. Intraoperatively, warm ischemia time (27 vs. 45 min, p < 0.001), anhepatic phase (132 vs. 159 min, p < 0.001), and operative time (680 vs. 840 min, p < 0.001) were significantly shorter in SORT group. SORT group also had significantly lower GRWR (0.92 vs. 1.06, p < 0.001) and higher portal flow (2.4 vs. 2.7 L/min, p = 0.02). Postoperatively, SORT group had lower peak AST (177 vs. 209 IU/L, p < 0.001), ALT (163 vs. 189 IU/L, p = 0.004), creatinine levels (0.98 vs. 1.10, p = 0.01), rate of severe sepsis (13.7% vs. 22.9%, p = 0.03), major morbidity (50.7% vs. 62.6%, p = 0.03), shorter ICU (9 vs. 14 days, p < 0.001), and hospital stay (21 vs. 26 days, p = 0.03). Overall survival rates were comparable.

CONCLUSION

A SORT leads to improved early graft function and perioperative morbidity in modified right lobe LDLT in spite of having lower GRWR and higher portal flow.

Intraoperative Increase of Portal Venous Pressure is an Immediate Predictor of Posthepatectomy Liver Failure After Major Hepatectomy: A Prospective Study

OBJECTIVES

The aim of this study was to assess intraoperative changes of hepatic macrohemodynamics and their association with ascites and posthepatectomy liver failure (PHLF) after major hepatectomy.

SUMMARY OF BACKGROUND DATA

Large-scale ascites and PHLF remain clinical challenges after major hepatectomy. No study has concomitantly evaluated arterial and venous liver macrohemodynamics in patients undergoing liver resection.

METHODS

Portal venous pressure (PVP), portal venous flow (PVF), and hepatic arterial flow (HAF) were measured intraoperatively pre- and postresection in 67 consecutive patients with major hepatectomy (ie, resection of ≥3 liver segments). A group of 30 patients with minor hepatectomy served as controls. Liver macrohemodynamics and their intraoperative changes (ie, Δ) were analyzed as predictive biomarkers of ascites and PHLF using Fisher exact, t test, or Wilcoxon rank sum test for univariate and logistic regression for multivariate analyses.

RESULTS

Major hepatectomy increased PVP by 26.9% (P = 0.001), markedly decreased HAF by 40.7% (P < 0.001), and slightly decreased PVF by 13.4% (P = 0.011). Minor resections had little effects on hepatic macrohemodynamics. There was no significant association of liver macrohemodynamics with ascites. While middle hepatic vein resection caused higher postresection PVP after right hepatectomy (P = 0.04), the Pringle maneuver was associated with a significant PVF (P = 0.03) and HAF reduction (P = 0.03). Uni- and multivariate analysis revealed an intraoperative PVP increase as an independent predictor of PHLF (P = 0.025).

CONCLUSION

Intraoperative PVP kinetics serve as independent predictive biomarker of PHLF after major hepatectomy. These data highlight the importance to assess intraoperative dynamics rather than the pre- and postresection PVP values.

Venous outflow reconstruction using a polytetrafluoroethylene (PTFE) graft in right lobe living donor liver transplantation: A single center study

BACKGROUND

Venous outflow reconstruction is very important especially in right lobe living donor liver transplantation without middle hepatic vein. Various interposition (venous or synthetic) grafts have been recommended for reconstruction of anterior sector tributaries.

METHODS

We aimed to describe our surgical technique and analyze anterior sector venous reconstruction using expanded polytetrafluroethylene graft. Retrospective analysis of prospectively collected data for 760 primary right lobe living donor liver transplantations performed at our institute between December 2011 and June 2018. Reconstruction of anterior sector: expanded polytetrafluroethylene (group A, n = 705) and autologous vein (group B, n = 55).

