What is deep vein thrombosis?
Veins are the blood vessels that allow blood to flow back to the heart. The deep veins travel with the arteries, between the muscles, and connect to the body’s largest vein, the inferior vena cava. Deep vein thrombosis is the formation of blood plaques in the deep veins that cause sudden swelling, pain or warmth in the limbs, often with acute onset. Deep vein thrombosis can cause a serious complication, pulmonary embolism.
In this case, the thrombus can be dislodged from the deep vein and circulate through the bloodstream, leading to pulmonary embolism, which can be life-threatening and requires prompt treatment. Lower extremity deep vein thrombosis and pulmonary embolism are so closely related that the two conditions are clinically grouped into one disease-venous thromboembolism syndrome.
Symptoms of lower extremity deep vein thrombosis?
The main symptoms are sudden swelling and pain in the lower extremity, the thrombosed lower extremity is thicker than the healthy side, and there is obvious pressure pain in the calf muscle. Patients may experience pain in the lower extremities when walking, and in severe cases, they may not be able to walk on the ground, and the skin color of the lower extremities may change, such as bruising or dark red.
What is pulmonary embolism?
The blood collected in the veins of human body contains less oxygen after metabolism by tissues and organs. The venous blood returns to the right heart and spreads to the lungs through the pulmonary artery, which forms arterial blood after completing oxygen exchange and then supplies to the whole body. Pulmonary embolism is a life-threatening condition in which a thrombus in the vein comes off and blocks the pulmonary artery, making the exchange of oxygen and carbon dioxide in the lung incomplete and preventing the supply of oxygen to the tissues.
What are the symptoms of pulmonary embolism?
After pulmonary embolism occurs, depending on the extent and severity of the embolism, chest tightness and shortness of breath, breath-holding, coughing up blood, chest pain, labored breathing, etc. In severe cases, sudden syncope or even sudden death may occur.
What causes deep vein thrombosis of lower limbs?
The three major factors of deep vein thrombosis: stagnant venous blood flow, venous wall damage and blood hypercoagulation. Venous thrombosis is the result of a combination of etiological factors. The causes of DVT include: hypercoagulable blood after major surgery; prolonged bed rest resulting in blood stasis; prolonged travel (economy class syndrome); genetic deficiency or abnormality of coagulation factors; malignancy; obesity, history of heart attack, stroke or congestive heart failure, pregnancy, birth control pills or inflammatory bowel disease increasing the risk of DVT.
What tests are needed for lower extremity deep vein thrombosis?
Patients with sudden swelling and pain in the limbs should suspect the possibility of deep vein thrombosis, and we usually conduct a detailed investigation with the help of some tests. For patients with suspected venous thrombosis, we perform Doppler ultrasonography, which is simple, quick, non-invasive and in most cases gives us a clear diagnosis or hint, and then some patients with thrombosis are really not easy to diagnose, then we perform some larger tests such as CT angiography, which help us to detect most of the thrombosis in time, and then finally clarify whether it is thrombosis or not. Venography is also needed, which is the gold standard for diagnosing thrombosis.
How to treat deep vein thrombosis?
Once a DVT is detected, the severity needs to be assessed by a vascular surgeon and anticoagulant medication applied as soon as possible. Anticoagulants prevent blood clotting and are the basic treatment for venous thrombosis. Further aggravation of venous thrombosis is avoided with the use of anticoagulants. Commonly used anticoagulants include heparin and warfarin, etc. There is a risk of bleeding while anticoagulation, so they need to be used under the guidance of a doctor.
If some patients cannot use anticoagulants due to their condition, it is time to consider placing an inferior vena cava filter, which can stop the lower extremity deep vein thrombosis from dislodging and prevent pulmonary embolism. For patients who are at high risk for thrombosis and require surgery, we usually place an inferior vena cava filter before the patient’s surgery to prevent pulmonary embolism.
A freshly formed thrombus that is loosely bound to the vein wall will be easily dislodged for pulmonary embolism to occur, however, in some patients the thrombus is formed to a greater extent and over time the thrombus becomes tightly bound to the venous vessel wall, forming an old thrombus. Although these old are not easy to fall off, but still exist with the blood vessels, blocking blood flow, resulting in distal venous reflux, also on the basis of this will again form thrombosis, clinically known as this phenomenon is post-thrombotic syndrome. Therefore, once intravenous thrombosis is detected, early opening of blood vessels can prevent the occurrence of post-thrombotic syndrome and improve the quality of life. With the development of medical technology, nowadays it is possible to open the blood vessels blocked by thrombosis early by placing thrombolysis tubes under intervention and minimally invasive mechanical thrombectomy, which can solve the problem of thrombosis blocking blood vessels.
What measures can be taken to prevent deep vein thrombosis?
For inpatients, physicians will assess the risk of DVT on a case-by-case basis and recommend perioperative prophylactic use of anticoagulants (under physician supervision) for high-risk patients, lower extremity circulation drives and compression stockings to prevent DVT formation. Early out-of-bed activities for post-operative patients, active flexion and extension of lower limbs in bed and avoiding prolonged limb prostration can prevent deep vein thrombosis.
In normal life, we can prevent thrombotic diseases by doing the following: develop good habits, quit smoking; maintain a low-fat, high-fiber light diet; develop the habit of drinking more water, especially after exercise, pay attention to timely replenishment of water to reduce blood viscosity and prevent the occurrence of venous thrombosis; appropriate activities to promote blood reflux; prevent constipation, eat more fruits and vegetables, and take laxatives to soften the stool when necessary. In order to reduce the abdominal pressure during defecation, which is conducive to the return of blood flow; dress comfortably and avoid wearing tight clothes.