How do I check if an unconscious victim's airway is open?

When assessing an unconscious victim's airway, the mantra "look, listen, feel" should come to mind. First, watch for the victim's chest to rise and fall as it fills with and expels air. Next, position your ear and cheek near the individual's mouth and nose to listen for the sound of air movement. Finally, try to feel the victim's breath on the skin on your cheek, or use your hand to see if you can feel any air moving in and out from the victim's mouth or nose.