This study seeks to establish hemodynamic threshold values that are able to discriminate between patients that achieve return of spontaneous circulation (survivors) and those that fail to do so (non-survivors). These cutoff values could act as targets for interventions during CPR (i.e. application of vasoactive drugs, use of mechanical compression devices, …) in further trials and may potentially influence clinical practice later on. Furthermore, reliable cutoff values could act as additional prognostic factors during CPR, enabling prehospital care providers to base their decisions to continue or terminate ongoing CPR efforts on a more solid basis.