Shock is the slowing of blood flow to the vital organs (brain, lungs, heart, kidneys and others). Shock occurs when blood pressure and flow are not strong enough to force blood through to the vital organs.
There are many forms and causes of shock. The most common ones are a weak heart, too little blood or a severe infection.
Treatment depends on the cause of shock but usually is aimed at restoring blood pressure.
Shock is very dangerous. Many patients die each year from the complications of shock. The clinical term is as defined above and differs from common, non-medical usage of the term "shock". For example, when a person is unexpectedly given tragic news, such as the death of a loved one, we often say that person "is in a state of shock." This state of mental anguish, disbelief and temporary confusion is very different and much less serious than the medical definition of shock.
Related LinksNational Library of Medicine
The National Library of Medicine website provides extensive information regarding the shock patient.