eP604 - A Rare Case of Rectosigmoid Blowout Following Superior Artery Embolization for Rectal Bleed

Purpose/Background: Rectal bleeding is a significant medical emergency, and when conventional therapies fail transcatheter superior rectal artery (SRA) embolization can be a life-saving intervention. Literature has supported the feasibility, efficacy and safety of SRA embolization for hemorrhoidal and variceal bleeding. Major complications, such as rectal ischemia and perforation are rare due to the relatively rich anastomotic vascular supply between branches of the inferior mesenteric and internal iliac arteries. There have been no previously reported major complications of intestinal ischemia following selective SRA embolization. We present a rare case of rectal ischemia, perforation with intra-peritoneal abscess following SRA embolization requiring laparotomy with washout and creation of end colostomy.Methods/Interventions: A 68-year-old man with a history of medical noncompliance, atrial fibrillation on Eliquis and alcohol abuse who had a prolonged hospitalization. He developed significant rectal bleeding requiring multiple blood transfusions and intensive care unit (ICU) admission. Initial computed tomography angiogram (CTA) abdomen/pelvis revealed active extravasation within the rectum with increased pooling on delayed imaging. He underwent IR mesenteric angiogram which showed active extravasation from the SRA controlled with coil embolization. He had recurrence of rectal bleeding several days later requiring multiple additional blood transfusions. Repeat CTA abdomen/pelvis with oral contrast showed continued active bleeding within the sigmoid colon without evidence of oral contrast extravasation. He underwent subsequent IR mesenteric angiogram which showed active extravasation from multiple collateral branches supplying the sigmoid colon with repeat embolization. He was still having persistent bleeding thus he underwent sigmoidoscopy which showed significant rectal ischemia. An urgent laparotomy was performed which revealed a large abscess cavity abutting the anterior abdominal wall. The rectosigmoid junction was completely blown out in an open book fashion as evidenced by mucosal islands which contributed to the posterior wall of the abscess cavity. The blown out end of the sigmoid colon was easily identified and controlled for end colostomy creation. The open rectal stump was closed with 0 non-absorbable running V-lock suture and an end sigmoid colostomy was created.Results/Outcomes: Postoperatively, the patient’s clinical condition gradually improved. He was managed in the ICU with broad-spectrum antibiotics, enteral nutrition and supportive care. Patient stabilized with predictable colostomy output and was discharged to a long term acute care hospital.Conclusion/

Discussion: While majority of studies have justified the efficacy and safety of SRA selective embolization to minimize the risk of bowel ischemia, it is, however, a potential complication that must be considered. Embolization of more than 3 vasa recta can induce ischemic bowel, however the ischemia is usually self-limiting and silent. This patient had two consecutive IR angiograms with embolization; this coupled with poor vasculature likely contributed to the ischemic complications requiring operative intervention. This case demonstrates the importance of appropriate patient selection for selective SRA embolization and minimizing subsequent consecutive arterial embolization as this increases the risk of rectal ischemia."Figure 1. Selective mesenteric angiogram with embolization of superior rectal artery

a. Active extravasation of the superior rectal artery (arrow)
b. Post-coil embolization with resolution of extravasation
Figure 2. Flexible sigmoidoscopy

a. Sigmoid colon with ischemic changes
b. Rectosigmoid junction with mucosal islands, the area of perforation as correlated with intra-operative findings
Figure 3. Computed tomography angiogram of the abdomen and pelvis

Large anterior abscess cavity from rectosigmoid junction perforation (white arrow) with active extravasation (red arrow)"