Shock is the term for bodily changes that follow such trauma as dehydration, allergic reaction, or serious injury (burns, fractures, crushing, prolonged bleeding). A person in shock usually has pale, clammy skin; a weak and irregular purse; and decreased blood pressure.
His breathing may be shallow and he may feel faint, nauseated, chilled, or thirsty– symptoms of the body’s channeling blood to the vital organs and the brain. In the early stage, he may be agitated; try to reassure him that his injury is being cared for. Later, he may become unresponsive and, finally, unconscious.
Shock symptoms aren’t always immediately obvious. Assume they may develop in anyone with a serious injury. In any case, they should be treated only by medical professionals. Summon help immediately; do what you would normally do for the particular injury or other trauma involved.
In addition, aid blood flow by having the victim lie flat: raise his legs about 8 inches unless you suspect a head injury. Cover the victim lightly in mild weather or if he is indoors, more warmly outdoors in winter. Do not use artificial heat (pads, hot-water bottles) except for hypothermia. Offer no liquids, except water for dehydration or burns.