A deep vein thrombosis (DVT) is a blood clot or thrombus that develops in deep vein usually in leg. Here they pass through the centre of leg, surrounded by muscles and less commonly DVT occurs in deep veins of arm of pelvis.
DVT is primarily related to the stasis of blood flow, vascular wall damage, activation of clotting system and hypercoaguable state. Blood passing through the deepest vein in calf or thighs flows relatively slow then from a solid clot which becomes wedged in the veins. The deep veins are responsible for returning the blood to heart and lungs and these veins weaken their functions of propelling blood over a period of time especially when a person is confined to immobilization. Presence of hypercoagulable state such as pregnancy, deficiency of antithrombin III, protein C and protein S, myeloproliferative disorders and other hyper viscosity syndrome increase the vulnerability for DVT.
DVT is common in individuals who have a long distance travels especially in the aircraft or car. The commonest risk factors are highly after the age of forty with prolonged immobilization such as prolonged bed rest due to medical and surgical ailments such as respiratory failure, heart failure, paralysis, after fracture pelvis or femur, trauma or accident, extensive abdominal, and in cancer patients.
The commonest complications of DVT are – fatal pulmonary embolism. DVT can be prevented by regular physical activity especially if an individual is immobilized for longer time. People who already had a DVT can take some precautions to avoid uncomfortable complications. Taking a low dose of aspirin before a long flight may reduce a risk. There are number of things you can do to reduce your risk, such as stop smoking if you do that, and losing weight if you are overweight. Wearing the compression stockings may also be advised for those at risk of developing a DVT. Immediately after an operation, people are encouraged to get out of bed as early as possible. It can also stop new blood clots from forming and old ones from getting bigger. If you are having surgery then you must know that surgery and some medical treatments can increase your risk of developing DVT. So if you’re going to hospital for an operation, you will usually have an assessment to check your risk of developing DVT before you have your operation. Pulmonary embolism is the most serious complication of DVT. It happens when a piece of the blood clot breaks off and travels through your bloodstream to your lungs, where it blocks one of the blood vessels.
This is serious and can be fatal. Post thrombotic syndrome is an another complication of DVT, this happens if the damage caused by a DVT permanently reduces the ability of your veins to efficiently return blood from your lower leg and leads to pooling of fluid. This can eventually lead to long- term pain and swelling. In severe cases these may lead to ulcers on your leg. Limb ischemia is a rare complication that only happens with a large DVT.
DVT is rare in young people, but usually occurring in people aged over 40. It is however recommended that you should call your doctor if you are at the risk of DVT.