1. Substantial loss of blood volume, as in a severe laceration
2. Decreased heart function from Injury or illness, such as a heart attack or trauma to the chest, leaving the heart unable to pump sufficient blood to the tissues
3. Dilation of the blood vessels, making the "container" larger than normal, as in anaphylactic shock
Recognizing the onset of shock isn't always easy, but it doesn't make any difference, because you always treat for shock from the very beginning of your rescue! If you wait until you think the victim is going into shock, it is probably too late.
So how do you treat for shock?
1. First, treat the underlying pathology. For example, stop the bleeding
2. Second, place the person in a "position of comfort." Lying down is often best, but not always. Heart attack victims often can't breath when they are lying down, and some people will feel claustrophobic or panicky in a prone position. Ask them how they feel most comfortable.
3. Maintain body temperature. We used to say, keep the patient warm, but this is clearly inappropriate on a high humidity, 100 degree day.
4. Reassure the person. This is extremely important. As discussed in a previous post, your voice and calmness can go a long way toward keeping a person from panicking. Talk to the individual, but slowly and calmly and with good eye contact. Don't be afraid to interject a little humor if it seems appropriate. Surprisingly, sick or hurt people often joke about their condition. Play along with them.
As always, be careful not to discuss the patient's condition within his or her hearing.
Shock can be deadly, so remember: Always treat for shock from the very beginning!