The first-aid procedure combines external heart massage (to keep the blood flowing through the body) with artificial respiration (to keep air flowing in and out of the lungs). The victim is placed face up and prepared for artificial respiration. The person administering CPR places his or her hands (one on top of the other, with fingers interlocked) heel down on the victim's breastbone, leans forward, and makes 30 quick, rhythmical compressions (at a rate of about two per second) of about 2 in. (5 cm). This is followed by two breaths, administered using the mouth-to-mouth method of artificial respiration. CPR for infants and children differs in the ratio of compressions to breaths, and the compression of the chest is only 1 to 1.5 in. (2.5 to 3.8 cm). Ideally the procedure is done by two people, one to give mouth-to-mouth artificial respiration and one to apply external heart massage, and special training is recommended. External heart massage alone may be given if a person is unwilling or unable to provide artificial respiration; studies have shown that heart massage alone can be as effective as both techniques combined.
Cardiopulmonary resuscitation in the hospital is an aggressive technique employing drugs and defibrillation equipment, which administers an electrical shock to the heart in an attempt to restore the heartbeat. There is some controversy surrounding its use in patients whose prognosis is poor.
Emergency procedure to restore breathing and circulation in an unconscious person. A trained rescuer opens the airway and confirms the absence of breathing and pulse. Resuscitation itself consists of alternating mouth-to-mouth breathing (see artificial respiration) and repeated pressure on the chest to circulate the blood.
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