This document discusses the differences between asystole, pulseless electrical activity (PEA), true PEA/electromechanical dissociation (EMD), and pseudo-PEA in cardiac arrest patients. While an algorithm may indicate the same treatment for asystole and PEA, they are clinically and therapeutically different conditions. The document recommends using central pulse palpation, EKG trace, end-tidal carbon dioxide, and point-of-care ultrasound to differentiate between these non-shockable rhythms and determine the appropriate treatment.