mouth-to-mouth resuscitation

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun A technique used to resuscitate a person who has stopped breathing, in which the rescuer presses his or her mouth against the mouth of the victim and, allowing for passive exhalation, forces air into the lungs at intervals of several seconds.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun A first aid technique to return an unconscious person's respiration by pressing the rescuer's mouth against the mouth of the patient and blowing air into his/her lungs.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun an emergency procedure consisting of external cardiac massage and artificial respiration; the first treatment for a person who has collapsed and has no pulse and has stopped breathing; attempts to restore circulation of the blood and prevent death or brain damage due to lack of oxygen