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Loss of blood, haemorrhaging and letting blood

Category: Illnesses and disabilities



Introduction and description

Bleeding, technically known as haemorrhaging  is the loss of blood or blood escape from the circulatory system.  Bleeding can occur internally, where blood leaks from blood vessels inside the body or externally, either through a natural opening or through a break in the skin.



Bleeding  causes loss of nutrients in the longer term, but in the short term it can result in hypoxia - lack of oxygen to the brain, which causes light headedness, dizziness, fainting, in severe cases coma and hallucinations, out of body experiences, visions and in extreme cases near death experiences.  


The principle cause of loss of blood and haemorrhaging is  Surgery and other physical trauma - thus any form of wound or physical damage, included in this we have:

  • Being badly wounded
  • Internal damage – for example damage to a blood vessel that in turn causes blood to collect under the skin. Contusions and bruises damage tissue under the surface of the skin but rarely cause enough bleeding to result in heavy loss of blood
  • Burst aneurysm  - an aneurysm is a blood-filled balloon-like bulge in the wall of a blood vessel, usually the arteries.  Anaeurysms can occur, for example, at the base of the brain (the circle of Willis) and aortic aneurysms occur in the main artery carrying blood from the left ventricle of the heart.   When the size of an aneurysm increases, there is a significant risk of rupture, resulting in severe hemorrhage. Aneurysms can be hereditary or caused by disease, both of which cause the wall of the blood vessel to weaken.

Although traumatic bleeding is directly linked with some type of injury, there are some contributory factors that make the risk of bleeding worse.  For example:

  • Inherited genes - some people are born with illnesses that increase the risk of their bleeding ad losing blood, for example:
    • Haemophilia is a group of hereditary genetic disorders that impair the body's ability to control blood clotting or coagulation, which is used to stop bleeding when a blood vessel is broken. Haemophilia A (clotting factor VIII deficiency) is the most common form of the disorder, present in about 1 in 5,000–10,000 male births. Haemophilia B (factor IX deficiency) occurs in around 1 in about 20,000–34,000 male births.  Like most recessive sex-linked, X chromosome disorders, haemophilia is more likely to occur in males than females.
    • Von Willebrand disease (vWD) is the most common hereditary coagulation abnormality described in humans, although it can also be acquired as a result of other medical conditions. It arises from a qualitative or quantitative deficiency of von Willebrand factor (vWF), a multimeric protein that is required for platelet adhesion. It is known to affect humans and dogs (notably Doberman Pinschers), and rarely swine, cattle, horses, and cats. There are three forms of vWD: inherited, acquired, and pseudo or platelet type. There are three types of hereditary vWD: vWD Type I, vWD Type II, and vWD III. Within the three inherited types of vWD there are various subtypes
  • Pharmaceuticals - a number of pharmaceuticals cause the blood to 'thin' and increase the risk of bleeding, some are deliberately designed to thin the blood to help with heart disease, for example
    • Warfarin and other blood thinners ("Coumadin" and others) -  bleeding risk can be markedly increased by interactions with other medications. Warfarin acts by inhibiting the production of Vitamin K in the gut. Vitamin K is required for the production of the clotting factors, II, VII, IX, and X in the liver. One of the most common causes of warfarin-related bleeding is taking antibiotics. The gut bacteria make vitamin K and are killed by antibiotics. This decreases vitamin K levels and therefore the production of these clotting factors
    • Pain killers and NSAIDs - One of the most common causes of increased bleeding risk is exposure to non-steroidal anti-inflammatory drugs (or "NSAIDs"). The prototype for these drugs is aspirin, which inhibits the production of thromboxane. NSAIDs inhibit the activation of platelets and thereby increase the risk of bleeding. The effect of aspirin is irreversible; therefore, the inhibitory effect of aspirin is present until the platelets have been replaced (about ten days). Other NSAIDs, such as "ibuprofen" (Motrin) and related drugs, are reversible and therefore, the effect on platelets is not as long-lived.


Although you may find this hard to believe, the Australian Aborigines deliberately bled themselves in order to promote a spiritual experience, as did the Native American Indians.

For more details on the types of haemorrhaging see Haemorrhaging in the science section.

How it works

The principle cause is hypoxia.

see also Blood circulatory system disease

Related observations