Sequential vs simultaneous revascularization in patients undergoing liver transplantation: A meta-analysis

Simultaneous embolization of the right portal and hepatic veins before intrahepatic cholangiocarcinoma resection

Major liver resections require extensive margins. Occasionally, insufficient parenchyma is available after surgery to maintain liver function. In such cases, vascular embolization in the affected lobe is necessary to induce contralateral lobe hypertrophy. We present a case of embolization of the right portal and hepatic veins prior to intrahepatic cholangiocarcinoma resection. Embolization was performed because of insufficient residual parenchyma on imaging studies. The patient recovered well with no signs of liver failure, and remains in remission at 3 years postoperatively. Knowledge of the use of this technique in association with surgical resection can reduce postoperative complications and allow the removal of larger tumors than those previously considered borderline.

Histological Assessment of the Bile Duct before Liver Transplantation: Does the Bile Duct Injury Score Predict Biliary Strictures?

INTRODUCTION

Histological injury to the biliary tree during organ preservation leads to biliary strictures after liver transplantation. The Bile Duct Injury (BDI) score was developed to assess histological injury and identify the grafts most likely to develop biliary strictures. The BDI score evaluates the bile duct mural stroma, peribiliary vascular plexus (PVP) and deep peribiliary glands (DPGs), which were correlated with post-transplant biliary strictures. However, the BDI score has not been externally validated. The aim of this study was to verify whether the BDI score could predict biliary strictures at our transplant centre.

METHODS

Brain-dead donor liver grafts transplanted at a single institution from March 2015 to June 2016 were included in this analysis. Bile duct biopsies were collected immediately before transplantation and assessed for bile duct injury by two blinded pathologists. The primary outcome was the development of clinically significant biliary strictures within 24 months post-transplant.

RESULTS

Fifty-seven grafts were included in the study which included 16 biliary strictures (28%). Using the BDI score, mural stromal, PVP and DPG injury did not correlate with biliary strictures including Non-Anastomotic Strictures. Severe inflammation (>50 leucocytes per HPF) was the only histological feature inversely correlated with the primary outcome (absent in the biliary stricture group vs. 41% in the no-stricture group, p = 0.001).

CONCLUSIONS

The current study highlights limitations of the histological assessment of bile duct injury. Although all grafts had bile duct injury, only inflammation was associated with biliary strictures. The BDI score was unable to predict post-transplant biliary strictures in our patient population.

Could retrograde reperfusion combined with washout technique broaden the applicability of marginal grafts in liver transplantation? Intra-operative and short-term outcomes of a prospective cohort

INTRODUCTION

many revascularization techniques were designed to reduce the imbalance of ischemia-reperfusion injury. This study's objective is to evaluate retrograde reperfusion (RR) compared to sequential anterograde reperfusion (AR), with and without the washout technique (WO).

METHOD

this prospective cohort study collected data from 94 deceased donor orthotopic liver transplants and divided it into three groups: RR with WO (RR+WO), AP with WO (AR+WO), and AP without WO (AR). This study did not assign the reperfusion technique to the participants. The primary outcome considered the early graft dysfunction, and secondary outcomes included post-reperfusion syndrome (PRS), post-reperfusion lactate, surgery fluid balance, and vasoactive drug dose during the surgery.

RESULTS

87 patients were submitted to the final analysis-29 in the RR+WO group, 27 in the AR+WO group, and 31 in the AR group. Marginal grafts prevalence was not significantly different between the groups (34% vs. 22% vs. 23%; p=0.49) and early graft dysfunction occurred at the same rate (24% vs. 26% vs. 19%; p=0.72). RR+WO reduced serum post-reperfusion lactate (p=0.034) and the incidence of significant PRS (17% vs. 33% vs. 55%; p=0.051), but norepinephrine dosing >0.5mcg/kg/min were not different during the surgery (20,7% vs. 29,6% vs. 35,5%, p=0.45).

CONCLUSIONS

primary outcome was not significantly different between the groups; however, intraoperative hemodynamic management was safer using the RR+WO technique. We theorized that the RR+WO technique could reduce the incidence of PRS and benefit marginal graft survival following diseased donor orthotopic liver transplantation.

Effects of Initial Hepatic Artery Followed by Portal Reperfusion Technique on Deceased Donor Liver Transplant Outcomes

OBJECTIVES

Although initial portal vein reperfusion of a liver allograft is nearly standardized, limited data suggest initial hepatic artery reperfusion may improve hemodynamics and posttransplant outcomes.

MATERIALS AND METHODS

We retrospectively reviewed orthotopic liver transplants performed between January 2013 and February 2018. Parameters of liver recipients with initial hepatic artery reperfusion were compared with those with initial portal vein reperfusion.

