Establishment of an animal model of ischemic type intrahepatic biliary lesion in rabbits

AIM:To explore a method to establish an animal model of ischemic type intrahepatic biliary lesion in rabbits. METHODS:Forty Japanese white rabbits of clean grade were divided randomly into four groups(10 rabbits per group)including sham operation(SO) group,and artery-bile obstruction(ABO)-1 h group, ABO-2 h group and ABO-3 h group.All the rabbits in this study underwent the same initial surgical procedure in which the liver was prepared as for graft removal during liver transplantation.Subsequently in the SO group,no additional vascular intervention was performed,while in groups ABO-1 h,ABO-2 h and ABO-3 h,the animals underwent combined clamping of the hepatic artery and common bile duct with microvascular clips for 1,2 and 3 h,respectively.After the scheduled occlusion time,the clip was removed to recover blood supply.The animals were killed 4 wk after operation.The survival rate,liver function, cholangiography and histopathological manifestation of the rabbits in each group were observed. RESULTS:The survival rate was 100%in groups SO,ABO-1 h and ABO-2 h,while it was 60%in group ABO-3 h.At each observation time,the change degree of the indexes of liver function was proportional to the clamping time(ABO-3 h>ABO-2 h>ABO-1 h> SO,P<0.05).Cholangiographical and histopathologic manifestations both showed that intrahepatic biliary lesion aggravated proportionally with the increase of the clamping time. CONCLUSION:An animal model of ischemic type intrahepatic biliary lesion in rabbits is successfully established,which may provide a reliable technique for basic and clinical research into the etiology, development and prophylaxis of ischemic type intrahepatic biliary lesion after liver transplantation.

Machine perfusion and the prevention of ischemic type biliary lesions following liver transplant:What is the evidence?

The widespread uptake of different machine perfusion(MP)strategies for liver transplant has been driven by an effort to minimize graft injury.Damage to the cholangiocytes during the liver donation,preservation,or early posttransplant period may result in stricturing of the biliary tree and inadequate biliary drainage.This problem continues to trouble clinicians,and may have catastrophic consequences for the graft and patient.Ischemic injury,as a result of compromised hepatic artery flow,is a well-known cause of biliary strictures,sepsis,and graft failure.However,very similar lesions can appear with a patent hepatic artery and these are known as ischemic type biliary lesions(ITBL)that are attributed to microcirculatory dysfunction rather than main hepatic arterial compromise.Both the warm and cold ischemic period duration appear to influence the onset of ITBL.All of the commonly used MP techniques deliver oxygen to the graft cells,and therefore may minimize the cholangiocyte injury and subsequently reduce the incidence of ITBL.As clinical experience and published evidence grows for these modalities,the impact they have on ITBL rates is important to consider.In this review,the evidence for the three commonly used MP strategies(abdominal normothermic regional perfusion[A-NRP],hypothermic oxygenated perfusion[HOPE],and normothermic machine perfusion[NMP])for ITBL prevention has been critically reviewed.Inconsistencies with ITBL definitions used in trials,coupled with variations in techniques of MP,make interpretation challenging.Overall,the evidence suggests that both HOPE and A-NRP prevent ITBL in donated after circulatory death grafts compared to cold storage.The evidence for ITBL prevention in donor after brain death grafts with any MP technique is weak.

Liver biochemistry profile,significance and endoscopic management of biliary tract complications post orthotopic liver transplantation

AIM： To correlate the significance of liver biochemical tests in diagnosing post orthotopic liver transplantation （OLT） biliary complications and to study their profile before and after endoscopic therapy.METHODS： Patients who developed biliary complications were analysed in detail for the clinical information, laboratory tests, treatment offered, response to it, follow up and outcomes. The profile of liver enzymes was determined. The safety, efficacy and outcomes of endoscopic retrograde cholangiography （ERC） were also analysed. RESULTS： 40 patients required ERC for 70 biliary complications. GGT was found to be 〉 3 times （388.1 ± 70.9 U/mL vs 168.5 4± 34.2 U/L, P = 0.007） and SAP 〉 2 times （345.1 ± 59.1 U/L vs 152.7 ± 21.4 U/L, P = 0.003） the immediate post OLT values. Most frequent complication was isolated anastomotic res in 28 （40%）. Sustained success was achieved in 26 （81%） patients. CONCLUSION： Biliary complications still remain an important problem post OLT. SAP and GGT can be used as early, non-invasive markers for diagnosis and also to assess the adequacy of therapy. Endoscopic management is usually effective in treating the majority of these biliary complications.

Complex liver retransplantation to treat graft loss due to long-term biliary tract complication after liver transplantation: A case report

BACKGROUND Loss of graft function after liver transplantation(LT) inevitably requires liver retransplant. Retransplantation of the liver(Re LT) remains controversial because of inferior outcomes compared with the primary orthotopic LT(OLT).Meanwhile, if accompanied by vascular complications such as arterial and portal vein(PV) stenosis or thrombosis, it will increase difficulties of surgery. We hereby introduce our center’s experience in Re LT through a complicated case of ReLT.CASE SUMMARY We report a patient who suffered from hepatitis B-associated cirrhosis and underwent LT in December 2012. Early postoperative recovery was uneventful.Four months after LT, the patient’s bilirubin increased significantly and he was diagnosed with an ischemic-type biliary lesion caused by hepatic artery occlusion. The patient underwent percutaneous transhepatic cholangial drainage and repeatedly replaced intrahepatic biliary drainage tube regularly for 5 years.The patient developed progressive deterioration of liver function and underwent liver re-transplant in January 2019. The operation was performed in a classic OLT manner without venous bypass. Both the hepatic artery and PV were occluded and could not be used for anastomosis. The donor PV was anastomosed with the recipient’s left renal vein. The donor hepatic artery was connected to the recipient’s abdominal aorta. The bile duct reconstruction was performed in an end-to-end manner. The postoperative process was very uneventful and the patient was discharged 1 mo after retransplantation.CONCLUSION With the development of surgical techniques, portal thrombosis and arterial occlusion are no longer contraindications for ReLT.