kiss of life

Emergency mouth-to-mouth resuscitation in which the operator blows air into the victim's lungs to inflate them, allowing air to be exhaled automatically.

Mouth-to-mouth resuscitation.

The noun has one meaning:

Meaning #1: 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
  Synonyms: cardiopulmonary resuscitation, CPR, cardiac resuscitation, mouth-to-mouth resuscitation