Non-standard hepatic venous reconstruction in the setting of absent inferior vena cava in partial graft pediatric liver transplantation-A matched retrospective cohort study.

Recipient cava may be unavailable for outflow reconstruction in some children undergoing liver transplantation (PLT) due to caval agenesis, tumor, or fibrotic caval occlusion. Non-standard hepatic venous reconstruction (NHVR) with a direct veno-caval anastomosis or neo-cava reconstruction is necessary in such cases. Retrospective review of all PLT needing NHVR performed in our unit from January 2010 to September 2019 was performed. Outcomes of this group were compared to a 2:1 matched control group who underwent transplantation with standard piggyback technique. Fifteen children (4.9%) of 304 PLT recipients underwent NHVR. Caval agenesis in biliary atresia (n = 5, 33%) and hepatoblastoma infiltrating the cava (n = 4, 27%) were the commonest indications. Ten children had neo-cava reconstruction, while 5 had direct anastomosis to the supra-hepatic caval cuff or right atrium. One child had developed neo-cava thrombosis without graft venous outflow obstruction in the post-operative period. There was no significant difference in major morbidity, need for re-operation (20% vs 16.7%; P = 1.00), hospital stay (24 days, vs 21 days; P = .32), graft & patient survival among the study and control groups. Absent or inadequate recipient cava during PLT with a partial liver graft can be safely managed with technical modifications. Results equivalent to standard piggyback implantation can be achieved.

Successful use of the left portal vein as graft for middle hepatic vein reconstruction in left hemihepatectomy: preliminary experience on six cases.

BACKGROUND: The purpose of this research was to assess the feasibility of reconstructing the middle hepatic vein (MHV) with resected left portal vein during left hemihepatectomy. METHODS: From January 2014 to January 2018, six patients received left hemihepatectomy combined with MHV reconstruction using the resected left portal vein in West China Hospital. We reviewed the clinical data including patient details, surgical technique, graft patency, and operative results. RESULTS: All six patients underwent left hemihepatectomy for liver tumors located at left hepatocaval confluence. In these patients, MHV was resected due to tumor invading and reconstructed using the resected left portal vein as graft. The mean operating time was 316 min. Two patients developed complications: one experienced bile leakage and one experienced pleural effusion. No patient developed vascular graft complications. All the grafts remained unobstructed, and no local tumor recurrence occurred during the observation period of 13-41 months. CONCLUSIONS: Our results indicated that the left portal vein was a safe graft for hepatic vein reconstruction. In addition, left hemihepatectomy combined with middle hepatic vein resection and reconstruction using the left portal vein can be performed safely to treat liver tumors located at hepatocaval confluence.

Utility of Polyethylene Terephthalate (Dacron) Vascular Grafts for Venous Outflow Reconstruction in Living-Donor Liver Transplantations.

BACKGROUND: Venous outflow reconstruction of modified right-lobe liver grafts has been shown to prevent the occurrence of graft congestion and subsequent complications, including graft loss. In the present study, we aimed to investigate the safety and efficacy of Dacron grafts for venous reconstruction in living donor liver transplantation (LDLT). METHODS: Between January 2016 and January 2018, Dacron grafts were used in 148 liver transplants. Of these, 104 patients who had a follow-up computerized tomography (CT) scan were enrolled into the study. A total of 179 outflow hepatic veins including V5, V8, partial middle hepatic vein, and accessory inferior right hepatic veins (IRHV) were reconstructed using synthetic Dacron grafts. Graft patency was evaluated with both intraoperative Doppler ultrasonography following reconstruction, and a follow-up CT was performed on the postoperative day 7 (±1). Retrospective data collection included demographics, parameters for small-for-size (laboratory tests [bilirubin, International Normalized Ratio] and ascites) syndrome, postoperative morbidity, and mortality. RESULTS: Follow-up CT revealed graft patency in 155 out of 179 (86.6%) vascular grafts. Postoperative seventh-day patency rates for each reconstructed vein were as follows: V5, 87.5% (70/80); V8, 87.7% (50/57); partial middle hepatic vein, 100% (11/11); and IRHV, 77.4% (24/31). No major graft-related complications (early graft dysfunction, graft infection) or graft-related mortality were observed. None of the recipients developed small-for-size syndrome based on laboratory tests and clinical findings. CONCLUSIONS: Dacron vascular grafts appear as an advantageous and useful alternative for venous outflow reconstruction in LDLT.

