Most common cause of electromechanical dissociation:
Electromechanical dissociation (EMD) is also called as pulse electrical activity (PEA). In this condition pulses r are not palpable but heart shows some activity other than ventricular fibrillation and ventricular tachycardia.
The most common cause is hypovolemia. Other causes are hyperkalemia, hypocalcemia, acidosis, hypoxia, pulmonary embolism, pneumothorax, cardiac tamponade, overdosage of digitalis, calcium channel blockers and blockers.