Deep vein thrombosis (DVT) means the formation of a thrombus (blood clot) inside a deep vein, usually in the thigh or calf.
As a rule, it occurs only on one leg or arm, rarely one suffers a bilateral vein thrombosis.
Causes of deep vein thrombosis
DVT is most common in people over 60 years of age, but can also be a disease in adolescents, especially in people genetically predestined for it.
Blood clots can form when blood flow in the veins is slowed or altered. As a rule, they are found in the lower limbs, rarely the arm or an upper limb is affected (about 3% of cases).
Risk factors include:
- Central venous catheter, which irritates the vessel walls in a groin vein or hinders blood circulation.
- Prolonged bedriddenness, such as postoperatively or paralysis.
If the legs are immobilized for a long time and the calf muscles are not contracted, which would serve the venous blood circulation, blood clots develop.
- Previous deep vein thrombosis or pulmonary embolism. If DVT had already occurred in the past, a recurrence is very likely.
- Positive family history of deep vein thrombosis or pulmonary embolism. If a family member suffered from these problems, the risk of developing DVT increases.
- Fractures of the pelvis, thigh, shin or fibula.
- Birth in the past 6 months.
- Previous surgery (usually on the hip or knee or, in women, the pelvis).
- Pregnant women. Pregnancy increases the pressure in the pelvic and leg veins.
Women with a hereditary coagulation disorder are particularly at risk.
The possibility of developing blood clots in pregnancy persists until six weeks after birth.
- When too many blood cells are created in the bone marrow, the blood becomes thicker and flows more slowly than usual.
- Age: older people are much more at risk, but DVT can also affect young people.
A blood clot is more likely to form in the veins of people who have other health problems or disorders, such as:
Cancer. Some types of neoplasms increase the amount of substances needed for blood clotting.
Some cancer treatments increase the risk of blood clot formation.
Inflammatory intestinal diseases. Some intestinal diseases, such as ulcerative colitis, increase the risk of DVT.
Heart failure. Those who suffer from heart failure are at greater risk for DVT because a damaged heart does not pump blood like a normal heart.
This increases the possibility of a blood clot forming.
Birth control pill or hormonal substitution therapy. Both the pill (oral contraceptives) and hormone replacement therapy can increase the risk of deep vein thrombosis.
If you sit on the plane for a long time during a flight, the risk of DVT can increase. This probability is all the higher if one or more of the risk factors described above are present.
According to the guidelines of the American College of Chest Physicians (ACCP), an anticoagulant taken as a precaution does not help. On the other hand, it is recommended to choose a place near the central aisle to stretch your legs during the trip.
Symptoms of deep vein thrombosis
Patients with deep vein thrombosis may have different discoloration of the lower extremity.
The most common abnormal shade is reddish-purple due to venous congestion and occlusion. In rare cases, the leg is cyanotic with severe occlusions of the ileofemoral vein.
This ischemic form of vein occlusion was originally called “phlegmasia caerulea dolens” (“aching blue inflammation”).
Usually the leg is severely swollen, painful and cyanotic. Often petechiae (similar to bruises) are present.In some cases, deep vein thrombosis causes no symptoms, while in others you may experience:
- Swollen legs and numbness (usually at the level of the calf and foot). If DVT occurs on the arm, the symptoms are noticeable on the forearm, wrist and hand.
- Stabbing and persistent pain in the ankle, foot or leg.
- Overheated skin in the area of the clot.
- Redness, especially at the back of the leg below the knee joint.
- Fever, but not always.
DVT usually (but not always) affects only one leg. The pain increases when the foot is bent upwards towards the knee.
If DVT is not treated, it can lead to a pulmonary embolism: A blood clot travels from the place of origin to one of the lungs.
With pulmonary embolism, serious symptoms occur, such as:
- shortness of breath, which may worsen gradually or suddenly;
- chest pain, which may become worse when inhaled;
- sudden collapse.
Both DVT and pulmonary embolism are serious diseases that require immediate examination and treatment.
Complications and risks of deep vein thrombosis
The most serious complication of untreated deep vein thrombosis is the detachment of a clot that travels through the bloodstream and is called embolism.
An embolism can remain in the brain, lungs, heart and other areas and always causes severe damage.
The massive pulmonary embolism (occlusion of the pulmonary artery) leads to the death of the person concerned in a few minutes.
Diagnosis of deep vein thrombosis
The classic calf pain in dorsiflexion of the foot (Homan sign) is an effective test, but is only noticeable in half of patients with DVT.