Impact of the Inferior Right Hepatic Veins on Right Liver Lobe Regeneration in Living-Donor Liver Transplant: 3-Dimensional Computed Tomography Scan Analyses in Donors and Recipients.

OBJECTIVES: The presence of an inferior right hepatic vein significantly modifies the outflow pattern of the right liver and may have an impact on graft regeneration. MATERIALS AND METHODS: Study patients were donors and recipients with 3-dimensional computed tomography scan simulation. We studied the physiologic impact of the inferior right hepatic veins on right liver regeneration in donors of left lobe grafts (step1; n = 60 patients) and the efficacy of a inferior right hepatic vein reconstruction policy based on a vessel caliber > 5 mm criteria in recipients of right liver grafts (step 2; n = 38 patients). RESULTS: In step 1, the regeneration rate at 1 month was comparable between future liver remnants with inferior right hepatic vein (regeneration rate of 28.3%) and without inferior right hepatic vein (regeneration rate of 30.2%). In step 2, at 3 months after living-donor liver transplant, we observed no significant differences in regeneration rates among grafts anatomically without an inferior right hepatic vein (regeneration rate of 60.7%), grafts with an inferior right hepatic vein but no reconstruction (regeneration rate of 64.9%), and grafts with an inferior right hepatic vein and its reconstruction (regeneration rate of 68.1%). Within the latter subgroup, grafts with a dominant inferior right hepatic vein showed a greater regeneration of the anterior sector with inversion of the anterior-to-posterior sector regeneration ratio compared with right hepatic vein-dominant grafts (inferior right hepatic vein-dominant vs right hepatic vein-dominant showed anterior sector regeneration rates of 85.7% vs 52.1%; P = .02; anterior/posterior sector regeneration ratio was 2.3 vs 0.6, respectively; P = .04). CONCLUSIONS: The reconstruction policy for inferior right hepatic vein with caliber > 5 mm is effective but should be implemented with computed tomography scan simulation. Right lobe grafts with a dominant inferior right hepatic vein are at higher risk of impaired regeneration due to expected large volumes of hepatic venous congestion if the middle hepatic veins tributaries or the inferior right hepatic veins are not reconstructed and an increased rate of right hepatic vein complications.

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

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

Analysis of Risk Factors Affecting the Development of Infection in Artificial Vascular Grafts Used for Reconstruction of Middle Hepatic Vein Tributaries in Living Donor Liver Transplantation.

BACKGROUND: To analyze the risk factors affecting the development of infection in artificial vascular grafts (AVGs) used for reconstruction of middle hepatic vein (MHV) tributaries in living donor liver transplantation (LDLT). METHODS: Between January 2009 and January 2018, 1253 right lobe LDLTs were performed at our Transplant Institute, and MHV tributaries of the 640 right lobe liver grafts were reconstructed with AVG. Reconstructed MHV tributaries were removed due to AVG infection in 25 of these patients (case group; n = 25). To determine risk factors for AVG infection, right lobe LDLT patients without AVG infections were selected as control group (n = 615). Both groups were compared about demographic parameter, transcystic catheter usage, bile leakage, type of biliary anastomosis (duct-to-duct, telescopic duct-to-duct), number of graft biliary duct (=1 versus >1), number of biliary anastomosis (=1 versus >1), AVG thrombosis, AVG types (Dacron versus polytetrafluoroethylene). Univariate analyses were used for comparison of different variables, and variables with P ≤ 0.20 were taken into logistic regression model. RESULTS: Univariate analysis shows that statistically significant differences were found between groups regarding bile leakage (P < 0.001), graft thrombosis (P = 0.002), transcystic catheter (P = 0.049), and AVG types (P = 0.013). Variables with P ≤ 0.20 were taken into logistic regression model. Multivariate analysis shows that bile leakage (odds ratio, 13.3) and AVG thrombosis (odds ratio, 9.8) were determined as independent and strong risk factors for development of AVG infection. CONCLUSIONS: This study revealed that bile leakage and graft thrombosis are independent and strong risk factors for infections of AVGs used for anterior sector drainage reconstruction.

The influence of the middle hepatic vein and its impact on outcomes in right lobe living donor liver transplantation.

