General Principles When someone is unconscious
General Principles When someone is unconscious, all muscles are relaxed. If they are left lying on their back, the tongue, which is attached to the back of the jaw, falls against the back wall of the throat and blocks air from entering the lungs. Other soft tissues of the airway may worsen this obstruction.
The mouth falls open but this tends to block, rather than open, the airway. The unconscious person is further at risk because of being unable to swallow or cough out foreign material in the airway. This may cause airway obstruction, or laryngeal irritation and foreign material may enter the lungs.
For this reason the rescuer should not give an unconscious person anything by mouth, and should not attempt to induce vomiting. If foreign material irritates the vocal cords, a protective reflex muscular spasm (laryngeal spasm) prevents the entry of material into the lungs.
This may result in partial or complete airway blockage of the entrance to the trachea (windpipe) with the person often making an abnormal noise (stridor) during attempts to breathe.
Airway closure due to laryngeal spasm can be complete; in this case there is no noise (stridor) because there is no airflow. That can persist until the person becomes blue or unconscious from lack of oxygen.
When consciousness is lost, the spasm usually relaxes In an unconscious person, care of the airway takes precedence over any injury, including the possibility of spinal injury (Refer to Guideline 9.1.6).
All who are unconscious should be handled gently with no twisting or bending of the spinal column and especially the neck. If it is necessary, move the head gently to obtain a clear airway. Where possible, an assistant should support the head when an injured person is being moved, but no time should be wasted in detailed positioning.