RESULTS

Pretransplant characteristics were comparable among both groups. Group A has significantly lower cold ischemia time (68.7 ± .3.5 minutes vs 127.8 ± 7.2 minutes; P < .001) and anhepatic time (116.3 ± 5.5 minutes vs 190.81 ± 9.35 minutes; P < .001) compared with group B. There was no difference in recovery pattern of liver functions, morbidity, and mortality between the 2 groups. One- and 6-month patency rates of interposition grafts were 97.6% and 84.4% (group A) and 96.4% and 78.1% (group B), respectively.

CONCLUSION

In centers with limited access to homologous or autologous vascular grafts, use of expanded polytetrafluroethylene graft for anterior sector venous outflow reconstruction in right lobe living donor liver transplantation is a viable option with excellent patency and patient outcomes.

Clinical Significance of Spontaneous Portosystemic Shunts in Living Donor Liver Transplantation

Spontaneous portosystemic shunts (SPSS) are commonly observed in patients undergoing living donor liver transplantation (LDLT); however, their impact on the outcome after transplantation is unclear. We aimed to assess the type, size, and the effects of SPSS on outcomes after LDLT. A total of 339 LDLT recipients in a single institution were included. The type and diameter of the SPSS (splenorenal shunt [SRS], oesogastric shunt, and umbilical shunt) were retrospectively analyzed. A large shunt was defined as having a diameter ≤7 mm. No portal flow modulation was attempted over time. Portal complications were defined as stenosis, thrombosis, or hepatofugal flow requiring any treatment after transplantation. There were 202 (59.0%) patients who exhibited at least 1 large SPSS. Neither the size nor type of SPSS was associated with mortality, morbidity, or liver function recovery. However, the incidence of portal complications was significantly higher in patients with a large SRS (8.6% versus 2.9%; P = 0.04). Multivariate analysis of portal complications revealed 2 independent predictors: pre-LT portal vein thrombosis (PVT) and SRS size. The observed risk among recipients with pre-LT PVT was 8.3% when the SRS was ≤7 mm, but increased to 38.5% when the SRS was >15 mm. The present study suggests that large SPSS do not negatively affect the outcomes after LDLT. However, a large SRS is associated with a higher risk of portal complications, particularly in recipients with pre-LT PVT, for whom intraoperative intervention for SRS should be considered. Otherwise, a conservative approach to SPSS during LDLT seems reasonable.

Simulation and navigation liver surgery: an update after 2,000 virtual hepatectomies

The advent of preoperative 3-dimensional (3D) simulation software has made a variety of unprecedented surgical simulations possible. Since 2004, we have performed more than 2,000 preoperative simulations in the University of Tokyo Hospital, and they have enabled us to obtain a great deal of information, such as the detailed shape of liver segments, the precise volume of each segment, and the volume of hepatic venous drainage areas. As a result, we have been able to perform more aggressive and complicated surgery safely. The next step is to create a navigation system that will accurately reproduce the preoperative plan. Real-time virtual sonography (RVS) is a navigation system that provides fusion images of ultrasonography and reconstructed computed tomography images or magnetic resonance images. The RVS system facilitates the surgeon's understanding of interpretation of ultrasound images and the detection of tumors that are difficult to find by ultrasound alone. In the near future, surgical navigation systems may evolve to the point where they will be able to inform surgeons intraoperatively in real time about not only intrahepatic structures, such as vessels and tumors, but also the portal territory, hepatic vein drainage areas, and resection lines that have been planned preoperatively.

Increased Surgical Complications but Improved Overall Survival with Adult Living Donor Compared to Deceased Donor Liver Transplantation: A Systematic Review and Meta-Analysis

Background

Living donor liver transplantation (LDLT) provides an alternative to deceased donor liver transplantation (DDLT) for patients with end-stage liver disease in the circumstance of scarcity of deceased grafts. However, the outcomes of LDLT remain controversial.

Method

A systematic review and meta-analysis were performed to compare the outcomes of LDLT with DDLT. Twelve outcomes were assessed.

