Intrathoracic Pressure Regulator During Continuous-Chest-Compression Advanced Cardiac Resuscitation Improves Vital Organ Perfusion Pressures in a Porcine Model of Cardiac Arrest

Background— A novel device, the intrathoracic pressure regulator (ITPR), combines an inspiratory impedance threshold device (ITD) with a vacuum source for the generation of controlled −10 mm Hg vacuum in the trachea during cardiopulmonary resuscitation (CPR) while allowing positive pressure ventilation. Compared with standard (STD) CPR, ITPR-CPR will enhance venous return, systemic arterial pressure, and vital organ perfusion in both porcine models of ventricular fibrillation and hypovolemic cardiac arrest. Methods and Results— In protocol 1, 20 pigs (weight, 30±0.5 kg) were randomized to STD-CPR or ITPR-CPR. After 8 minutes of untreated ventricular fibrillation, CPR was performed for 6 minutes at 100 compressions per minute and positive pressure ventilation (100% O2) with a compression-to-ventilation ratio of 15:2. In protocol 2, 6 animals were bled 50% of their blood volume. After 4 minutes of untreated ventricular fibrillation, interventions were performed for 2 minutes with STD-CPR and 2 minutes of IT...