A venous thromboembolism begins as a clot and moves to another location within a vein, eventually causing an obstruction. Venous thromboembolisms might occur anywhere throughout the venous system, producing symptoms based on location. The clot generally occurs due to inhibition of blood flow, or a system irregularity causing hypercoagulation. Venous thromboembolism treatment typically involves eliminating the clot and correcting any underlying problem.
A deep vein thrombosis is a venous thromboembolism that lodges in an arm or leg. The symptoms may include swelling, pain in the affected area, and, possibly, warmth. A pulmonary embolism is a clot which has traveled to the lung and may eventually enter the heart, causing a heart attack. Venous thromboembolism symptoms in this region usually produce chest pain, difficulty breathing, increased heart rate, and profuse sweating. Persons experiencing a clot obstruction in the central nervous system might experience headache, nausea and vomiting, seizures, or stroke symptoms.
Any number of factors can contribute to blood flow disturbances. Swelling from injuries, infections or certain cardiac conditions often slow or restrict normal flow, which sets the conditions for clot formation in motion. The valves within the veins normally act to keep blood flowing toward the heart. With normal aging, however, these valves weaken, causing possible backflow, pooling, and subsequent clot formation. As blood pools in a region, chemicals in the body cause the development of a fibrin mesh, which traps blood cells and other blood components.
Insufficient physical activity or physical impairment and immobilization may also cause reduced blood flow. Internal catheters and synthetic heart valves can also inhibit proper blood flow and contribute to venous thromboembolism formation. Some individuals have genetic disorders which produce protein deficiencies, malformed clotting factors, or other abnormalities that cause hypercoagulation and susceptibility to blood clot formation.
Physicians usually treat susceptible patients with oral anticoagulant medications along with periodic lab studies that monitor clotting ability. These medications include aspirin or warfarin and usually act by inhibiting clotting factors or platelet clumping. Health care providers might also recommend the use of compression stockings, which are thought to promote venous blood flow and prevent backflow by faulty valves. Physicians might treat patients having genetic disorders by replacing the component in which the patient is deficient.
Health care providers generally use venous thromboembolism guidelines that indicate a particular course of treatment. Physical assessments and lab studies generally determine possible coagulation abnormalities, and image studies indicate the location and extent of the obstruction. Treatment initially includes administration of oral or intravenous anticoagulant medications. Physicians might also use thrombolytic, or clot busting medications, including alteplase or streptokinase. These medications cause the fibrin mesh to deteriorate and dissolve the clot.