364 Feasibility Study of Emergency Department Resuscitative Endovascular Balloon Occlusion of the Aorta in Medical Cardiac Arrest

ABSTRACT

Study Objectives: Resuscitative endovascular balloon occlusion of the aorta (REBOA) is a hemorrhage control technique involving the intra-vascular occlusion of the thoracic aorta using a balloon catheter and may help to increase coronary and cerebral perfusion during out-of-hospital cardiac arrest (OHCA) by blocking blood flow to the lower body. Primary Objective: The primary objective of this study is to assess the feasibility of an emergency medicine (EM)-initiated multi-disciplinary protocol for REBOA in non-traumatic OHCA. Secondary Objectives: Secondary objectives are procedural outcomes (eg, attempts required for common femoral access), hemodynamic outcomes before and after aortic occlusion (end-tidal carbon dioxide, diastolic blood pressure), and rates of return of spontaneous circulation (ROSC) and survival to hospital discharge with a favorable neurologic outcome. Methods: This single-arm early feasibility study of REBOA initiated in the emergency department (ED) for OHCA uses an investigational device approval with a community exception from informed consent. Subjects under 80 years of age with witnessed OHCA and down time under 45 minutes are eligible. On arrival to the ED, an emergency physician obtains common femoral access using a 7Fr introducer sheath while the REBOA catheter is prepared and subsequently advanced by an interventional radiologist (IR). Results: Two patients were enrolled between January and February 2020, with a temporary pause in enrollment due to the COVID pandemic from March - August 2020. To our knowledge, this is the first trial of ED-initiated REBOA involving emergency physicians for non-traumatic OHCA (two similar recent reports exist in the anesthesia and critical care literature). Our initial patient was a 77-year-old man who presented in refractory ventricular fibrillation. The emergency physician placed the common femoral sheath on the first attempt using ultrasound guidance under chest compressions and the REBOA catheter was then advanced by the interventional radiologist. After inflation of the aortic balloon, investigators noted immediate improvements in mean arterial pressure (MAP) (37 to 50 mmHg) and end-tidal carbon dioxide (ETCO2) (35 to 50 mmHg), with transient non-sustained ROSC. The second patient, a 63-year-old man, underwent successful REBOA placement with similar improvements in MAP (22 to 50 mmHg) and ETCO2 (33 to 43 mmHg). Unfortunately, both patients were in refractory ventricular fibrillation and despite multiple defibrillation attempts and antiarrhythmics they did not survive to hospital admission. Conclusion: REBOA has been hypothesized to improve outcomes in OHCA by blocking blood flow to the lower body and redirecting it towards the heart and brain, improving the perfusion of these vital organs. In both cases, REBOA was temporally associated with improved hemodynamics during chest compressions with transient ROSC in one case. Performance of REBOA by a multi-disciplinary team for OHCA in the ED was feasible in these initial two cases. Future research will examine the feasibility of REBOA catheter advancement by the emergency physician and further quantify the hemodynamic effects associated with aortic occlusion. [Formula presented]