BACKGROUND: In adult right lobe living donor liver transplantation, the decision to include the middle hepatic vein (MHV) remains controversial. METHODS: A retrospective analysis of 50 R-LDLTs between January 2008 and June 2016 was performed. RESULTS: Twenty-one procedures were performed using a MHV+ graft (42.0%) and 29 procedures using a MHV- graft (58%). MHV- donors were taller (173 vs 166 cm, p = 0.004) with a larger standard liver volume (1351 vs 1245 mls, p = 0.014) compared to MHV+ donors. The duration of operation for donors was significantly longer in the MHV+ group (530 (313-975) mins) compared to the MHV- group (489 (336-708) mins) (p = 0.029). Similarly, the operative time for recipients was longer in the MHV+ group (660 (428-831) mins) compared to MHV- (579 (359-1214) mins) (p = 0.023). MHV- grafts were heavier compared to MHV+ grafts (918 vs 711 g, p = 0.017). Recipient mortality rates and Kaplan-Meier survival analysis were comparable (p = 0.411). All donors were well at last review. CONCLUSION: Both MHV+ and MHV- grafts are safe for the donor and recipient. The decision to take the MHV should be based on specific donor-recipient characteristics.

Doppler ultrasound follow-up of middle hepatic vein tributaries-interposition vessel graft in recipients of living donor liver transplantation using modified right lobe grafts.

OBJECTIVE: To investigate the value of Doppler ultrasound (US) in recipients of living donor liver transplantation (LDLT) using modified right-lobe grafts (mRLGs) with obstruction of the middle hepatic vein tributaries (MHVTs)-interposition vessel graft (IVG). METHODS: This study included 240 consecutive LDLT recipients in whom 564 MHVTs (>5 mm) were reconstructed using IVG. Regular follow-up Doppler US was performed to assess the patency of the MHVTs-IVG and, if there was an obstruction, to evaluate for the establishment of collateral drainage. MHVTs with obstruction were subdivided into those with and without intrahepatic veno-venous collaterals on Doppler US and were correlated with CT scans. RESULTS: MHVTs-IVG obstruction was identified in 137 patients with 227 MHVTs on follow-up Doppler US (6.2  ±  4.7 months). 90 patients with 149 MHVTs in whom the time interval between Doppler US and contrast-enhanced dynamic CT scans was <1 week were classified into either collateral (68 patients with 121 MHVTs) or non-collateral (22 patients with 28 MHVTs) groups. The presence of intrahepatic veno-venous collaterals on Doppler US were significantly related to no remarkable hepatic venous congestion on CT by both per-patient and per-vein analyses (66 of 68 patients (97.1%) and 118 of 121 MHVTs (97.5%), p < 0.001 and p < 0.001, respectively). CONCLUSION: On Doppler US follow-up of LDLT recipients using mRLGs, identification of intrahepatic veno-venous collaterals associated with obstruction of MHVTs-IVG suggests no remarkable hepatic venous congestion. Advances in knowledge: When an obstruction of a MHVTs-IVG is encountered on Doppler US follow-up of LDLT recipients using mRLGs, no further evaluation with CT is warranted if intrahepatic veno-venous collaterals are observed on Doppler US, as this finding suggests no remarkable hepatic congestion.

Malposition of a Peripherally Inserted Central Venous Catheter in the Graft Hepatic Vein.

Central venous catheters are used for delivering medications and parenteral nutrition, measuring hemodynamic variations, and providing long-term intravenous access. In our clinic, during liver transection using a living-liver donor, peripherally inserted central venous catheters are generally preferred because they involve a less invasive technique with a lower risk of complications. In this report, we present the case of a 36-year-old male liver donor into whom we peripherally inserted a central venous catheter from his left basilic vein. After transecting the hepatic vein, the surgeon found foreign material inside the venous lumen, which turned out to be the distal segment of the catheter.

Outcomes of long storage times for cryopreserved vascular grafts in outflow reconstruction in living donor liver transplantation.

The outflow reconstruction of the right anterior sector in a right liver graft (RLG) with cryopreserved vascular grafts (CVGs) is crucial for preventing graft congestion in living donor liver transplantation (LDLT). The impact of the duration of cryopreservation has not been evaluated so far. From 2006 to 2009, 250 LDLT were performed: 47 of these patients (group 1) received CVGs stored for ≦1 year, and 33 patients (group 2) received CVGs stored for >1 year. Single or multiple segment 8 hepatic veins were reconstructed. The number of anastomoses did not affect vascular graft patency (P = 0.21). The length of the cryopreservation time did not affect the histological findings for CVGs. The preoperative and postoperative liver graft volumes were 783.8 ± 129.7 and 1102 ± 194.7 cc, respectively, for group 1 and 753.7 ± 158.5 and 1097.2 ± 178.7 cc, respectively, for group 2. The regeneration indices for liver grafts in the whole patient group, group 1, and group 2 were 48.9%, 47.4%, and 51.05%, respectively. In conclusion, the storage duration has no impact on the patency of CVGs in outflow reconstruction or on the regeneration of RLGs in LDLT. CVGs stored for >1 year can be safely used for the outflow reconstruction of RLGs in LDLT.

