PEA/Asystole (ACLS): etiology
Emergency medicine   Wikipedia  
Infarction
Tension pneumothorax
Cardiac tamponade
Hypovolemia/Hypothermia/Hypo-,Hyperkalemia/Hypomagnesmia/Hypoxemia
Pulmonary embolism
Acidosis
Drug overdose

 Mnemonic:
ITCHPAD