Reducing bile leak following segmental liver transplantation: understanding biliary anatomy of the caudate lobe

Fates of retained hepatic segment IV and its prognostic impact in adult split liver transplantation using an extended right liver graft

PURPOSE

When splitting a liver for adult and pediatric graft recipients, the retained left medial section (S4) will undergo ischemic necrosis and the right trisection graft becomes an extended right liver (ERL) graft. We investigated the fates of the retained S4 and its prognostic impact in adult split liver transplantation (SLT) using an ERL graft.

METHODS

This was a retrospective analysis of 25 adult SLT recipients who received split ERL grafts.

RESULTS

The mean model for end-stage liver disease (MELD) score was 27.3 ± 10.9 and graft-recipient weight ratio (GRWR) was 1.98 ± 0.44. The mean donor age was 26.5 ± 7.7 years. The split ERL graft weight was 1,181.5 ± 252.8 g, which resulted in a mean GRWR of 1.98 ± 0.44. Computed tomography of the retained S4 parenchyma revealed small ischemic necrosis in 16 patients (64.0%) and large ischemic necrosis in the remaining 9 patients (36.0%). No S4-associated biliary complications were developed. The mean GRWR was 1.87 ± 0.43 in the 9 patients with large ischemic necrosis and 2.10 ± 0.44 in the 15 cases with small ischemic necrosis (P = 0.283). The retained S4 parenchyma showed gradual atrophy on follow-up imaging studies. The amount of S4 ischemic necrosis was not associated with graft (P = 0.592) or patient (P = 0.243) survival. A MELD score of >30 and pretransplant ventilator support were associated with inferior outcomes.

CONCLUSION

The amount of S4 ischemic necrosis is not a prognostic factor in adult SLT recipients, probably due to a sufficiently large GRWR.

The Application of Interventional Radiology in Living-Donor Liver Transplantation

Owing to improvements in surgical techniques and medical care, living-donor liver transplantation has become an established treatment modality in patients with end-stage liver disease. However, various vascular or non-vascular complications may occur during or after transplantation. Herein, we review how interventional radiologic techniques can be used to treat these complications.

Prognosis of Split Liver Transplantation Compared with Whole Liver Transplantation in Adult Patients: Single-center Results under the Korean MELD Score-based Allocation Policy

BACKGROUND

Split liver transplantation (SLT) has been occasionally performed in Korea. This study compared the incidence and prognosis of SLT with whole liver transplantation (WLT) in adult patients.

METHODS

Between June 2016 and November 2019, 242 adult patients underwent a total of 256 deceased donor liver transplantation operations. SLT was performed in 7 patients (2.9%).

RESULTS

The mean age of SLT donors was 29.7 ± 7.4 years, and the mean age of recipients was 55.7 ± 10.6 years, with the latter having a mean model for end-stage liver disease score of 34.6 ± 3.1. Mean split right liver graft weight was 1,228.6 ± 149.7 g and mean graft-recipient weight ratio was 1.97 ± 0.39. Of the seven SLT recipients, Korean Network for Organ Sharing (KONOS) status was one in status 1, one in status 2 and five in status 3. The graft (P = 0.72) and patient (P = 0.84) survival rates were comparable in the SLT and WLT groups. Following propensity score matching, graft (P = 0.61) and patient (P = 0.91) survival rates remained comparable in the two groups. Univariate analysis showed that pretransplant ventilator support and renal replacement therapy were significantly associated with patient survival, whereas KONOS status category and primary liver diseases were not. Multivariate analysis showed that pretransplant ventilator support was an independent risk factor for patient survival.

CONCLUSION

Survival outcomes were similar in adult SLT and WLT recipients, probably due to selection of high-quality grafts and low-risk recipients. Prudent selection of donors and adult recipients for SLT may expand the liver graft pool for pediatric patients without affecting outcomes in adults undergoing SLT.

