Even if there is no examination and forgetting, it is definitely necessary to retrain the theory and operation of CPR at least once every five years in departments where CPR is not commonly used (that is, except emergency department and ICU). Because although the annual physical examination outline must include the contents of cardiopulmonary resuscitation, according to the cardiopulmonary resuscitation guidelines, the techniques of cardiopulmonary resuscitation are updated every five years, so major training work must be carried out at least every five years.