Thrombosis and haemostasis
Thrombosis is the blood clot which occurs in a blood vessel.
The classification of thrombosis
Venous thrombosis is the formation of a blood clot in a vein.
Deep vein thrombosis is the formation of a blood clot in a deep vein. It is usually affecting the leg vein, like the femoral vein. It exists some important factors in the formation of a blood clot inside a deep vein like the estimation of the blood flow, the thickness of the blood and the vessels wall qualities.
Portal vein thrombosis, affects the hepatic portal vein, which leads to portal hypertension and the decrease of the blood supply to the liver.
Renal vein thrombosis is the occlusion of the renal vein by a thrombus. This results in decreasing the drainage from the kidney.
Jugular vein thrombosis occurs due an infection, or to the use of an intravenous drug.
Cerebral venous thrombosis is a stroke which occurs due to the blockage of the dural venous sinuses by a thrombus.
Arterial thrombosis is a thrombus formation inside an artery.
Myocardial infarction ends with an infarct, because of the occlusion of the coronary artery by a thrombus. It may become fatal if does not receive fast medical treatment.
Hepatic artery thrombosis usually occurs after the liver transplant.
Arterial embolus. This can be formed in the limbs.
Thrombosis and haemostasis pictures
Haemostasis
Haemostasis is a complicated process that stops the process of bleading. It is reffering to the process of keeping the blood inside a damaged blood vessel.
Haemostasis includes the changing of blood from a fluid state to a solid one. The intact blood vessels are moderating the clotting of the blood. The endothelial cells of the intact vessels are preventing blood from coagulation by heparin secretion.
The three big steps of haemostasis.
- Vasoconstrictive paracrine which causes immediate contraction of the injured vessels. Vasoconstriction is realised by the endothelium. This first step decreases blood flow and the pressure inside the vessel. When the pressure is put on a bleeding injury, the blood flow inside the vessel decreases.
- the second step is the mechanical blockage of the rupture by a platelet plug. The plug becomes activated, and releases cytokines in the area that surrounds the damage.
- the last step is the blood coagulation, which is a clot formation that seals the rupture until the tissue is repaired. The blood coagulation has a series of enzymatic reactions that results in the formation of a fibrin protein fiber mesh that help at the stabilization of the platelet plug. The new platelet plug is called a clot. However, some chemical factors that are involved in the blood coagulation are promoting platelet adhesion and aggregation in the region that has been injured.
The injured vessel is repairing itself, and the clot back off and is slowly dissolved by the enzime plasmin. Some abnormalities in the normal physiological result of the body in preventing and stopping the haemorrhage.
Haemostasis is maintaining in the body due to three mechanisms like such as: the vascular spam meaning the damaged blood vessels constrict, the platelet plug formation meaning that the platelet sticks to the injured endothelium for forming platelet plug which is also called the primary hemostasis and then degranulate, the blood coagulation meaning that the clots are forming upon the transformation of the fibrinogen to fibrin, and its addition to the platelet plug, and this is also called secondary haemostasis.
