Cardiopulmonary resuscitation (CPR) is an emergency procedure for manually preserving brain function until further measures to restore spontaneous blood circulation and breathing in a person who is in cardiac arrest. It is indicated in those who are unresponsive with no breathing or abnormal breathing, for example, agonal respirations (Source: Wikipedia).
In simple terms it is an act that can help save a life. CPR either through a combination of chest compressions and mouth-to-mouth resuscitation or through chest compressions only can help push blood to the brain to keep the person alive. CPR increases the person’s chances of survival if started soon after the heart has stopped beating. Without CPR , it only takes few minutes for the person to become brain dead due to a lack of oxygen.
CPR does not guarantee that the person will survive, but it does double or triple the chance of a person’s survival when administered.