ABSTRACT
I. DEFINITION Shock is a clinical syndrome characterized by cellular ischemia in multiple organ systems. Shock may be caused by a failure of oxygen delivery (due to hemorrhage, hypovolemia, cardiac failure, or hypoxia) or by intrinsic failure of the cell to take up and utilize oxygen (septic shock, cyanide poisoning). In a description in 1872, Gross described shock as ‘‘a rude unhinging of the machinery of life’’ [1]. Although shock may be caused by a wide variety of conditions, it produces predictable effects on the body. If unchecked, shock of any variety can produce a rapidly fatal downward spiral. Even when treated aggressively, a single episode of shock can cause permanent organ system injury.
