WHAT IS BLOOD CLOTTING ?

Bleeding

If your skin is cut in some way your bleed. This is good to some extent because the bleeding washes away microbes that may have got through your skin. The bleeding cannot be allowed to go on for too long though, because as you bleed you are losing valuable materials that your body has worked to get for you.



Clotting

Very quickly after you are cut a blood clot starts to form. This provides a temporary covering over the wound to allow new cells to seal the cut underneath.





Stages of blood clotting

The clotting process is a complex one, but simplified it involves an enzyme thrombin produced by blood platelets at a damage site changing a soluble protein fibrinogen in the blood into an insoluble protein called fibrin. This fibrin is what forms the mesh in the picture. Red cells then get stuck in this mesh and the whole thing dries pulling the wound together and sealing it.



Haemophilia - some people (usually males) lack one of the blood clotting factors, as a result of a genetic disease. As a result their blood doesn't clot and they are at risk of bleeding to death if injured. Hospitals provide them with the missing factor so they can inject this if it is required.

STROKE

Definition of a Stroke:

Cerebrovascular Accident (CVA) involves interruption of the flow of blood to the brain, due to blockage or hemorrhage of the blood vessels. Cells begin to die with in 4 minutes.

Types Of Strokes

1.Hemorrhagic: Artery in the brain begins to bleed due to weakened area of the blood vessel, such as an aneurysm.

2.Ischemic: A blood clot occludes the artery and blood flow ceases causing cell death.

The severity of the stroke is determined by the area of the brain affected and the extent of damage. A stroke on the left side of the brain affects the right side of the body. Alternately, a stroke on the right side of the brain affects the left side of the body.


Symptoms:

•Tingling and weakness of the face or extremities
•Visual impairment
•distorted speech
•Confusion
•Unsteady gait, dizzy
•Complaints of headache


Other Signs Include:

•Unable to communicate and appears confused
•Paralysis of an extremity on either side of the body

PLAGUE FORMATION

BLOOD CLOTTING MECHANISM (FLOW CHART)

BLOOD CLOTTING MECHANISM

Deep Vein Thrombosis Explained


A thrombosis is the formation of a blood clot in a blood vessel. Deep vein thrombosis (DVT) is a form of thrombosis that develops in one of the deep veins of the body.

DVT often begins in the calf or thigh because blood moves relatively slowly in these areas, particularly if exercise is limited. As the blood begins to pool in an area, a clot develops and can attach itself to the wall of a vessel or in more severe cases become wedged within a vessel, blocking blood flow.

Blood clots are common. And while a blood clot itself is not life threatening it can cause serious complications. Professor Reginald Lord, head of the vascular group of St. Vincent's hospital in Sydney, says only one percent of venous thromboses cause complications.

As a clot develops in size, it can shed pieces of the clot. These are referred to as emboli. The emboli float through the blood system and can travel through the heart to major arteries in the lung causing serious and sometimes fatal complications.

One of the most serious is referred to as a pulmonary embolism where blood flow to the lung is blocked.