Internal bleeding is when bleeding occurs inside the body. It may be caused by concussions, high blood pressure (by causing blood vessel rupture) or other forms of injury, especially high deceleration occurring during a car accident (organ rupture). It is, depending from where it occurs (i.e. the brain), a kind of medical emergency, that might cause death in a short period if not given a proper treatment quickly.

Internal bleedings are usually called hemorrhage, even though the term is general to all kinds of bleedings.

A minor case of internal bleeding is the ecchymosis (bruise): blood expands under the skin, causing a blue stain. Other cases of internal bleeding are serious for two reasons:

• the blood can compress organs and cause their dysfunctioning (haematoma);
• when it does not stop spontaneously, the loss of blood cannot be controlled.

It is not possible to recognise an internal bleeding without specific medical investigation. The external signs are general signs of hypovolemic shock (see the article about shock for more information).