RESULTS

Of 204 recipients, 53 (26%) were initially perfused from the hepatic artery and 151 (74%) were initially perfused from the portal vein. Demographics between groups did not differ. There were no significant differences in the incidence of acute rejection between recipients with initial hepatic artery reperfusion versus portal vein reperfusion at 3 months and 1 year (1.9% vs 7.9% and 7.5% vs 10.6%; not significant), hepatic artery thrombosis (1.9% vs 4.0% and 1.9% vs 7.3%; not significant), biliary leakage (7.5% vs 4.0% and 9.4 vs 6.6; not significant), biliary strictures (7.5% vs 5.3% and 11.3% vs 7.9%; not significant), or portal or hepatic venous thrombosis/stenosis (5.7% vs 5.3% and 7.5% vs 7.9%; not significant). Furthermore, recipients with initial hepatic artery reperfusion and portal vein reperfusion were both hospitalized for a median of 8.5 days (interquartile range, 6.5-15.5 vs 7.0-14.0 days, respectively), and both groups were in the intensive care unit for a median of 3 days (interquartile range, 2-7 vs 2-4 days, respectively). Initial hepatic artery reperfusion was associated with significantly less intraoperative packet red blood cell transfusion (median, 11.9 U [interquartile range, 11.1-13.1 U] vs 15.5 U [interquartile range, 12.9-17.9 U]; P < .001). The 2 groups did not differ in terms of patient and graft survival.

CONCLUSIONS

Initial reperfusion of liver allografts with arterial, rather than portal, blood has benefits to hemodynamic stability, did not have deleterious effects on outcomes, and resulted in less intraoperative blood utilization.

Short- and Long-Term Outcomes of Different Reperfusion Sequences in Liver Transplantation

Background

Although most centers perform primary portal vein reperfusion (PV) in orthotopic liver transplantation (OLT) for historical reasons, there is so far no sound evidence as to whether this technique is superior. The present study evaluated the long-term outcome of 3 different reperfusion sequences: PV vs primary arterial (A) vs simultaneous reperfusion (SIM).

Material/Methods

All patients at our center who underwent OLT (who received a primary, whole-organ liver graft) from 2006 to 2007 were evaluated for analysis.

Results

A total of 61 patients were found eligible (PV: 25, A: 22, SIM: 14). Twenty-one patients (35%) were still alive after the follow-up period of 12 years. Despite poorer starting conditions such as higher recipient age (59 y (SIM) vs 55 y (A) vs 50 y (PV), P=0.01) and donor age (56 y (SIM) vs 51 y (PV) vs 50 y (A), n.s.), higher MELD scores (22 vs 19 (PV) vs 17 (A), n.s.), as well as a higher number of marginal donor organs (79% (SIM) vs 36% (A/PV), P=0.02), SIM-recipients demonstrated superior outcomes. Overall survival was 8.1 y (SIM), 4.8 y (PV), and 5.9 y (A, n.s.)). None of the SIM-recipients underwent re-transplantation, while the rate was 32% in the PV-group. The 8.1 y graft survival in SIM-recipients was significantly longer than in the other 2 groups, which were 3.3 y (PV) and 5.5 y (A, P=0.013).

Conclusions

Although SIM-reperfused recipients were the oldest and received grafts of inferior quality, these recipients showed superior results in terms of overall patient and graft survival. Multicentric randomized controlled trials with larger study populations are required to confirm this finding.

Heterogeneity of Bile Duct Management in the Development of Ischemic Cholangiopathy After Liver Transplantation: Results of a European Liver and Intestine Transplant Association Survey

BACKGROUND

Surgical factors and direct cytotoxicity of bile salts on cholangiocytes may play a role in the development of ischemic cholangiopathy (IC) after liver transplantation (LTx). There is no validated consensus on how to protect the bile ducts during procurement, static preservation, and LTx. Meanwhile, IC remains the most troublesome complication after LTx.

AIM

To characterize bile duct management techniques during the LTx process among European transplant centers in cases of donation after brain death (DBD) and circulatory death (DCD).

METHOD

An European Liver and Intestine Transplant Association-European Liver Transplant Registry web survey designed to conceal respondents' personal information was sent to surgeons procuring and/or transplanting livers in Europe.

RESULTS

Sixty-five percent of responses came from large transplant centers (>50 procurements/y). In 8% of DBDs and 14% of DCDs the bile duct is not rinsed. In 46% of DBDs and 52% of DCDs surgeons prefer to remove the gallbladder after graft reperfusion. Protocols concerning preservation solutions (nature, pressure, volume) are extremely heterogeneous. In 54% of DBDs and 61% of DCDs an arterial back table pressure perfusion is performed. Steroids (20%-10%), heparin (72%-60%), prostacyclin (3%-7%), and fibrinolytics (4%-11%) are used as donor-protective interventions in DBD and DCD cases, respectively. In 2% of DBD and 6% of DCD cases a hepatic artery reperfusion is performed first. In 4% of DBD and 6% of DCD cases, fibrinolytics are administered through the hepatic artery during the bench and/or implantation.

CONCLUSION

This European web survey shows for the first time the heterogeneity in the management of bile ducts during procurement, preservation, and transplantation in Europe. In the context of sharing more marginal liver grafts, an expert meeting must be organized to formulate guidelines to be applied to protect liver grafts against IC.