Results

Thirty-nine studies involving 38563 patients were included. LDLT was comparable in red blood cell transfusion, perioperative mortality, length of hospital stay, retransplantation rate, hepatitis C virus recurrence rate, and hepatocellular carcinoma recurrence rate with DDLT. Cold ischemia time was shorter and duration of recipient operation was longer in LDLT. Postoperative intra-abdominal bleeding rate occurred less frequently in LDLT recipients (odds ratio (OR) = 0.64, 95%confidence interval (CI) = 0.46 − 0.88, P = 0.006), but this did not decrease the perioperative mortality. LDLT was associated with significantly higher biliary (OR = 2.23, 95%CI = 1.59 − 3.13, P < 0.00001) and vascular (OR = 2.00, 95%CI = 1.31 − 3.07, P = 0.001) complication rates and better overall survival (OS) (1 year: OR = 1.32, 95%CI = 1.01 − 1.72, P = 0.04; 3 years: OR = 1.39, 95%CI = 1.14 − 1.69, P = 0.0010; and 5 years: OR = 1.33, 95%CI = 1.04 − 1.70, P = 0.02). According to subgroup analysis, biliary complication rate and OS improved dramatically as experience increased, while vascular complication rate could not be improved because it was mainly caused by the difference of the donor type itself.

Conclusions

LDLT remains a valuable option for patients in need of liver transplantation for it provides an excellent alternative to DDLT without compromising recipient outcomes. Further refinement in biliary and vascular reconstruction techniques and the accumulation of liver transplantation centers' experience are the key factors in expanding the application of LDLT.

Small-for-size syndrome in liver transplantation: Definition, pathophysiology and management

BACKGROUND

Since the first success in an adult patient, living donor liver transplantation (LDLT) has become an universally used procedure. Small-for-size syndrome (SFSS) is a well-known complication after partial LT, especially in cases of adult-to-adult LDLT. The definition of SFSS slightly varies among transplant physicians. The use of a partial liver graft has risks of SFSS development. Persistent portal vein (PV) hypertension and PV hyper-perfusion after LT were identified as the main factors. Hence, various approaches were explored to modulate PV flow and decrease PV pressure in order to alleviate this syndrome. Herein, the definition, clinical symptoms, pathophysiology, basic research, as well as preventive and treatment strategies for SFSS are reviewed based on an extensive review of the literature and on our own experiences.

DATA SOURCES

The articles were collected through PubMed using search terms "liver transplantation", "living donor liver transplantation", "living liver donation", "partial graft", "small-for-size graft", "small-for-size syndrome", "graft volume", "remnant liver", "standard liver volume", "graft to recipient body weight ratio", "sarcopenia", "porcine", "swine", and "rat". English publications published before March 31, 2020 were included in this review.

RESULTS

Many transplant surgeons performed PV flow modulation, including portocaval shunt, splenic artery ligation and splenectomy. With these techniques, patient outcome has been improved even when using a "small" graft. Other factors, such as preoperative recipients' nutritional and skeletal muscle status, graft congestion, and donor factors, were also identified as risk factors which all have been addressed using various strategies.

CONCLUSIONS

The surgical approach controlling PV flow and pressure could help to prevent SFSS especially in severely ill recipients. In the absence of efficacious medications to resolve SFSS, conservative treatments, including aggressive fluid balance correction for massive ascites, anti-microbiological therapy to prevent or control sepsis and intensive nutritional therapy, are all required if SFSS could not be prevented.

Sex differences in postsurgical skeletal muscle depletion after donation of living-donor liver transplantation, although minimal, should not be ignored

Background

Donor safety is the top priority in living-donor liver transplantation. Splenic hypertrophy and platelet count decrease after donor surgery are reported to correlate with the extent of hepatectomy, but other aftereffects of donor surgeries are unclear. In this study, we evaluated the surgical effects of donor hepatectomy on skeletal muscle depletion and their potential sex differences.

Methods

Among a total of 450 consecutive donor hepatectomies performed from April 2001 through March 2017, 277 donors who completed both preoperative and postoperative (60–119 days postsurgery) evaluation by computed tomography were the subjects of this study. Donors aged 45 years or older were considered elderly donors. Postoperative skeletal muscle depletion was assessed on the basis of the cross-sectional area of the psoas major muscle. Postoperative changes in the spleen volume and platelet count ratios were also analysed to evaluate the effects of major hepatectomy.

