Why do you raise the feet 12 inches for a person in shock?

Shock is a state in which the body is experiencing a lack of blood flow, either due to blood loss, infection, cardiac arrest or failure, or spinal injuries. Consequently, the body's natural response is to decrease blood flow to the extremities and send it to the internal organs, which can result in not enough blood going to the brain, resulting in brain damage. Raising the victim's feet helps encourage blood flow to the brain (and other vital areas.) One's legs can go much longer with less oxygen than one's brain can.