Abstract 201: Resuscitation And Hemodynamic Impact Of Aortic Balloon Occlusion And Percutaneous Left Ventricular Assist Device In A Swine Model Of Cardiac Arrest

Abstract

Introduction: Invasive mechanical support by percutaneous left ventricular assist device (pL-VAD) and percutaneous balloon occlusion of the aorta (pAO) during CPR have recently emerged as feasible resuscitation strategies for refractory cardiac arrest. It is unknown if combining pL-VAD and pAO has additive or synergist benefits during CPR. Hypothesis: Combined pAO and pL-VAD during CPR will significantly enhance coronary and cerebral perfusion pressure (CoPP, CePP), return of spontaneous heartbeat (ROSHB) rate, and post-ROSHB cardiac function compared to either therapy alone after prolonged cardiac arrest in a swine model. Methods: Nineteen swine 52 (3.9) kg; (9 male) were utilized. A pL-VAD (Impella CP®) and a balloon catheter were inserted through the femoral arteries under general anesthesia. Ventricular fibrillation was induced and left untreated for 8 minutes followed by 16 minutes of mechanical CPR (mCPR). Animals were randomized to 3 treatment groups A) pL-VAD (n=6), B) pL-VAD+pAO (n=6), and C) pAO (n=7). Treatment was initiated 24 minutes after arrest. mCPR was continued during treatment. Defibrillation was attempted 3 times starting at minute 28 and then every 4 minutes. Hemodynamics, cardiac function, and blood gases were monitored for 4 hours after ROSHB. Results: Following the intervention, CoPP for Group B increased by a mean (SD) of 26 (15) mmHg which is significantly different from both groups A and C, 3.6 (12) and 7.5 (6.3) mmHg ( p =0.007). CePP increased by 2 (11.5), 18.5 (18.6), and 8.3 (6.8) mmHg for groups A, B, and C with no significant differences ( p =0.06). The rate of ROSHB was 67% (4 of 6), 83% (5 of 6), and 100% (7 of 7) for groups A, B, and C ( p >0.05). All groups exhibited similar levels of post-ROSHB recovery including blood pressure, venous oxygen saturation, cardiac output, ejection fraction, and lactate clearance. Total ionotropic and vasopressor support (epinephrine and norepinephrine) was 56 (25), 50 (5), and 81 (90) mcg/Kg in groups A, B, and C ( p =0.66). Conclusion: Combined pAO and pL-VAD resulted in greater improvement of CPR hemodynamics compared to either intervention alone in this model of prolonged cardiac arrest. However, it remains unclear if this translates into better recovery of cardiovascular and neurological function.