SESSION TITLE: Medical Student/Resident Critical Care Posters SESSION TYPE: Med Student/Res Case Rep Postr PRESENTED ON: October 18-21, 2020 INTRODUCTION: Aortoesophageal fistulas (AEFs) are a rare and deadly cause of upper gastrointestinal bleeds. Prior repair of the thoracic aorta, primary aortic aneurysms, foreign body ingestion and thoracic cancer account for more than 90% of AEFs. Here we present the case of a patient developing AEF after a diagnostic esophagogastroduodenoscopy (EGD). CASE PRESENTATION: A 72-year-old male smoker with a history lung cancer status post right lobectomy presented with months of progressive solid dysphagia. In the past months he underwent two EGDs with balloon dilation of esophageal strictures, of which the most recent one was complicated by a distal esophageal perforation requiring an esophageal stent. Weeks after stent removal his dysphagia returned, prompting a repeat EGD to obtain biopsies of his stricture [Figure 1A-B]. The post-operative course was complicated by a small episode of hematemesis, for which the patient was offered admission for observation but declined. After eating his first meal at home, the patient had a second episode of hematemesis which prompted him to present to the emergency department. On admission, the patient was noted to have hematemesis necessitating a rapid response activation. He underwent emergent endotracheal intubation for airway protection and was started on pantoprazole and octreotide infusions. A massive transfusion protocol was initiated, and the patient was transferred to the intensive care unit where he was started on multiple vasopressors for his hypovolemic shock. A stat computed tomography angiogram (CTA) of the chest was suspicious for an underlying aorto-esophageal fistula [Figure 2A-C]. Thoracic surgery was consulted and given the patient’s age and complexity of the procedure; he was deemed a poor surgical candidate. Ultimately the patient’s family decided to pursue comfort care and the patient passed shortly thereafter. DISCUSSION: The presentation of AEF is characterized by a triad of midthoracic pain, sentinel arterial hemorrhage, and massive hemorrhage after a symptom-free interval. While initial clot formation tamponades the fistula, GI contents rapidly weaken this clot. Evaluation for AEF should done with a CTA-Chest as it has been found to be more sensitive than EGD. Initial therapy should focus on achieving hemodynamic stability via thoracic endovascular aneurysm repair or aortic graft replacement. AEF outcomes are improved when the esophageal pathology can be addressed with esophagectomy, stenting, or fistula repair, and with use of post-operative broad-spectrum antibiotics. Prompt surgical intervention increases one-year survival up to 50%. CONCLUSIONS: AEF should be included in the differential of hematemesis after instrumentation for an EGD. Limited time exists between the herald bleed and massive hemorrhage to confirm the diagnosis and plan for a surgical approach. CTA-Chest should be obtained first, followed by an EGD when imaging is inconclusive. Reference #1: Takeno S, Ishii H, Nanashima A, Nakamura K. Aortoesophageal fistula: review of trends in the last decade. Surg Today. December 2019:1-9. Reference #2: Uittenbogaart M, Sosef MN, van Bastelaar J. Sentinel bleeding as a sign of gastroaortic fistula formation after oesophageal surgery. Case Rep Surg. 2014;2014:614312. Reference #3: Vu QDM, Menias CO, Bhalla S, Peterson C, Wang LL, Balfe DM. Aortoenteric fistulas: CT features and potential mimics. Radiographics. 2009;29(1):197-209. DISCLOSURES: No relevant relationships by Hareen Chela, source=Web Response No relevant relationships by Ethan Karle, source=Web Response No relevant relationships by Adam Letvin, source=Web Response No relevant relationships by Tarang Patel, source=Web Response No relevant relationships by Shyam Shankar, source=Web Response