Improved visualization of a fine intrahepatic biliary duct on drip infusion cholangiography-computed tomography: Impact of knowledge-based iterative model reconstruction

AIM

The purpose of this study was to investigate the visualization of fine biliary ducts with knowledge-based iterative model reconstruction (IMR) in low-dose drip infusion computed tomography (CT) cholangiography (DIC-CT) as compared with filtered back projection (FBP) and hybrid iterative reconstruction (iDose⁴ ).

METHODS

A total of 38 patients underwent DIC-CT for living donor liver transplantation. CT was performed approximately 20 min after the end of the infusion of meglumine iotroxate (100 mL). Images were reconstructed using FBP, iDose⁴ , and IMR, and 1-mm slice images at fixed window level and width were prepared for assessment. Two reviewers independently evaluated the quality of visualization of the fine biliary ducts of the caudate lobe (B1) using a 5-point scale. The visualization scores of three reconstructed images were compared using the Kruskal-Wallis test and Mann-Whitney U-test.

RESULTS

For reviewer 1, the visualization score of IMR was significantly higher than that of FBP (P = 0.012), and tended to be higher than that of iDose⁴ (P = 0.078). For reviewer 2, the visualization score of IMR was significantly higher than those of both FBP and iDose⁴ (P < 0.01).

CONCLUSIONS

IMR showed better visualization of B1 on DIC-CT than FBP or iDose⁴ . DIC-CT reconstructed with IMR may be useful to the anatomical grasp of biliary tracts in cases of hepatectomy.

Analysis of caudate lobe biliary anatomy and its implications in living donor liver transplantation - a single centre prospective study

Biliary complications are a significant cause of morbidity after living donor liver transplant (LDLT). Bile leak may occur from bile duct (anastomotic site in recipient and repaired bile duct stump in donor), cystic duct stump, cut surface pedicles or from divided caudate ducts. The first three sites are amenable to post-operative endoscopic stenting as they are in continuation with biliary ductal system. However, leaks from divided isolated caudate ducts can be stubborn. To minimize caudate duct bile leaks, it is important to understand the anatomy of hilum with attention to the caudate lobe biliary drainage. This single-centre prospective study of 500 consecutive LDLTs between December 2011 and December 2016 aims to define the biliary anatomy of the caudate lobe in liver donors based on intraoperative cholangiograms (IOCs) with special attention to crossover caudate ducts and to study their implications in LDLT. Caudate ducts were identified in 468 of the 500 IOCs. Incidence of left-to-right crossover drainage was 61.37% and right to left was 21.45%. Incidence of bile leak in donors was 0.8% and in recipients was 2.2%. Proper intraoperative identification and closure of divided isolated caudate ducts can prevent bile leak in donors as well as recipients.

Changing pattern of biliary complications in an evolving liver transplant unit

Biliary complications (BCs) remain a significant cause of morbidity following liver transplantation (LT). This series of 640 LT recipients with a blend of living and deceased donor transplants was analyzed to determine the incidence, risk factors, management protocol, and outcomes in these patients. Review of a prospectively collected database of transplant recipients operated between August 2009 and June 2016 was performed. Patients were divided into those with and without BCs and data analyzed. The 640 LT recipients from both living (n = 481) and deceased donors (n = 159) were evaluated for BCs. The overall incidence of BCs was 13.7%. It reduced from 23% to 5% (P = 0.003) over a 6-year period. Risk factors for BCs on multivariate analysis were living donor liver transplantation, prolonged time to rearterialization, recipient age above 16 years, prolonged cold ischemia time (CIT) after deceased donor liver transplantation, and biliary reconstruction performed by anyone but the senior author. One-fifth of bile leaks progressed to strictures, and 40% of strictures followed leaks. Endoscopic therapy resolved 60% of the strictures. Surgical repair of strictures was successful in 90% of those in whom endoscopy failed, those who could not undertake the follow-up schedules endoscopic therapy entails, and those presenting with late strictures. BCs significantly prolonged hospital stay but did not alter survival after LT. BCs affect 1 in 7 recipients, although they are not associated with increased mortality. The frequency of these complications is influenced by potentially modifiable factors like evolving surgical expertise and CIT. Liver Transplantation 23 478-486 2017 AASLD.

