"Vein thrombosis is a pathological condition that occurs as a result of blood clotting disorders and blockage of blood vessels. As a result of the accumulation of thrombotic masses in the veins, they can be partially or completely blocked, which often leads to damage to the walls of blood vessels. Pathology can occur in almost any vein of the human body ", however, the vessels of the lower extremities and pelvis are often affected. One of the most dangerous types of venous thrombosis is considered to be blockage of the inferior vena cava, the main inflow to the heart. Then the blood flow stops about 30 centimeters from the heart, and this narrows the vessels up to the pulmonary arteries." Coagulation in the medical context means the process of “clotting” blood. Thrombogenesis is an important function of the body. The slightest damage to the vascular wall causes the formation of the first platelet layer, which protects the vessel from further damage. At this point, the blood clots to prevent further bleeding and the flow of new platelets and fibrinogen to the damaged area, leading to the formation of a blood clot. When a blood clot appears, it gradually increases in size, forming a denser coagulative clot. This process ensures the safety of the vessels and their protection from damage. If a blood clot completely blocks the lumen of a vein, then neither blood nor lymph can escape - so-called “thrombophlebitis” is formed. This is accompanied by painful sensations and tissue swelling. The temperature may rise, and the skin over the site of the lesion will be hot to the touch. In severe cases, blood coagulation disorders can lead to pulmonary embolism, which can be fatal if