Superior Vena Cava

The airways can become accidentally obstructed, hindering or preventing the passage of air. In such cases, the airway must be opened up, "ensuring the permeability of the upper airways", to enable spontaneous or artificial ventilation. This is airway clearance. Airway clearance is one of the first concerns of a first-aider when working with a victim. This is the "A" (airways) in the primary ABCs. Although a rescuer's first concern must be the environment, to ensure his or her own safety in an emergency situation. Clearing the airways is then one of the rescue steps that takes place before attempting to contact 911.