Results

The decrease in the postoperative skeletal muscle mass in the overall donor population was slight (99.4 ± 6.3%). Of the 277 donors, 59 (21.3%) exhibited skeletal muscle depletion (i.e., < 95% of the preoperative value). Multivariate analysis revealed that elderly donor (OR:2.30, 95% C.I.: 1.27–4.24) and female donor (OR: 1.94, 95% C.I. 1.04–3.59) were independent risk factors for postoperative skeletal muscle depletion. Stratification of the subjects into four groups by age and sex revealed that the elderly female donor group had significantly less skeletal muscle mass postoperatively compared with the preoperative values (95.6 ± 6.8%), while the other three groups showed no significant decrease. Due to their smaller physical characteristics, right liver donation was significantly more prevalent in the female groups than in the male groups (112/144, 77.8% vs 65/133, 48.9%; p < 0.001). The estimated liver resection rate correlated significantly with the splenic hypertrophy ratio (r = 0.528, p < 0.001) and the extent of the platelet count decrease (r = − 0.314, p < 0.001), but donor age and sex did not affect these parameters.

Conclusion

Elderly female donors have a higher risk of postoperative skeletal muscle depletion. Additionally, female donors are more likely to donate a right liver graft, whose potential subclinical risks include postoperative splenic enlargement and a platelet count decrease.

Is there any correlation between liver graft regeneration and recipient's pretransplant skeletal muscle mass?-a study in extended left lobe graft living-donor liver transplantation

BACKGROUND

The end-stage liver disease causes a metabolic dysfunction whose most prominent clinical feature is the loss of skeletal muscle mass (SMM). In living-donor liver transplantation (LDLT), liver graft regeneration (GR) represents a crucial process to normalize the portal hypertension and to meet the metabolic demand of the recipient. Limited data are available on the correlation between pre-LDLT low SMM and GR.

METHODS

Retrospective study on a cohort of 106 LDLT patients receiving an extended left liver lobe graft. The skeletal muscle index (SMI) at L3 level was used for muscle mass measurement, and the recommended cut-off values of the Japanese Society of Hepatology guidelines were used as criteria for defining low muscularity. GR was evaluated as rate of volume increase at 1 month post-LT [graft regeneration rate (GRR)].

RESULTS

The median GRR at 1 month post-LT was 91% (IQR, 65-128%) and a significant correlation with graft volume-to-recipient standard liver volume ratio (GV/SLV) (rho -0.467, P<0.001), graft-to-recipient weight ratio (GRWR) (rho -0.414, P<0.001), donor age (rho -0.306, P=0.001), 1 month post-LT cholinesterase serum levels (rho 0.397, P=0.002) and pre-LT low muscularity [absent vs. present GRR 97.5% (73.1-130%) vs. 83.5% (45.2-110.9%), P=0.041] was noted. Moreover in male recipients, but not in women, it was shown a direct correlation with pre-LT SMI (rho 0.352, P=0.020) and inverse correlation with 1 month post-LT SMI variation (rho -0.301, P=0.049). A low GRR was identified as an independent prognostic factor for recipient overall survival (HR 6.045, P<0.001).

CONCLUSIONS

Additionally to the hemodynamic factors of portal circulation and the quality of the graft, the metabolic status of the recipients has a significant role in the GR process. A pre-LT low SMM is associated with impaired GRR and this negative impact is more evident in male recipients.

How Has Virtual Hepatectomy Changed the Practice of Liver Surgery?: Experience of 1194 Virtual Hepatectomy Before Liver Resection and Living Donor Liver Transplantation

OBJECTIVE

To assess how virtual hepatectomy (VH), conducted using surgical planning software, influences the outcomes of liver surgery.

BACKGROUND

Imaging technology visualizes the territories of the liver vessels, which were previously impossible. However, the clinical impact of VH has not been evaluated.

