A. Q: What is deep vein thrombosis?
A: Deep vein thrombosis (DVT) is a medical term that refers to the formation of blood clots in the deep veins of the lower extremities, which can sometimes lead to life-threatening conditions.
If a blood clot forms in a blood vessel, it can block the vessel, which can lead to obstruction of blood flow. When this happens in the deep veins of the lower extremities, stagnation of blood flow to the lower extremities occurs, leading to localized swelling and pain.
On the other hand, when a venous thrombosis forms, the clot can circulate with the blood flow to other parts of the body, blocking the blood vessel in question. For example, when a blood clot forms in a lower extremity vein, it can travel with the bloodstream to the lungs, which can cause symptoms of respiratory distress. When the clot is large, it can lead to death. When a blood clot reaches the lungs with the circulation, it is called a “pulmonary embolism” or “PE”.
Q: What are the symptoms of “DVT”?
A: DVT can cause the following symptoms.
Swelling
Pain
Increased local skin temperature or redness of the skin
Sometimes, blood clots occur in the superficial veins near the surface of the skin, which is called “superficial vein thrombosis”. Superficial vein thrombosis can cause different symptoms, it can lead to more intense pain, localized redness of the skin, and even infection. Superficial vein thrombosis can sometimes cause localized veins to stiffen and protrude from the skin, usually below the plane of the knee.
If you suspect you have a deep vein thrombosis in a lower extremity, contact your doctor or nurse for help immediately. Superficial vein thrombosis is less dangerous, but deep vein thrombosis in the lower extremities is more dangerous. Your doctor or nurse will do the relevant tests to diagnose whether you have a thrombosis, and if necessary, further treatment.
Q: What are the symptoms of pulmonary embolism?
A: Pulmonary embolism can cause the following symptoms.
Shortness of breath or difficulty in breathing
Sudden chest pain that worsens with breathing movement
Cough or hemoptysis
Tachycardia
If you have any of these symptoms, especially if they occur within a short period of time (hours or days) or get worse quickly, call 120 immediately for help. At the hospital, your doctor will be able to check quickly to see if you have a blood clot. Pulmonary embolism can lead to death, so you need to act quickly to find out if you have a blood clot as soon as possible.
Q: How should I treat deep vein thrombosis?
A: The treatment of deep vein thrombosis is mainly to prevent the thrombus from further aggravating and reaching the lungs, including injectable medication and oral medication. Most patients with lower extremity DVT will first be treated in the hospital.
Patients with DVT are usually given drugs to prevent thrombosis, called “anticoagulants”, “blood-thinning drugs” or “antithrombotics”. Almost all patients are on oral anticoagulants for at least 3 months. Some patients receive subcutaneous “heparin” injections for several days, or for longer periods for those who cannot take oral anticoagulants.
The role of anticoagulants is not to dissolve the clot that has formed, but to prevent further aggravation and formation of the clot. It is important to stay on anticoagulants for more than a few months because the body needs time to dissolve clots that have formed, and patients who have clots are at risk of having another clot in the first few months.
Several common oral anticoagulants include: warfarin (coumarin class), rivaroxaban (trade name: Bactrim), apixaban (trade name: Eladol), and edoxaban. If your doctor prescribes any of these anticoagulants, you will need to take them as prescribed. If you miss a dose, ask your doctor for a remedy. When you start taking anticoagulants, you will need to have blood-related tests. If you are taking warfarin, you will need to have routine coagulation tests and your doctor will adjust the appropriate dose based on your blood test results. If the dose is wrong, it can cause ineffective medication or severe bleeding. All anticoagulants carry a risk of bleeding, so your doctor will always watch you for signs of bleeding-related problems.
When patients are unable to use anticoagulants or when anticoagulants are not effective, there is another treatment option called “inferior vena cava filter” therapy (IVC Filter). A filter is used to stop and filter larger blood clots from reaching the heart, and is recommended when you have
there is a contraindication to taking warfarin and other anticoagulant drugs
you still have a blood clot on warfarin or other anticoagulant drugs
Life-threatening bleeding while taking warfarin or other anticoagulants
Severe lower extremity deep vein thrombosis that can cause fatal pulmonary embolism
In some cases, some patients have severe blood clots that cause gangrene (disruption of blood supply to the lower extremities). When this happens, the doctor may choose to apply a clot-dissolving drug. This is usually done by inserting a catheter into the deep vein and applying the thrombolytic drug locally. For some patients, the doctor may also choose to remove the clot surgically.
Q: Are there ways to prevent thrombosis?
A: Yes. Some patients develop venous thrombosis from sitting for too long. For example, people who travel long distances by air have a higher risk of thrombosis. When you fly for long periods of time, you can do the following to prevent the formation of blood clots.
Stand up and walk after 1-2 hours of sitting still
Try not to smoke before traveling
Try to wear loose fitting clothes
Move your position and lower limbs frequently when sitting
Drink as much water as possible
Wear long socks above the knee if possible
Avoid drinking alcohol and taking medication for sleep as this will reduce your activity