Improving graft survival by understanding the mechanism of segment 4 complications after split liver transplantation

BACKGROUND

This study was designed to assess the actual mechanism of segment 4 (S4)-related complications after split liver transplantation (SLT) and their impact on graft and overall survival with reference to those of left lateral sectionectomy for pediatric living donor liver transplantation (LLSLD).

METHODS

Clinical data from 53 SLT recipients and 62 LLSLD patients were assessed to determine the mechanism of S4-related complications. The postoperative parameters of SLT and their impact on graft and overall survival were also evaluated.

RESULTS

Although two biliary leakages were noted (3.2%), no necrosis of S4 developed after LLSLD. S4-related complications were seen in 15 (28.3%) patients after SLT. Radiological volumetry of S4 and the ischemic area after SLT showed no significant difference between those with and without S4-related complications. There were no significant differences between the patients with and without S4-related complications regarding both overall and graft survival rates. Significant better overall and graft survival rates were observed in patients treated during the later period.

CONCLUSIONS

S4-related complications after SLT are totally independent of the S4 volume, and biliary leakage is inherently an actual mechanism. Adequate intervention with early identification leads to better graft and overall survival, which validates SLT as a treatment option.

Imaging of biliary complications in recipients of right-lobe living donor liver transplantation

Right-lobe living donor liver transplantation (RL-LDLT) is a common method devised in order to fulfill the demands of donor organ shortage in adult patients with end-stage liver diseases. However, biliary complications remain as the "Achilles' heel" of RL-LDLT, with wide variety of incidence among transplantation centers. Patients with biliary complications after RL-LDLT may have similar clinical presentations to those with other causes of graft dysfunction. Therefore, radiological evaluation plays a key role for differential diagnosis of such complications. In this article, we discuss the various methods of biliary reconstruction and imaging findings of common and uncommon biliary complications in recipients of RL-LDLT.

Targeting the Achilles' heel of adult living donor liver transplant: Corner-sparing sutures with mucosal eversion technique of biliary anastomosis

Biliary complications are regarded as the Achilles' heel of liver transplantation, especially for living donor liver transplantation (LDLT) due to smaller, multiple ducts and difficult ductal anatomy. Overall biliary complications reported in most series are between 10% and 30%. This study describes our modified technique of biliary anastomosis and its effects on incidence of biliary complications. This was a single-center retrospective study of 148 adult LDLT recipients between December 2011 and June 2014. Group 1 (n = 40) consisted of the first 40 patients for whom the standard technique of biliary anastomosis (minimal hilar dissection during donor duct division, high hilar division of the recipient bile duct, and preservation of the recipient duct periductal tissue) was used. Group 2 (n = 108) consisted of 108 patients for whom biliary anastomosis was done with the addition of corner-sparing sutures and mucosal eversion of the recipient duct to the standard technique. Primary outcome measures included biliary complications (biliary leaks and strictures). Biliary complications occurred in 7/40 patients in group 1 (17.5%) and in 4/108 patients in group 2 (3.7%). The technical factors mentioned above are aimed at preserving the blood supply of the donor and recipient ducts and hold the key for minimizing biliary complications in adult-to-adult LDLT.

Management of biliary complications after liver transplantation

Biliary complications (BC) currently represent a major source of morbidity after liver transplantation. Although refinements in surgical technique and medical therapy have had a positive influence on the reduction of postoperative morbidity, BC affect 5% to 25% of transplanted patients. Bile leak and anastomotic strictures represent the most common complications. Nowadays, a multidisciplinary approach is required to manage such complications in order to prevent liver failure and retransplantation.

