Arterio-Duodenal Fistula: A Rare Complication of Laparoscopic Choledochal Cyst Excision.

Choledochal cysts (CDC) are rare biliary tract anomalies characterized by congenital dilatation of the extrahepatic and/or intrahepatic bile ducts. CDC excision with hepatico-enterostomy is the preferred surgery in modern era. Perioperative blood loss in a case of laparoscopic choledochal cyst excision (LCCE) is usually minimal and managed by conservative treatment such as blood transfusion and correction of coagulation factors. Massive hemorrhage in LCCE is rare and reported intraoperatively or within the first 3 postoperative days. Hereby, we present an unusual case of arterio-duodenal fistula, post LCCE presenting as delayed massive upper gastrointestinal bleeding in a male child and its successful endovascular management. Copyright:

INTRODUCTION

Choledochal cysts (CDC) are rare biliary tract anomalies characterized by congenital dilatation of the extrahepatic and/or intrahepatic bile ducts.[1] Frequently diagnosed in Asian children with most cases diagnosed in under 5 years of age, they can be seen in adults too.

CDC predisposes to recurrent cholangitis, pancreatitis, biliary obstruction by stone formation or sludge, biliary cirrhosis and portal hypertension, as well as bile duct malignancy, which form the rationale for surgical intervention.[2]

Cyst excision with hepatico-enterostomy (HE) is the preferred surgery in modern times with an increase in laparoscopic techniques, as the potential for malignancy forms a strong basis for en bloc cyst excision.

Generally considered a safe surgery, laparoscopic choledochal cyst excision (LCCE) with HE can rarely present with early or delayed hemorrhage. Hereby, we report an unusual case of delayed postoperative upper gastrointestinal (GI) bleeding in an 8-year-old male child with elusive imaging findings and its successful endovascular management. We hope this case report also sheds light on the caveats to consider the catheter angiogram of a bleeding patient even when no evidence of frank extravasation or pseudoaneurysm is found on computed tomography (CT) angiography.

CASE REPORT

An 8-year-old boy with Type-IVa CDC underwent LCCE with hepatico-duodenostomy (HD). The surgery was uneventful, and the patient was discharged in stable condition. He readmitted 1 week after surgery with one episode of a was small amount of hematemesis which was managed conservatively and discharged.

He again presented in emergency 2 weeks after surgery with three episodes of hematemesis; each time, the patient vomited about 50–100 ml of fresh blood. Coagulation parameters were normal. Upper GI endoscopy was suboptimal due to the presence of blood in the stomach. During the hospital stay, he had an episode of massive hematemesis (approx. 300–400 ml) requiring two units of blood transfusion and inotrope support. After hemodynamic stabilization, CT angiography with abdomen was performed which showed luminal contour irregularities in the proximal right hepatic artery (RHA) and its branch [Figure 1a]. In addition, the proximal part of RHA is seen in the posterior wall of HD anastomosis [Figure 1b].

Figure 1

Contrast-enhanced arterial-phase computed tomography (a) in the coronal plane showing significant luminal narrowing of the right hepatic artery (black arrow) with inferior tenting. Axial computed tomography (b) showing proximal right hepatic artery lying in the posterior wall of hepatico-duodenostomy anastomosis (white arrow). Right hepatic artery selective angiogram (c) showing the luminal narrowing of right hepatic artery with active contrast extravasation (dashed arrow) into the lumen of the duodenum. Post coil (dashed black arrow) embolization (d) no extravasation and filling of the distal right hepatic artery through collateral branches (double black arrow)

In view of suspicious RHA morphology on CT angiography, digital subtraction angiography (DSA) was of abdomen performed. The patient had another episode of upper GI bleed on the table during the procedure (seen as fresh blood draining through the nasogastric tube into the collecting bag). The selective angiogram of the celiac axis at that time revealed focal inferior wall defect in RHA with definite extravasation of contrast [Figure 1c]. Embolization was performed using microcoils across the neck of extravasation with occlusion of proximal RHA. Check angiogram from hepatic artery proper showed no contrast extravasation with the collaterals filling distal part of the RHA [Figure 1d]. No retrograde filling of the extravasated segment of RHA was seen.

The patient had an uneventful postprocedural stay and was discharged on the 5th postprocedure day. He had no further episodes of hematemesis or melena, and his liver functions were normal during his 3-month follow-up.

