How to Perform CPR on an Adult. A stopped heart deprives the brain of precious oxygen. Do CPR - short for "cardiopulmonary resuscitation" - to help prolong life while you wait for professional medical assistance.
Determine if the surrounding scene is safe (see "How to Maximize the Safety of an Emergency Scene").
Tell someone nearby to call 9-1-1, if not in a wilderness setting.
Determine if the injured person is breathing (see "How to Check Airway, Breathing and Circulation").
Position the injured person on his or her back, being extremely careful not to move or twist the head, neck or spine. If several rescuers are present, use their assistance to minimize this danger (For a related technique, see "How to Logroll an Injured Person.")
Maintain an open airway while you pinch the injured person's nose shut.
Give two long, slow breaths, being sure to maintain a seal between your mouth and his or hers.
Check again for breathing and pulse (see "How to Check Airway, Breathing and Circulation").
Perform rescue breathing if the person has a pulse, but is not breathing (see "How to Provide Rescue Breathing for an Adult").
Begin CPR if the person is neither breathing nor has a pulse.
Position the hands: find the lower tip of the breastbone. Measure two finger widths towards the head, and place the heel of one hand in this location.
Place your other hand on top of the first hand, interlacing your fingers of both hands.
Lean forward so that your shoulders are over your hands.
Push downward on the chest, using the weight of your upper body for strength. Compress 15 times in 10 seconds.
Give two more slow breaths after the 15 compressions.
Do 15 more compressions followed again by two slow breaths.
Perform the 15-compression, two-breath cycle a total of four times.
Re-check pulse and breathing.
Continue repeating this entire cycle - four sets of chest compressions and breaths followed by re-checking pulse and breathing - until the injured person regains a pulse, until professional medical help arrives, or until you are too exhausted to continue.