METHODS

From 2004 to 2013, we performed 1194 VHs preoperatively. Outcomes of living donor liver transplantation (LDLT) and hepatectomy for hepatocellular carcinoma (HCC)/colorectal liver metastases (CRLM) were compared between patients in whom VH was performed (VH) and those without VH evaluation (non-VH).

RESULTS

In LDLT, the rate of right liver graft use was higher in the VH (62.1%) than in the non-VH (46.5%) (P < 0.01), which did not increase morbidity of donor surgery. Duration of recipient surgery in the VH in which middle hepatic vein branch reconstruction was skipped was shorter than that in the VH with venous reconstruction. Among HCC patients with impaired liver function, portal territory-oriented resection was conducted more often in the VH than in the non-VH. The 5-year disease-free survival rate for localized HCC was higher in the VH than in the non-VH (37.2% vs 23.9%; P = 0.04). In CRLM, long-term outcomes were similar in the VH and non-VH despite the larger tumor load in the VH.

CONCLUSIONS

VH in LDLT allows double equipoise for the recipient and donor by optimizing decision-making on graft selection and venous reconstruction. VH offers a chance for radical hepatectomy even in HCC patients with impaired liver function and CRLM patients with advanced tumors, without compromising survival.

Relationship Between Venous Drainage Patterns and Regeneration of Segments 5 and 8 in Right Lobe Grafts in Adult Living-Donor Liver Transplant Recipients

OBJECTIVES

Hepatic venous congestion is associated with impaired graft regeneration in living-donor liver transplant, and the management of middle hepatic vein tributaries in the right lobe graft represents an unresolved issue. In this study, we aimed to investigate the precise outflow pattern of segments 5 and 8 between the right hepatic vein and middle hepatic vein and the respective regeneration rates after living-donor liver transplant with right lobe graft, as available data on these relevant topics are scarce.

MATERIALS AND METHODS

We conducted a retrospective analysis of computed tomography scans with 3-dimensional simulation, vessel reconstruction, and volume measurement of 38 right lobe grafts without middle hepatic vein. Follow-up time was 3 months after living-donor liver transplant.

RESULTS

In donors, segments 5 and 8 measured 141.9 ± 48.8 mL (21.0% of graft volume) and 230.4 ± 52.5 mL (34.3% of graft volume), respectively, with significant difference between volumes (P < .01). Percentage of segmental venous drainage in segment 5 was 55.5 ± 17.2% for the middle hepatic vein and 41.0 ± 20.9% for the right hepatic vein; drainage in segment 8 was 46.4 ± 13.2% for the middle hepatic vein and 52.9 ± 13.2% for the right hepatic vein. The outflow pattern was significantly different between segments for both veins (P = .01 for middle hepatic vein and P < .01 for right hepatic vein), showing that segment 5 was statistically more dependent on the middle hepatic vein and segment 8 was more dependent on the right hepatic vein. For living-donor liver transplant recipients, the prevalence of middle hepatic vein tributary reconstruction was 39.5%. At 3-month follow-up, the regeneration rate for the posterior sector was 85.8 ± 39.9%, whereas rates for segments 5 and 8 were 33.4 ± 39.7% and 68.4 ± 41.0%, respectively (P < .01).

CONCLUSIONS

In living-donor liver transplant with right lobe graft and without middle hepatic vein, segment 5 is the most vulnerable graft area for impaired regeneration. Segments 5 and 8 should be evaluated independently on the basis of their respective outflow patterns to more precisely plan the outflow management and patient outcomes.

Explant portal vein for reconstructing middle hepatic vein in right lobe living donor liver transplantation-outcome analysis

BACKGROUND

The aim of the study was to study the four week patency rates of the reconstructed neo middle hepatic vein specifically using the explant portal vein (PV) in right hemiliver live donor liver transplantation (LDLT). We hypothesized that short term patency of the neo-MHV should result in good graft and patient outcomes.

METHODS

Pre, intra and post operative variables were prospectively collected for 88 consecutive patients undergoing right hemiliver LDLT from January 2014 to October 2015.