DISCUSSION

CDC excision and HE forms the mainstay of treatment for CDC at present. The incidence of complications is low, lower so in children, and biliary complications form the major chunk of it.[3]

The hemorrhagic complication of LCCE is rare and described intraoperatively in the early postoperative period. Wang et al. reported one case of LCCE in a 12-year-old child, with conversion to an open procedure because of bleeding.[4] Diao et al. reported one case of massive bleeding presented with hemorrhagic shock at postoperative day 3 requiring redo surgery.[56] The various causes of intraoperative hemorrhage include trocar injuries, bleeding during cyst separation, direct vascular injury, and abnormal coagulation.[5]

Careful preoperative evaluation for anatomical variation of RHA is important to avoid accidental vascular injury. Normally, RHA courses posterior to CHD. However, in the case of aberrant RHA, it usually courses anterior to CHD. Replaced/aberrant RHA is responsible for 30% of cases of biliary re-obstruction after primary hepaticojejunostomy.[6] Hence, transposition of RHA posterior to CHD was suggested during surgery in normal anatomical position.[6]

Cyst separation is difficult in case of dense adhesion, which is seen with increased patient age due to chronic inflammation and bigger cyst size.[4] Since type IV CDC usually presents late in comparison to type I CDC, it is associated with more adhesion and hence surgical separation is difficult.[2]

In addition, hepatico-enteral anastomosis is technically difficult as the posterior wall of CHD is not under direct vision and may lead to accidental vascular injury.

Hence, various measures were suggested during the dissection of CHD from anterior or posterior placed RHA and posterior anastomosis of CHD with bowel loop. These include suspending and pulling the cyst with sutures, gradual dissection to separate the anterior wall of CHD from the replaced RHA or posterior wall of CHD from the normal RHA.[5] During posterior wall anastomosis, suspend the anterior wall of the CHD to expose the posterior wall.[5] Furthermore, the intestinal wall is opened more anteriorly to visualize the posterior wall more clearly during suturing.[4]

In our case, the age of the patient was 8 years and the diagnosis was Type IV CDC, which is associated with increased risk of complication due to more adhesion. On a retrospective review of the operative image, the RHA was seen in close proximity to the posterior wall of CHD. During the intracorporeal suturing of the posterior wall of the CHD with the duodenum, suture bites may have accidentally incorporated the wall of the RHA and artery exposed to duodenal contents including bile. With arterial pulsation, this tearing of arterial wall further aggravated. This led to the formation of arterio-duodenal fistula and delayed massive hemetemesis. This was explained by the inferior tilt and luminal narrowing of RHA in CT angiography and DSA [Figure 1a and c]. In addition, another supporting point was the absence of peritoneal bleeding or collection, as RHA was bleeding directly into the duodenal lumen.

The active leak from RHA into duodenum was seen during DSA and embolized using microcoils across the neck. Although the liver has dual blood supply from portal vein as well as hepatic artery with majority from the portal vein, the blood supply to intrahepatic bile ducts is from the hepatic artery.[7] Hence, complete hepatic artery embolization may lead to ischemia of the biliary system and stricture formation. This complication is seen commonly with distal embolization using permanent embolizing agents such as polyvinyl alcohol particles or N-butyl cyanoacrylate (glue). Proximal embolization using metallic coils or vascular plugs is similar to surgical proximal ligation and associated with less complication as distal branches recruit through collateral channels.

In our case, we used proximal embolization using microcoils bridging the neck of the fistula to stop the active hemorrhage. In post embolization run distal branches of RHA were filling through the collateral channels from left hepatic artery branches. In addition, embolization bridging neck prevents retrograde filling of fistula.

CONCLUSION

Arterio-duodenal fistula following CDC excision can present with delayed massive hemorrhage. Complication rate during CDC excision is more with increasing age, Type IV CDC, and aberrant course of RHA. Demonstration of RHA abnormality with embolization is a minimally invasive technique to avoid redo surgery.

Declaration of patient consent

The authors certify that they have obtained all appropriate patient consent forms. In the form, the patient has given his consent for his images and other clinical information to be reported in the journal. The patient understand that his name and initial will not be published, and due efforts will be made to conceal his identity, but anonymity cannot be guaranteed.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.