Cardiopulmonary resuscitation, commonly called CPR, combines rescue breathing (one person breathing into another person) and chest compression in a lifesaving procedure performed when a person has stopped breathing or a person's heart has stopped beating.
When performed quickly enough, CPR can save lives in such emergencies as loss of consciousness, heart attacks or heart "arrests," electric shock, drowning, excessive bleeding, drug overdose, and other conditions in which there is no breathing or no pulse. The purpose of CPR is to bring oxygen to the victim's lungs and to keep blood circulating so oxygen gets to every part of the body. When a person is deprived of oxygen, permanent brain damage can begin in as little as four minutes and death can follow only minutes later.
There are three physical symptoms that indicate a need for CPR to be performed immediately and for emergency medical support to be called: unconsciousness, not breathing, and no pulse detected.
Unconsciousness is when the victim seems to be asleep but has lost all awareness and is not able to respond to questions or to touch or gentle shaking. A sleeping person will usually respond to a loud noise, shouting, or gentle shaking. An unconscious person will not respond to noise or shaking. When unconscious, a person can not cough or clear the throat, which can block the windpipe and cause suffocation and death. People with a major illness or injury or who have had recent surgery are at risk for losing consciousness. If the person has fainted, which is brief unconsciousness, the cause may be dehydration (lack of body fluids), low blood pressure, or low blood sugar. This is a temporary condition. If the victim is known to have diabetes, a bit of fruit juice may revive the person once they have regained consciousness.
Just before a person loses consciousness, symptoms may include: