Warm ischemia may damage peribiliary vascular plexus during DCD liver transplantation

Biliary complications cause significant morbidity and mortality in liver transplantation. Warm ischemia can induce biliary duct injury. This study aimed to investigate the effects of warm ischemia on the peribiliary vascular plexus in rat liver transplantation. A total of 102 Sprague-Dawley rats were divided into three groups: sham-operation group, non-ischemic group, and ischemic group. Liver transplantation was performed in both the non-ischemic group and the ischemic group. The animals were sacrificed on day 1, 3, 7, and 14 to collect the blood and liver samples. Serum levels of bile duct obstruction, viz, alkaline phosphatase and gamma-glutamyl transpeptidase, as well as direct and indirect bilirubin were measured. Liver biopsy samples were examined with hematoxylin-eosin staining and transmission electron microscopy. The levels of enzymes and bilirubin were significantly higher in the ischemic group than the non-ischemic group and sham-operated animals (P<0.05), with return to normal levels in the ischemic group after two weeks. Morphological examination showed microthrombi and endothelial damage in the bile ducts and the peribiliary vascular plexus of the ischemic group. Warm ischemia/reperfusion injury can damage the endothelium of the peribiliary vascular plexus, which might compromise the bile duct microcirculation and lead to ischemic cholangiopathy after liver transplantation.