May 1, 2021

Background: Head up (HUP) CPR is an emerging concept.  The theory behind HUP is it allows for venous blood to drain from the brain to the heart thereby decreasing intracranial pressure and lowering the arterial/venous pressure waves which concuss the brain with each compression.  Additionally, conventional CPR increases vascular pressure in both the venous and arterial sides of the heart simultaneously which in turn increases intrathoracic and intracranial pressure which can impede cerebral blood flow and compromise coronary circulation.  All of these theories were evaluated and confirmed in animal models with very limited human trials. In order for HUP to work however, we have to be able to effectively pump blood up to the brain which is not typically achieved with conventional CPR (C-CPR). Active Compression Decompression with Impedance Threshold Devices (ACD-ITD) are one way to improve C-CPR.  They can theoretically help by reducing intracranial pressure (ICP), reduce the potential for concussion with every compression, increase cerebral perfusion pressure (CerPP) and coronary perfusion pressure (CorPP). However, with any new approach, we should always temper enthusiasm, as the realities of implementing them may actually not be helpful, and maybe even harmful.