Hemodynamics, survival and neurological function with early versus delayed automated head-up CPR in a porcine model of prolonged cardiac arrest

To determine if controlled head and thorax elevation, active compression-decompression cardiopulmonary resuscitation (CPR), and an impedance threshold device combined, termed automated head-up positioning CPR (AHUP-CPR), should be initiated early, as a basic (BLS) intervention, or later, as an advanced (ALS) intervention, in a severe porcine model of cardiac arrest.