RESULTS

Explant PV was used to reconstruct neo-MHV in 76 (86.4%, 76/88) patients. Neo MHV patency rate at 28 days with explant PV was 89.4% (59/66) and with other conduit (PTFE) was 90.9% (10/11). All occlusions were detected after 7 days. There was no impact of the patency of the neo-MHV on the incidence of early allograft dysfunction, sepsis, rejection, morbidity or mortality, despite the contribution of the anterior sector to the graft volume being more than 50% in close to two-thirds of patients.

CONCLUSION

The reconstructed neo-MHV has excellent short term patency rates at 4 weeks. Perhaps due to the absence of early occlusions, there was no impact on graft or patient outcomes in the study population.

Effect of Middle Hepatic Vein Tributaries Preserving Technique Until Just Before Graft Retrieval on Donors' Surgical Outcomes in Living Donor Liver Transplantation

BACKGROUND

The technique of preserving the major tributaries of the middle hepatic vein (MHV) (V5 and V8) until just before graft retrieval is beneficial to minimize congestion time of the graft. However, it remains unclear whether this technique exerts a burden on donors in terms of operative time, blood loss, and postoperative hepatic dysfunction. In this study we investigated adverse effects of the MHV tributaries preserving technique until immediately before graft retrieval on donors' surgical outcomes.

METHODS

Data from 71 donors who underwent right hepatectomy without MHV for a liver transplantation at our hospital from January 2002 to August 2016 were retrospectively reviewed. Donors were divided into 3 groups as follows: group 1 (n = 12), no MHV tributary reconstruction; group 2 (n = 33), single MHV tributary reconstruction; group 3 (n = 26), 2 or 3 MHV tributaries reconstruction. Donor operation time, blood loss, proportion of the remnant liver, maximum postoperative total bilirubin, aspartate aminotransferase, alanine transaminase, minimum platelets, prothrombin time, albumin level, number of days in hospital from surgery to discharge, and surgical complications were compared.

RESULTS

Compared with groups 2 and 3, group 1 exhibited shorter average operational time and less average blood loss, but the difference was not significant. Comparisons of all other factors indicated no significant differences.

CONCLUSION

The technique of preserving the major tributaries of the MHV until just immediately before graft retrieval does not appear to impose an apparent burden on donors.

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

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

Safety and efficacy of venous reconstruction in liver resection using cryopreserved homologous veins

BACKGROUND

Only a few studies have reported the resection and reconstruction of major hepatic veins during hepatectomy. Here, we present our strategy and techniques for venous reconstruction with cryopreserved homologous veins, and describe the surgical outcome.

METHODS

Among 2,387 hepatectomy patients, 39 patients who required hepatic venous reconstruction were reviewed retrospectively. Venous reconstruction was performed to secure a non-congested liver remnant volume of at least 40% of the total liver volume.

RESULTS

There was no operative mortality, and the severe morbidity rate was 5% in this series. A total of 41 veins were reconstructed; 30 with homologous veins (73.2%) and 11 with autologous veins (26.8%), with the middle hepatic vein being the most frequent (n = 23, 56%). Interposition grafting was performed more often (P = 0.003), the length of the venous resection was longer (P = 0.007), and pathologic wall infiltration of the vein was revealed more often (P = 0.002) in the homologous graft group than in the autologous graft group. The 1-, 2-, and 3-year overall patency of the reconstructed veins was 55.4%, 46.3%, and 46.3%, respectively.

CONCLUSIONS

Aggressive venous reconstruction during hepatectomy using cryopreserved homologous veins is a feasible option with satisfactory short-term outcomes, and may be warranted to improve operative safety.

Low Platelet Counts and Prolonged Prothrombin Time Early After Operation Predict the 90 Days Morbidity and Mortality in Living-donor Liver Transplantation

OBJECTIVE

The aim of the study was to investigate the association between platelet count/prothrombin time early after transplant and short-term outcomes among living-donor liver transplant (LDLT) recipients.

BACKGROUND

Postoperative platelet count and prothrombin time-international normalized ratio (PT-INR) were critical biomarkers in LDLT.