Order of liver graft revascularization in deceased liver transplantation: A systematic review and meta-analysis

BACKGROUND

The ideal order for liver graft revascularization during liver transplantation remains unknown. The majority of liver transplant centers prefer portal venous reperfusion followed by arterial reperfusion to shorten the warm ischemia time. The aim of this study was to review the different revascularization techniques used in clinical liver transplantation to identify any potential clinical benefits.

METHODS

A systematic search of 5 databases was performed to identify all available original articles that reported liver transplantation and compared different techniques of reperfusion. The primary outcomes were patient and graft survival. Secondary outcomes were defined by postreperfusion syndrome, primary nonfunction, vascular complications, biliary complications, and retransplantation.

RESULTS

A total of 1,160 patients undergoing liver transplantation from 15 studies were included in this review and meta-analysis. There were no differences regarding the 1-year patient and graft survival for the revascularization techniques. The incidence of primary nonfunction, vascular complications, and retransplantation did not differ between the groups. Although there were no differences regarding biliary complications between the different groups, there were more nonanastomotic strictures in patients with initial portal revascularization (9%) compared with those with simultaneous revascularization (2%; risk ratio 1.07; 95% confidence interval, 1.00-1.14; P = .05; I² = 51%).

CONCLUSION

The order of liver graft revascularization does not influence patient and graft survival. Each revascularization technique offers potential benefits that can be used under specific clinical situations.

The role of graft reperfusion sequence in the development of non-anastomotic biliary strictures following orthotopic liver transplantation: A meta-analysis

BACKGROUND

Liver transplant is a potential cure for liver failure and hepatic malignancy but there are many techniques which have been described for vascular reconstruction. This study was to compare the prevalence of non-anastomotic biliary stricture and other surgical complications based on Clavien-Dindo scoring system, in initial portal reperfusion (sequential) versus simultaneous or initial artery reperfusion.

DATA SOURCES

Meta-analysis of published studies comparing the outcomes of both techniques was carried out. Data search was conducted across the major databases and studies were selected under the guidance of the Cochrane guidelines for systematic reviews and meta-analysis.

RESULTS

Seven studies were included to address the primary and the secondary outcomes. No statistical difference was found in the incidence of non-anastomotic biliary strictures (OR = 0.40; P = 0.14), regardless of reperfusion technique. The pooled estimate of the Clavien-Dindo grading of complications was not significantly different between the techniques, though Clavien-Dindo II complications were higher in the simultaneous or initial artery reperfusion group than the initial portal reperfusion group (OR = 2.73; P = 0.01). Similarly, there was no difference in the operative time, hospital stay and other outcomes addressed in this report.

CONCLUSIONS

The available evidence suggests that there is no significant difference demonstrated in the rate of non-anastomotic biliary strictures or other complications, between the two techniques, except for Clavien-Dindo II complications.

The use of porcine corrosion casts for teaching human anatomy

In teaching and learning human anatomy, anatomical autopsy and prosected specimens have always been indispensable. However, alternative methods must often be used to demonstrate particularly delicate structures. Corrosion casting of porcine organs with Biodur E20^® Plus is valuable for teaching and learning both gross anatomy and, uniquely, the micromorphology of cardiovascular, respiratory, digestive, and urogenital systems. Assessments of casts with a stereomicroscope and/or scanning electron microscope as well as highlighting cast structures using color coding help students to better understand how the structures that they have observed as two-dimensional images actually exist in three dimensions, and students found using the casts to be highly effective in their learning. Reconstructions of cast hollow structures from (micro-)computed tomography scans and videos facilitate detailed analyses of branching patterns and spatial arrangements in cast structures, aid in the understanding of clinically relevant structures and provide innovative visual aids. The casting protocol and teaching manual we offer can be adjusted to different technical capabilities and might also be found useful for veterinary or other biological science classes.

Early prophylactic anticoagulation for portal vein system thrombosis after splenectomy: A systematic review and meta-analysis

A systematic review and meta-analysis were conducted to evaluate the efficacy and safety of early prophylactic anticoagulation for the prevention of portal vein system thrombosis (PVST) after splenectomy. A systematic search of the PubMed, EMBASE, Springer and Cochrane Library databases was performed to identify studies comparing the outcomes in patients receiving or not receiving regular prophylactic anticoagulation after splenectomy. The quality of the included studies was assessed using the Jadad Score and the Newcastle-Ottawa Scale. Heterogeneity was evaluated using the χ² and I² tests. The parameters that were analyzed included the incidence of PVST and anticoagulation-associated complications. A total of seven studies qualified for the review, involving 383 and 283 patients receiving or not receiving regular prophylactic anticoagulation, respectively. The incidence of PVST was significantly reduced with an odds ratio (OR) of 0.31 [95% confidence interval (CI), 0.21-0.46; P<0.00001] in the regular prophylactic anticoagulation group compared with the control group. No difference in the incidence of anticoagulation-associated complications was identified between the two groups (OR=0.60, 95% CI, 0.23-1.56; P=0.30). Early prophylactic anticoagulation was associated with a reduced incidence of PVST, although it was not associated with the incidence of anticoagulation-associated complications. These results indicate that prophylactic anticoagulation could be safely administered after splenectomy, even to cirrhotic patients.