To perform mouth-to-mouth resuscitation on an injured person, what must you do first?

Correct answer: Clear and open the airway.

Before giving mouth-to-mouth resuscitation, you must open the airway, because if the tongue or something in the mouth blocks it, air cannot reach the lungs. Use the head-tilt, chin-lift maneuver, with one hand on the forehead and two fingers of the other hand under the chin, as shown in the image. If you see an object you can reach, remove it with your index finger bent into a hook, but don't put your fingers in blindly. Pinching the nose shut comes afterward, when you blow air in. The recovery position is for someone who is breathing, and mouth-to-mouth resuscitation is performed with the injured person lying on their back.

Manual IX — Primeros auxilios (2026) · Resuscitation Council UK — First Aid Guidelines 2025