INTRODUCTION: Rare complications of endoscopic retrograde cholangiopancreatography (ERCP) are duodenal perforation, necrotizing pancreatitis, systemic air embolism (AE), and septic cerebral infarction. We present a case of ERCP associated AE, bacteremia, and septic cerebral infarction in one patient that survived. CASE DESCRIPTION/METHODS: A 52-year-old female with a history of choledocholithiasis, ERCP lithotripsy and stent placement 1 month prior, presented for outpatient ERCP and underwent stent removal, duct dilation and removal of multiple stones. Immediately post procedure, she became unresponsive with supraventricular tachycardia and hypotension requiring ICU admission and intubation. A stat EKG showed diffuse ST elevations with near complete resolution on repeat EKG 20 minutes later. Additionally, a stat abdominal CT showed portal venous gas confirming the presence of an AE (Figure 1). However, troponins eventually rose to 17 ng/mL, thus heparin was started until NSTEMI could be ruled out. Empiric antibiotics were also started due to persistent hypotension and infectious workup ensued. Urgent cardiac catheterization showed non-occlusive disease, and heparin was stopped. Her blood cultures grew Enterobacter hormaechei, thought to have seeded during ERCP, and antibiotics were streamlined. Despite hemodynamic improvement, she had difficulty awakening from sedation and a subsequent brain MRI revealed bifrontal hemorrhagic emboli, likely septic due to involvement of various vascular territories and known ERCP-associated bacteremia. Furthermore, there was no pneumocephalus, ruling out cerebral AE, and no vegetation on transesophageal echo, ruling out endocarditis. DISCUSSION: AE may be confused with an anesthetic side effect or acute ischemic event. It should be considered with sudden clinical deterioration during or immediately after ERCP. The diagnosis is often made post-mortem, thus clinical suspicion is paramount and may be confirmed after visualizing air in the vena cava, portal vein, heart, or brain. Air can be absorbed rapidly thus diagnosis can be made on clinical suspicion alone. Air insufflation into the portal vein can occur during sphincterotomy and use of CO2 can minimize risk of AE. Anticoagulation is not indicated and treating NSTEMI may have allowed for hemorrhagic conversion of septic emboli, which are already prone to hemorrhage. Septic cerebral emboli from ERCP are exceedingly rare, with a handful of reported cases. Our case urges awareness of potential catastrophic sequela of ERCP.Figure 1.: Abdominal CT without contrast demonstrating the peripheral pattern of portal venous gas (arrows) as well as the central gas pattern of pneumobilia (ellipse).Figure 2.: Coronal abdominal CT demonstrating air in the portal venous system.