CPR (cardiopulmonary resuscitation) is an emergency procedure to get your heart beating again when it unexpectedly stops (cardiac arrest). When your heart stops beating it stops pumping blood around your body - starving your brain of oxygen. The longer your brain goes without oxygen, the greater the chance of brain damage and death. CPR can keep your blood pumping until professional medical help arrives.
This is a companion discussion topic for the original article at https://patient.info/news-and-features/the-importance-of-learning-cpr