For a casualty to be unconscious there has been an interference with the normal functions of the brain.
The causes of unconsciousness can be classified into 4 broad groups:
Combinations of different causes may be present in an unconscious person e.g., a head injury due to the influence of alcohol.
Before loss of consciousness, the person may experience yawning, dizziness, sweating, change from normal skin colour, blurred or changed vision, or nausea.
Assess the collapsed person’s response to verbal and tactile stimuli (‘talk and touch’), ensuring that this does not cause or aggravate any injury. This may include giving a simple command such as, “open your eyes; squeeze my hand; let it go”. Then grasp and squeeze the shoulders firmly to elicit a response.
A person who fails to respond or shows only a minor response, such as groaning without eye opening, should be managed as if unconscious.
If the person is unresponsive and not breathing normally, follow DRSABCD.
With an unconscious breathing person, care of the airway takes precedence over any injury, including the possibility of a spinal injury (Guideline 9.1.6). An unconscious person must be handled gently, and every effort made to avoid any twisting or forward movement of the head and spine.
An unresponsive person who is breathing normally be positioned into a lateral, side-lying recovery position as opposed to leaving them supine.