[The role of the middle hepatic vein in the living donor liver transplantation with right hemiliver]. / Rolul venei hepatice medii în transplantul hepatic de la donator viu cu hemificat drept.

BACKGROUND: Living donor liver transplantation has appeared and developed as a consequence to the shortage of organs. In case of right hemiliver procurement, the role of the middle hepatic vein is crucial for the prevention of right anterior section congestion and the promotion of liver regeneration. MATERIAL AND METHOD: We performed a retrospective study on a group of 36 adult patients who underwent living donor liver transplantation with right hemiliver in Fundeni Clinical Institute, having as a major indication liver cirrhosis. Concerning the middle hepatic vein, this was procured in 10 cases, not procured nor reconstructed in another 10 cases, and reconstructed on the bench in 16 cases. RESULTS: The immediate postoperative survival was roughly 91%, with 7 cases of "small for size syndrome", 2 cases being retransplanted. CONCLUSIONS: In case of living donor liver transplantation with the right hemiliver, the reconstruction of the middle hepatic vein helps the liver regeneration and prevent the "small for size" syndrome.

Estudios volumétricos y anatómicos en el donante vivo / No disponible

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Usability of ringed polytetrafluoroethylene grafts for middle hepatic vein reconstruction during living donor liver transplantation.

Large vein allografts are suitable for middle hepatic vein (MHV) reconstruction, but their supply is often limited. Although polytetrafluoroethylene (PTFE) grafts are unlimitedly available, their long-term patency is relatively poor. We intended to enhance the clinical usability of PTFE grafts for MHV reconstruction during living donor liver transplantation (LDLT). Two sequential studies were performed. First, PTFE grafts were implanted as inferior vena cava replacements into dogs. Second, in a 1-year prospective clinical trial of 262 adults undergoing LDLT with a modified right lobe, MHV reconstruction with PTFE grafts was compared with other types of reconstruction, and the outcomes were evaluated. In the animal study, PTFE grafts induced strong inflammatory reactions and luminal thrombus formation, but the endothelial lining was well developed. In the clinical study, the reconstruction techniques were revised to make a composite PTFE graft with an artery patch on the basis of the results of the animal study. MHVs were reconstructed with cryopreserved iliac veins (n = 122), iliac arteries (n = 43), aortas (n = 13), and PTFE (n = 84), and these reconstructions yielded 6-month patency rates of 75.3%, 35.2%, 92.3%, and 76.6%, respectively. The overall 6-month patency rates for the iliac vein and PTFE grafts were similar (P = 0.92), but the 6-month patency rates with vein segment 5 were 51.0% and 34.7%, respectively (P = 0.001). The overall graft and patient survival rates did not differ among these 4 groups. In conclusion, ringed PTFE grafts combined with small vessel patches showed high patency rates comparable to those of iliac vein grafts; thus, they can be used for MHV reconstruction when other sizable vessel allografts are not available.

Living donor right hepatectomy with inclusion of the middle hepatic vein: outcome in 200 donors.

Venous congestion of segments V and VIII of the graft is observed frequently in right-lobe living donor liver transplants (LDLT) without middle hepatic vein (MHV) drainage. It can cause graft dysfunction and failure. Inclusion of the MHV in the right lobe graft allows optimal venous drainage but can pose adverse effects for the donor. From May 2005 to April 2011, we performed 202 right-lobe LDLTs using grafts that all (except two) contained the MHV. The mean duration of donor surgery was 558±132 minutes (median 540, range 332-1100), and estimated blood loss 441±309 mL (median 350, range 35-3200). No donor was admitted to the intensive care unit postoperatively. The mean hospital stay was 8.7±2.1 days (median 8, range 6-22). Postoperatively, 39 donors (19.5%) experienced Clavien grade I and II complications, mostly minor wound infections or massive ascites necessitating diuretic therapy. Seven (3.5%) donors displayed Clavien grade III complications, including five bile leakages requiring endoscopic retrograde biliary drainage and two abdominal wound dehiscences requiring repair under general anesthesia. There was no donor death. In conclusion, inclusion of the MHV in a right-lobe LDLT was safe for most donors.

Right lobe living-donor liver transplantation with or without middle hepatic vein: a meta-analysis.

