Function

• Simply put, CPR, when performed properly, helps manually to keep some level of blood flow and breathing going on in a victim whose heart has suddenly stopped. A rescuer, either a bystander providing CPR, or a trained emergency medical service worker, can help maintain some level of life in someone who is dying.
  
  

Significance

• The body survives on blood and oxygen. In cases of sudden cardiac arrest, both processes stop. Rescuers using CPR compress the chest to artificially pump the heart and push the blood through the system. The chest should be compressed 1 1/2 inches to 2 inches deep. After 30 compressions, a rescuer should then provide the victim with two quick breaths, which deliver some oxygen to the victim.
  
  

Facts

• The American Heart Association estimates that 95% of the people who suffer from sudden cardiac arrest do not make it to the hospital alive. The organization also stresses that the immediate start of CPR by bystanders to such events can dramatically improve the survival rate.
  
  

History

• Some elements of CPR were developed over two centuries. However, CPR as we know it, along with the basic skills used today, began to emerge 50 years ago, according to the American Heart Association. The first guidelines were published in 1966. Now, classes are taught under the guidance of the AHA, the American Red Cross and the American Safety and Health Institute.
  
  

Considerations

• The AHA estimates only 27.4% of all sudden cardiac arrest victims get bystander CPR. It is better to do something than nothing in those situations, according to MayoClinic.com.