METHODS

The study participants consisted of 445 initial LDLT recipients, and perioperative variables, including platelet count and PT-INR, were assessed for their association with severe complications (Clavien-Dindo classification grade IIIb/IV) and mortality within 90 days after operation.

RESULTS

Severe complications and operative mortality occurred in 161 (36%) and 23 patients (5%), respectively. Cox regression analysis revealed that a high body mass index [hazard ratio (HR) 1.2; 95% confidence interval (CI), 1.1-1.4; P = 0.004] and low platelet count on postoperative day (POD)3 (HR 0.88; 95% CI, 0.57-0.97; P < 0.001) were independent predictors for grade IIIb/IV complications after LDLT, whereas high PT-INR on POD5 (HR 1.1; 95% CI, 1.1-1.3; P = 0.021) was the only independent factor for operative mortality. In addtion, the progonostic scoring with low platelet count (<50 × 10/L) and prolonged prothrombin time (PT-INR >1.6) within POD5, 1 point for each, was demonstrated to be useful in predicting the development of Clavien-Dindo grade IIIb/IV/V complications after LDLT (30% for score 0, 46% for score 1, and 72% for score 2: 0 vs 1, P = 0.004; 0 vs 2, P < 0.001; 1 vs 2, P = 0.002).

CONCLUSIONS

PT-INR above 1.6 and platelet count below 50 × 10/L within POD5 were useful predictors of mortality and severe complications after LDLT.

Venous drainage map of the liver for complex hepatobiliary surgery and liver transplantation

BACKGROUND

Inflow and outflow patency of the liver parenchyma is required to maximize the metabolic function of the liver. However, the definition and distribution of hepatic venous drainage regions has yet to be reported. The aim of this study was to define major hepatic venous tributaries and investigate the mean drainage volume of each territory.

METHODS

Three-dimensional (3D) simulations from the livers of 100 healthy donors were reviewed for living donor liver transplantation to determine the distribution of the significant hepatic venous tributaries and the drainage patterns of each segment.

RESULTS

The left hepatic vein (LHV), middle hepatic vein (MHV), and right hepatic vein (RHV) contributed a mean drainage of 20.7%, 32.7%, and 39.6% of the entire liver, respectively. Accessory hepatic veins accounted for remaining 7.0%. The middle right hepatic vein (MRHV) and inferior right hepatic vein (IRHV) accounted for a mean total drainage of 8.0% and 10.6%, respectively, when they present. In addition, major tributaries of hepatic veins were clearly detected, and their typical distributions were described.

CONCLUSIONS

Knowledge of hepatic venous territories is necessary for complex hepatobiliary surgery. This "venous drainage map" may provide useful information for complex liver surgery and transplantation.

Safety and efficacy of cryopreserved homologous veins for venous reconstruction in pancreatoduodenectomy

BACKGROUND

There are several techniques for reconstructing the portal vein-superior mesenteric vein during pancreatoduodenectomy. The aim of the present study was to present our results with portal vein-superior mesenteric vein reconstruction using cryopreserved homologous veins during pancreatoduodenectomy for patients with pancreatic head cancer.

METHODS

Patients who underwent pancreatoduodenectomy for pancreatic head cancer were reviewed retrospectively. In patients with portal vein-superior mesenteric vein resection, the detailed method of reconstruction and clinical outcomes were reviewed. Clinical characteristics, patient survival, and portal vein-superior mesenteric vein patency were compared between those with and without homologous vein grafts. Factors affecting the patency of reconstructed veins were assessed by univariate analysis.

RESULTS

Among 144 patients undergoing pancreatoduodenectomy, portal vein-superior mesenteric vein resection was performed in 36 patients (25%); 18 (50%) underwent reconstruction with homologous veins, and the other 18 (50%) underwent reconstruction without homologous veins. The extent of portal vein-superior mesenteric vein involvement, operative time, duration of clamping of portal vein-superior mesenteric vein, intraoperative blood loss, and length of the venous resection were greater (P ≤ .013 each) in those with homologous vein grafts. There was no significant difference in postoperative morbidity/mortality, patient survival, or portal vein-superior mesenteric vein patency. The 1- and 2-year overall patency of portal vein-superior mesenteric vein was 76% and 71%, respectively, while the 2-year patencies were 67% and 67% in those with homologous veins and 87% and 73% in those without homologous veins without difference between the groups. Circumferential resection and pathologic portal vein-superior mesenteric vein involvement were associated with the patency of the reconstructed vein (P = .002 and P = .028, resp).

CONCLUSION

Use of homologous venous grafts for portal vein-superior mesenteric vein reconstruction are feasible alternatives during pancreatoduodenectomy for advanced pancreatic head cancer.

Reconstruction of hepatic venous tributary in right liver living donor liver transplantation: The importance of the inferior right hepatic vein

Special care must be taken in hepatic vein reconstruction to avoid outflow block in living donor liver transplantation (LDLT) with a right liver graft. We have used cryopreserved homologous veins to reconstruct the right hepatic vein (RHV), middle hepatic vein (MHV), MHV tributaries (V5 and V8), and inferior right hepatic vein (IRHV). The reconstruction of V5, V8, and IRHV was based on the estimated congestive volume, calculated by the computed tomography volumetry, to secure the functional graft volume of 40% of the recipient standard liver volume. Among 262 right liver LDLT recipients, the number of reconstructed RHVs, MHVs, V5s, V8s, and IRHVs was 262, 48, 110, 111, and 147, respectively, and the overall patency was 95%, 100%, 36%, 58%, and 86%, respectively. Although the patency of the RHVs and MHVs was satisfactory, that of the V5s, V8s, and IRHVs was suboptimal. Patency of the IRHVs (86%, 126/147) was significantly better than that of both V5s (36%, 40/110) and V8s (58%, 64/111; P < 0.001). In addition, the estimated volume drained by IRHVs was significantly greater than that of V5s and V8s (IRHV, 176 ± 92 mL; V5, 105 ± 49 mL; V8, 127 ± 60 mL; P < 0.001). The patency of IRHV was significantly improved by applying the double inferior vena cava method (93%, 94/101) when compared to the direct anastomosis to vena cava (68%, 25/37; P < 0.001). The IRHV functioned as a main drainage route in cases of an obstructed RHV. In conclusion, reconstruction of the IRHV is recommended, not only to improve the functional reserve of the graft, but also to secure multiple drainage routes of the graft.

Outflow reconstruction for right liver allograft with multiple hepatic veins: "V-plasty" of hepatic veins to form a common outflow channel versus 2 or more hepatic vein-to-inferior vena cava anastomoses in limited retrohepatic space

Outflow reconstruction in living donor liver transplantation (LDLT) is certainly difficult in limited retrohepatic space with using right liver grafts with venous anomalies. Venoplasty of the inferior right hepatic veins (IRHVs) and middle hepatic vein (MHV) reconstruction using synthetic grafts to form a common outflow channel or a second venocaval anastomosis are available options. We aim to compare outcomes of LDLT recipients who underwent outflow reconstruction with a "V-Plasty" technique and outcomes of patients who underwent a second venocaval anastomosis. Out of 325 recipients who underwent LDLT from March 2011 to September 2014, 45 received right liver allografts that were devoid of MHV with multiple draining IRHVs (2 or more). Group A (n = 16) comprised the recipients with outflow reconstruction with a V-Plasty, and group B (n = 29) included the recipients with a second venocaval anastomosis. Group A recipients (male:female, 10:6; median age, 50.5 years) had a mean Model for End-Stage Liver Disease score of 14.7, whereas for group B recipients (male:female, 20:9; median age, 52.0 years) it was 17.2. The mean IRHV diameter for group A and B grafts was 8.3 mm each. Mean warm ischemia time for group A was significantly lower (25.2 minutes) as compared to group B recipients (34.6 minutes) with P < 0.001. The 2-month patency rates of vascular grafts were 100% for group A recipients with no evidence of thrombosis. In conclusion, the V-Plasty technique of MHV and IRHV reconstruction to form a common outflow is a new concept that proves to be a safe and feasible alternative for second venocaval anastomosis.