HPI 

60 y.o. male with a PMH of PVD s/p aorto-bifemoral bypass c/b aortoenteric fistula (duodenum-graft) s/p excision aorto-left uni fem with inline recon from aorta to L fem, COPD, HTN, prior DVT (negative duplex BLE 2 weeks ago) who p/w cardiac arrest and hypotension

• EMS report: unresponsive and pulseless → PEA arrest, 5 min CPR + epi → ROSC, intubated in the field
• Family: recent fatigue and somnolence/AMS

Physical Exam

• HR 126, BP 59/38, POX 97% on ETT
• MAE spontaneously
• Abdomen is distended, soft and there is a large hernia with well healed abd incisions

DDx: AAA leak vs. GIB [prior h/o aortoenteric fistula] vs. massive PE [prior h/o DVT but negative BLE Doppler US 2 weeks prior] vs. septic shock [dry gangrene of L great toe] vs. cardiogenic shock

Management:

• FAST negative for free fluid, no RV dilation, limited abdominal aorta exam
• 2 units of PRBC ordered (Hgb 8.2; 10 days ago 10.3)
• Crit care consult
• He then had several episodes of large volume maroon colored stool + > 1 L of maroon output via NG tube 
• Given pRBCs, FFP, Plts → massive transfusion protocol (Cooler of 5 units pRBCs + 5 units of plasma of uncrossmatched blood + 1 unit of platelets prepped for pickup every 15 minutes)
• BP improved slighly to obtain CTA
• Surgery consulted for aortoenteric fistula and taken to OR by vascular

Take home points:

• Aortoenteric fistula = an abnormal connection between the aorta and GI tract, usually because of erosion of prosthetic graft (e.g., prior AAA repair) into surrounding structures
• Pt may present with a self-limited "herald" bleed from above or below, which usually precedes a massive hemorrhagic event 
• Hemodynamically unstable patients + bleeding + known AAA → go directly to OR after initial resuscitation and antibiotics

References:

Ziebell CM, et al.Upper Gastrointestinal Bleeding. In: Tintinalli JE, Stapczynski J, Ma O, Yealy DM, Meckler GD, Cline DM. Tintinalli J.E., Stapczynski J, Ma O, Yealy D.M., Meckler G.D., Cline D.M. Eds. Judith E. Tintinalli, et al.eds. Tintinalli’s Emergency Medicine: A Comprehensive Study Guide, 8e New York, NY: McGraw-Hill; 2016. http://accessemergencymedicine.mhmedical.com/content.aspx?bookid=1658&se.... Accessed September 11, 2019.