Etiology Of Non-surgical Technical Biliary Complications After Liver Transplantation

Objective:With the continuous advancement of liver transplantation(LT)technology and the replacement of immunosuppressive agents,LT has become the main management method for end-stage liver diseases.However,the non-surgical biliary tract complications,also known as ischemia-type biliary lesions(ITBL),are the main type of postoperative biliary complications.This complication is difficult to treat and has a poor prognosis,often requiring liver retransplantation.However,the pathogenesis of ITBL is still unclear,it may be related to warm ischemia time,cold ischemia time,relative warm ischemia time,biliary infection and bile composition.In addition,because the liver grafts itself has different energy reserves,the tolerance to ischemia and injury is also different,which suggests that ITBL can be predicted by studying the tissue damage and energy reserve of the donor liver.The purpose of this study was to prospectively analyze the warm ischemia time,cold ischemia time,relative warm ischemia time,light microscopy and electron microscopy of donor liver tissue,liver donor energy reserve,biliary tract infection and the bile acid metabolism within 2 weeks after liver transplantation,in order to identify factors that have strong predictive implications for ITBL.Methods:1 Object of study: Those 150 patients who underwent orthotopic liver transplantation and met the inclusion criteria at the First Central Hospital of Tianjin from March 1,2014 to August 31,2015.2 research content:(1)Record the sex,age,cold ischemia time,warm ischemia time and relative warm ischemia time of the donor before surgery;(2)The liver tissue samples were taken before the opening of the portal vein,before the opening of the hepatic artery and 1 h after the opening of the hepatic artery.The specimens of the donor liver tissue were divided into three parts in each period: the first part of the liver tissue was examined by light microscopy;The second part of the liver tissue was examined by electron microscopy;the third part of the liver tissue was tested for ATP,ADP and AMP;(3)Collect bile of liver transplant recipient 1 day,3 days,7 days and 14 days after surgery,and measure bile acid;(4)Observe the biliary tract infection of liver transplant recipient after liver transplantation.3 Clinical grouping: All patients were followed up for 3 years.After removing the dead cases,all patients were divided into ITBL group and NITBL group according to cholangiography results.4 Data processing: All measured results were grouped according to whether ITBL occurred or not,and the normality test was performed.The results of bile acid and electron microscopy were in accordance with the normal distribution.The t-test was used to perform the bile acid subgroups in the ITBL group and the NITBL group;the results ATP,ADP and AMP did not conform to the normal distribution,and the nonparametric test was used to compare the two groups.P<0.05 was statistically significant.then organize and analyze the results and draw conclusions.Results:1 Eventually 142 were actually followed up,according to the results of cholangiography,a total of 30 cases had happened ITBL within first three years after surgery,and the incidence of ITBL was 21.13%.2 There was no significant difference in gender between the ITBL group and the NITBL group(P=0.99).3 The ages of ITBL group and NITBL group were statistically different(P=0.044),and younger patients were more likely to have ITBL after liver transplantation.4 The ITBL group had a longer cold ischemia time than the NITBL group,and there was a significant difference between the two groups(P<0.001).5 The ITBL group had longer warm ischemia and relative warm ischemia time than the NITBL group,but there was no significant difference between the two groups(P=0.078;P=0.59).6 There was no statistical difference in the results of light microscopy between the ITBL group and the NITBL group.7 Electron microscopy observation of ultrastructure of donor liver,including capillary patency,biliary microvilli,mitochondrial swelling,mitochondrial sputum clarity and hepatic sinus patency.The results show that the above five aspects are closely related to the occurrence of ITBL.8 There were no significant differences in ATP,ADP and AMP levels between the ITBL group and the NITBL group(P>0.05).9 Comparison of free bile acid results: There was a statistically significant difference on the 1st after operation in CDCA between the ITBL group and the NITBL group.Another free bile acid results were no statistically significant difference between the ITBL group and the NITBL group(P>0.05).10 Comparison of bound bile acid results: the TLCA content in ITBL group and NITBL group was statistically significant on the 3rd,7th and 14 th d ay after operation(P<0.05).The GCDCA content between the groups was different on the 3rd and 14 th day after operation(P<0.05).The GDCA content between the two groups was different on the 3rd and 7th day after operation(P<0.05).GCA and TDCA had differences(P<0.05)only on the 7th day after surgery and 14 th day after surgery.Another bound bile acid results were no statistically significant difference between the ITBL group and the NITBL group(P>0.05).11 The positive incidence of bile culture in ITBL group was 33.33%,mainly Gram-negative bacilli;the positive rate of bile culture in non-ITBL group was 14.29%,mainly Gram-positive cocci.The rate of bile bacterial infection in the ITBL group was higher than that in the NITBL group,and there was a statistical difference(P=0.037).Conclusions:1 The incidence of ITBL is high after liver transplantation.2 Recipient age,cold ischemic time of donor liver,ultrastructure of donor liver(degree of biliary tract patency,number of biliary microvilli,de gree of mitochondrial swelling,degree of mitochondrial sputum clarity and degree of hepatic sinus patency),Partial bile acid content early postoperative liver transplantation and recipient bile bacterial infection are risk factors for ITBL after liver transplantation.3 Gender,warm ischemia time and relative warm ischemia time,light microscopy results of donor liver tissue,ATP,ADP and AMP levels in donor liver tissues were not significantly correlated with ITBL after liver transplantation.