Spectrum of biliary complications following live donor liver transplantation

Liver transplantation is the optimal treatment for many patients with advanced liver disease, including decompensated cirrhosis, hepatocellular carcinoma and acute liver failure. Organ shortage is the main determinant of death on the waiting list and hence living donor liver transplantation (LDLT) assumes importance. Biliary complications are the most common post operative morbidity after LDLT and occur due to anatomical and technical reasons. They include biliary leaks, strictures and cast formation and occur in the recipient as well as the donor. The types of biliary complications after LDLT along with their etiology, presenting features, diagnosis and endoscopic and surgical management are discussed.

Review of the surgical approach to prevent small-for-size syndrome in recipients after left lobe adult LDLT

Left lobe liver grafts increase the donor safety in adult-to-adult living-donor liver transplantation (ALDLT). However, the left lobe graft provides about 30-50 % of the required liver volume to adult recipients, which is insufficient to sustain their metabolic demands, which can lead to small-for-size syndrome (SFSS). Transient portal hypertension and microcirculatory hemodynamic derangement, apart from outflow obstruction, during the first week after reperfusion are the critical events associated with small-for-size graft transplantation. The incidence of SFSS in left lobe ALDLT can be decreased by increasing the left lobe graft volume by effective utilization of the caudate lobe with preserved vascular supply, by modulating the portal pressure with splenectomy or a porto-systemic shunt or by hepatic venous outflow reconstruction to prevent the development of venous congestion. In this review, we discuss the pathophysiology of SFSS and the various surgical strategies that can be performed to prevent SFSS in an effort to enhance the donor safety during living-donor liver transplantation.

Biliary complications after liver transplantation: old problems and new challenges

Due to a vulnerable blood supply of the bile ducts, biliary complications are a major source of morbidity after liver transplantation (LT). Manifestation is either seen at the anastomotic region or at multiple locations of the donor biliary system, termed as nonanastomotic biliary strictures. Major risk factors include old donor age, marginal grafts and prolonged ischemia time. Moreover, partial LT or living donor liver transplantation (LDLT) and donation after cardiac death (DCD) bear a markedly higher risk of biliary complications. Especially accumulation of several risk factors is critical and should be avoided. Prophylaxis is still a major issue; however no gold standard is established so far, since many risk factors cannot be influenced directly. The diagnostic workup is mostly started with noninvasive imaging studies namely MRI and MRCP, but direct cholangiography still remains the gold standard. Especially nonanastomotic strictures require a multidisciplinary treatment approach. The primary management of anastomotic strictures is mainly interventional. However, surgical revision is finally indicated in a significant number of cases. Using adequate treatment algorithms, a very high success rate can be achieved in anastomotic complications, but in nonanastomotic strictures a relevant number of graft failures are still inevitable.

Split liver transplantation using extended right grafts: the natural history of segment 4 and its impact on early postoperative outcomes

Split liver transplantation (SLT) using extended right grafts is associated with complications related to ischemia of hepatic segment 4 (S4), and these complications are associated with poor outcomes. We retrospectively analyzed 36 SLT recipients so that we could assess the association of radiological, biological, and clinical features with S4 ischemia. The overall survival rates were 84.2%, 84.2%, and 77.7% at 1, 3, and 5 years, respectively. The recipients were mostly male (24/36 or 67%) and had a median age of 52 years (range = 13-63 years), a median body mass index of 22.9 kg/m(2) (range = 17.3-29.8 kg/m(2) ), and a median graft-to-recipient weight ratio of 1.3% (range = 0.9%-1.9%). S4-related complications were diagnosed in 22% of the patients (8/36) with a median delay of 22 days (range = 10-30 days). Secondary arterial complications were seen in 3 of these patients and led to significantly decreased graft survival in comparison with the graft survival of patients without complications (50.0% versus 85.6%, P = 0.017). Patients developing S4-related complications had significantly elevated aspartate aminotransferase (AST) levels (>1000 IU/L) on postoperative day (POD) 1 and elevated gamma-glutamyl transpeptidase (GGT) levels (>300 IU/L) on PODs 7 and 10 (P < 0.05). These AST and GGT elevations conferred a significantly high risk of developing these complications (odds ratio = 42, 95% confidence interval = 4-475, P < 0.05). The ischemic volume of S4 was extremely variable (0%-95%) and did not correlate with S4-related complications. In conclusion, our results suggest that S4-related complications are risk factors for worse graft survival, and the development of these complications can be anticipated by the early identification of a specific biological profile and a routine radiological examination.

