Bleeding

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Bleeding
Other names	Hemorrhaging, haemorrhaging, blood loss
A bleeding wound in the finger
Specialty	Emergency medicine, hematology
Complications	Exsanguination, hypovolemic shock, coma, shock

Bleeding, hemorrhage, haemorrhage or blood loss, is blood escaping from the circulatory system from damaged blood vessels. Bleeding can occur internally, or externally either through a natural opening such as the mouth, nose, ear, urethra, vagina, or anus, or through a puncture in the skin. Hypovolemia is a massive decrease in blood volume, and death by excessive loss of blood is referred to as exsanguination.^[1] Typically, a healthy person can endure a loss of 10–15% of the total blood volume without serious medical difficulties (by comparison, blood donation typically takes 8–10% of the donor's blood volume).^[2] The stopping or controlling of bleeding is called hemostasis and is an important part of both first aid and surgery.