OBJECTIVE: The purpose of this meta-analysis was to compare outcomes after right-lobe living-donor liver transplantation (LDLT) with or without the middle hepatic vein (MHV). METHODS: Studies were identified through a computerized search of Pubmed, Embase, Ovid, the Cochrane Hepato-Biliary Group Controlled Trials Register, the Cochrane Central Register of Controlled Trials, the Cochrane Library database, and the Web of Science. Two reviewers independently assessed the quality of each study and abstracted outcome data. We extracted data for liver functional recovery in donors, donor hospital stay, donor complications and liver functional recovery in recipients. We synthesized published data using random-effects and fixed-effect models, expressing results as weighted mean differences (WMD) or relative risk (RR). RESULTS: The 11 included eligible studies came from medical centers worldwide. Significant differences between "with MHV" versus "without MHV" groups were not observed for liver functional recovery (P=.08; WMD=-2.88), donor hospital stay (P=.00; WMD=0.00), or donor complications (P=.90; RR=1.02). However, our meta-analysis showed a significant benefit for recipients liver functional recovery favoring the MHV group (P=.02; WMD=-33.06). CONCLUSIONS: Our meta-analysis discovered that right lobes with MHV not only experienced better liver functional recovery in recipients, but also caused no greater harm or risk to donors.

Hepatocyte transplantation through the hepatic vein: a new route of cell transplantation to the liver.

The efficiency of hepatocyte transplantation into the liver varies with the method of administration. This study investigated whether retrograde infusion via the hepatic vein provides a sufficient number of donor cells for the liver. Donor hepatocytes were isolated from dipeptidyl peptidase IV (DPPIV(+)) rats and transplanted into DPPIV(-) rat livers either by antegrade portal vein infusion or retrograde hepatic vein infusion. Hepatocyte engraftment ratios and localization were evaluated by histological DPPIV enzymatic staining at 1 week and 8 weeks after the transplantation. No significant differences in engraftment efficiency were observed at either 1 week or 8 weeks after transplantation by either route. However, the localization of the transplanted hepatocytes differed with the administration route. Portal vein infusion resulted in predominantly periportal engraftment, whereas hepatic vein infusion led to pericentral zone engraftment. Immunohistochemical analysis showed that the transplanted hepatocytes engrafted in the pericentral zone after retrograde infusion displayed intense CYP2E1 staining similar to the surrounding native hepatocytes. CYP2E1 staining was further enhanced by administration of isosafrole, an inducing agent for various cytochrome P450 enzymes, including CYP2E1. This study demonstrates a novel approach of transplanting hepatocytes into the liver through retrograde hepatic vein infusion as the means to target cell implantation to the pericentral zone.

Unusual presentation of left hepatic vein in deceased donor: case report.

An anomaly of the left hepatic vein was discovered in a deceased donor for whole liver transplantation. This vein was attached by a thin bridge of tissue to the suprahepatic inferior vena cava cuff, which received the right and middle hepatic vein in a common trunk. The left hepatic vein and the common trunk drained together into the right atrium. The thin bridge of tissue connecting the 2 independent vessels was severed, and ex situ reduction of the left lateral segments was using a harmonic scalpel. Although a graft with reduced size is not ideal, ex situ reduction should be considered a valuable option when viability of the left lateral segments is uncertain in the donor or at the back table.

Donor/recipient algorithm for management of the middle hepatic vein in right graft live donor liver transplantation.

BACKGROUND: The aim of this study was to delineate an algorithm for donor and recipient criteria and middle hepatic vein (MHV) management in right-graft live-donor liver transplantation (LDLT) on the basis of computerized 3-dimensional computed tomographic image analysis. METHODS: Data on 94 consecutive right-graft LDLTs were prospectively collected. Graft and remnant data for the first 23 cases were retrospectively evaluated by means of 3-dimensional computed tomographic reconstructions, and on the basis of that preliminary series, a graft selection algorithm using 3 parameters-hepatic vein dominance classification, graft and remnant graft volume/body weight ratios, and congestion volumes-was created. It was subsequently applied to the next 71 right-graft LDLTs. RESULTS: Fifty-nine right grafts contained the MHV. Four of the 12 grafts with no MHVs required MHV reconstructions. In 18 cases, small liver grafts were used. The postoperative function of liver grafts and remnants with versus without MHVs was not statistically different. CONCLUSIONS: The proposed algorithm favored the inclusion of the MHV with the right grafts. It also allowed for the procurement of grafts that were potentially small for size without compromising donor or recipient safety.