Biliary complications after living donor liver transplantation

Biliary complications occur more frequently after living donor liver transplantation (LDLT) versus deceased donor liver transplantation, and they remain the most common and intractable problems after LDLT. The anatomical limitations of multiple tiny bile ducts and the differential blood supplies of the graft ducts may be significant factors in the pathophysiological mechanisms of biliary complications in patients undergoing LDLT. A clear understanding of the biliary blood supply, the Glissonian sheath, and the hilar plate has contributed to new techniques for preparing bile ducts for anastomosis, and these techniques have resulted in a dramatic drop in the incidence of biliary complications. Most biliary complications after LDLT can be successfully treated with nonsurgical approaches, although the management of multiple biliary anastomoses and nonanastomotic strictures continues to be a challenge.

Biliary complications in living liver donors

With the increasing use of living donor liver transplantation (LDLT), the morbidity and mortality of the donors have thus become inevitable problems associated with this procedure. The most common postoperative complications among donors for LDLT involve the biliary tract. The incidence of biliary complications in donors tends to be about 5% based on recent publications. Anatomical variations in the biliary tract, higher predonation alkaline phosphatase levels, and intraoperative blood transfusions are also risk factors for biliary complications in the donors after donation. Donors with biliary complications often show unspecific symptoms and most of the biliary complications can be normally treated by nonsurgical methods. Interventional procedures such as percutaneous placement of a peritoneal drain, percutaneous/endoscopic biliary drainage, and combinations of balloon dilatation and/or stenting are effective in the treatment of bile leakage and biliary stricture. A clear understanding of the biliary anatomy of each donor and refined surgical techniques will help to minimize risk of biliary complications for living liver donors.

Auxiliary liver transplantation for acute liver failure in children

OBJECTIVE

The aim of this study is to present the largest experience of auxiliary liver transplantation for acute liver failure (ALF) in children over the past 19 years.

METHODS

Between 1990 and 2009, a total of 128 liver transplants were performed on children with ALF. Of these, 20 received auxiliary liver transplants (19 were cadaveric and 1 living graft). The recipient median age was 12 years (range: 1 -16). Indications for auxiliary partial orthotopic liver transplantation were seronegative non-A non-B hepatitis in 16 children, drug induced in 2, and 1 autoimmune hepatitis and 1 mushroom poisoning. The median waiting time for transplantation was 2 days (range: 1-9). After native liver partial hepatectomy, 20 grafts were implanted orthotopically and included 8 right lobes, 8 left lateral segments, 3 left lobes, and 1 whole liver. Regeneration of the native liver was assessed by radiologic, nuclear medicine imaging, and histology. Follow-up imaging and biopsies were performed at intervals of 3 to 6 months and yearly.

RESULTS

Patient survival was 85% at 1, 5, and 10 years. There were 3 deaths at a median of 9 days (range: 8-52) post-transplantation. There was 1 retransplant for chronic rejection 15 months post-transplantation. There were no biliary or vascular complications. Of 17 survivors, 14 (82%) have successfully regenerated their native liver and so far 11 children (65% of the survivors) have been withdrawn from immunosuppression at a median time of 23 months (range: 4-106) after transplantation.

CONCLUSION

Auxiliary partial orthotopic liver transplantation should be considered in children presenting with ALF who fulfill criteria for liver transplantation.