Biliary bleeding is a condition reported by Sandblom as hemobilia . Hemorrhage occurs in the bile duct, and blood flows from the Vater papilla into the gastrointestinal tract, causing hematemesis and melena. In addition, obstruction of the bile duct can cause obstructive jaundice, cholangitis, and pancreatitis due to impaired bile excretion. (a) Severe right upper quadrant pain, (b) hematemesis and/or melena, and (c) elevated bilirubin are known as the three signs of hemobilia, as reported by Grove . Furthermore, Green et al.  reported that among 222 cases, the causes of hemobilia were iatrogenic (65%), inflammation (13%), tumor (7%), trauma (6%), and others (9%). To investigate the cause of hemobilia after LC, a PubMed search was conducted. After searching for keywords such as “Hemobilia,” “Postoperative,” and “Laparoscopic cholecystectomy,” 16 case reports (29 cases) were found [4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19] (Table 2). In these reports, the causes of hemobilia after LC was pseudoaneurysms of the hepatic artery or cystic artery stump. The most common treatment for hemobilia caused by pseudoaneurysms was embolization (23 cases), followed by operation (5 cases). In this case, diagnosis of hemobilia was possible by non-contrast and contrast CT, but identification of the cause artery was difficult. On the other hand, angiographic examination selective for the cystic artery branching from the middle hepatic artery revealed a micro-pseudoaneurysm, and embolization was performed. Angiographic examination is useful for identifying and treating the causative artery and needs to perform aggressively.
In examining the causes of micro-pseudoaneurysm formation and postoperative hemobilia, in this case, the following two points were considered: (a) the bifurcation of the hepatic artery and the cystic artery and (b) the timing of resumption of the direct Xa inhibitor.
Michels reported the bifurcation of the hepatic artery and the cystic artery. The hepatic artery’s bifurcation had been classified into 10 types . In addition, there are variations in bifurcation of the cystic artery. Typically, the cystic artery is single. The double cystic arteries and the superficial and deep branches of the cystic artery which had separate origin are observed in 25% . Andall presented the anatomical variations of cystic artery in literature review of over 9800 cases. That review has noted that in 8.9% (range 0.0–30.2 %) of cases, there were multiple cystic arteries present . The cystic artery, in this case, had one branch each from the right hepatic artery and the middle hepatic artery. Moreover, in this operation, the cystic artery bifurcated from the right hepatic artery was identified and processed intraoperatively, but the cystic artery bifurcated from the middle hepatic artery was not recognized preoperatively, and intraoperative identification was not possible. As a result of the untreated cystic artery branching from the middle hepatic artery, it is presumed that a micro-pseudoaneurysm of the cystic artery was formed. It is necessary to examine CT image findings in detail and to perform surgery with anatomical variation in mind.
There is no unified guideline for when to resume direct Xa inhibitors after surgery. According to the package insert of the direct Xa inhibitor, in the case of venous thromboembolism in patients undergoing lower limb orthopedic surgery, the first administration should be performed 12 h after surgery and after confirming that there is no bleeding from surgical wounds. In this case, the timing of reinstatement was examined according to this description. Due to a history of right lower limb artery thrombotic occlusion, the postoperative withdrawal period of the direct Xa inhibitor was as short as possible. Since there was no bleeding from the wound, we concluded that there was no risk of post-bleeding. When the administration of the direct Xa inhibitor was resumed on the 2POD, hemobilia occurred on the 3POD. The postoperative course suggests that the resumption of oral administration of the direct Xa inhibitor was one of the causes of hemobilia.