Start by determining whether the victim is conscious. Ask the victim -
go: “Do you need help?” If there is no response, squeeze the victim's trapezius muscle (Figure 3-2).
Do not push or move the victim. A person who does not respond to external stimuli may be unconscious. This condition can be life-threatening. When a person loses consciousness, the tongue muscles relax and the tongue recedes (Figure 3-3), leading to airway obstruction—respiratory arrest and subsequent cardiac arrest.
During the initial examination, you check the patient's airway, breathing and pulse.
Step one (A): airway. Step two (B): breathing. Step three (C): pulse.