CPR stands for cardiopulmonary resuscitation. It is an emergency lifesaving procedure that is done when someone's breathing or heartbeat has stopped. This may happen after an electric shock, heart attack, or drowning.CPR combines rescue breathing and chest compressions.Rescue breathing provides oxygen to the person's lungs.Chest compressions keep oxygen-rich blood flowing until the heartbeat and breathing can be restored.Permanent brain damage or death can occur within minutes if blood flow stops. Therefore, it is very important that blood flow and breathing be continued until trained medical help arrives. Emergency (911) operators can guide you through the process.CPR techniques vary slightly depending on the age or size of the patient, including different techniques for adults and children 9 years and older, children 1 through 8 years old, and infants.