The muscle pain in the calf with dorsiflexion of the foot and stretched knee is considered a sign of DVT.
However, at least 50% of the Homan sign is also observed in patients without DVT.
Superficial thrombophlebitis is characterized by the finding of a section of veins palpable, thickened, subcutaneous and similar to a rope.
Forty percent of patients with superficial thrombophlebitis without varicose veins (varicosis) or other evident causes (for example, venous catheters, venous drug abuse, soft tissue injuries, etc.) have DVT.
Patients with superficial thrombophlebitis, which extends into the estuary area of the saphenous vein into the femoral vein, have an increased risk of concomitant DVT.
The most common diagnostic examinations are: phlebography, Doppler sonography and magnetic resonance imaging (MRI).
Phlebography is rarely performed and is an outdated examination.
With Doppler sonography, blood clots can be identified very precisely.
The sound waves reflect the internal structures of the leg and create an image that reveals possible anomalies.
A doctor specializing in this will examine the painful area and veins most likely to develop thrombosis:
- Saphenous vein
- Vena poplitea
- Gemellaris vein (distal zone of the leg)
- Iliac vein (proximal part of the lower limb)
- Femoral vein
Magnetic resonance tomography
Magnetic resonance imaging is particularly efficient in diagnosing DVT in the pelvic and thigh area.
This technique is increasingly used because it is non-invasive and allows simultaneous view of both lower extremities.
Differential diagnosis of deep vein thrombosis
The doctor must exclude the following diseases:
- Achilles tendonitis
- spasm, contracture, or muscle lesion
- Soft tissue injuries
- Stress fracture
- Liver disease
- Renal failure
- Nephrotic syndrome
Treatment of deep vein thrombosis
First of all, protection is necessary, physical activities and sports should be avoided, but the leg should be kept moving.
Once the symptoms have subsided somewhat, light exercises such as swimming or exercise bikes can be started.
The doctor prescribes blood-thinning medications (anticoagulants) or aspirin.
This prevents the formation of new blood clots or the increase in size of old blood clots.
Drug therapy cannot dissolve existing blood clots.
As a rule, the first drug prescribed by the doctor is heparin.
If intravenous heparin therapy is carried out, one must remain in inpatient treatment.
Newer forms of hepars can be administered by injections once or twice a day.
You may no longer need to stay in the hospital when using this newer form of hepar.
Usually, a medication called warfarin (Coumadin) is taken along with heparin.
Warfarin is taken orally.
The dosage of this anticoagulant should be determined by the doctor depending on the “prothrombin time”.
In general, warfarin takes one to three months, but in severe cases, anticoagulant therapy is longer or even a lifetime.
When taking warfarin, the development of bleeding is more likely, even during everyday activities.
Rules of conduct when taking warfarin at home:
- Take the drug at the times and in the doses prescribed by the doctor.
- Ask the doctor what to do if you miss a dose.
- Carry out frequent blood tests to determine the correct dose to take.
- Learn how and when to take other medications to avoid side effects.
Natural remedies for deep vein thrombosis
The doctor may recommend elastic compression stockings on one or both legs or give other cues to maintain outflow in the limb.
The compression stocking improves blood circulation in the legs and reduces the risk of complications from blood clots.
It is important to wear it daily.
A compression bandage is very useful for reducing symptoms and for an accelerated recovery process. The aim of the bandage is to exert pressure on the veins.
In rare cases, surgery may be needed if medications don’t work.
There are two types of surgery:
- The insertion of a filter in the larger body vein to avoid the carry-over of emboli to the lungs;
- The removal of the thrombus from the vein.
Prognosis of deep vein thrombosis
Often DVT passes again without leaving consequences, but it can occur again. Some people may have pain and swelling in their leg for long periods of time, called postthrombotic syndrome.
Among the after-effects, a change in skin color can be observed.
These symptoms can appear immediately, but they can also develop after a year.
Wearing tight stockings (for compression) even after a past DVT can help prevent this problem.
Blood clots in the thigh dissolve more easily and migrate to the lungs (to cause a pulmonary embolism there) than thrombi in the lower parts of the legs, upper extremities or other parts of the body.
Death occurs in 6% of cases of DVT and in 12% of cases of pulmonary embolism within one month of diagnosis.
The long-term outcome is generally good if there is no malignant tumor associated with it.
Recovery times are long, drug therapy must be carried out for at least 2-3 months.
Blood tests must be carried out until the prothrombin time (PT) is correspondingly high.
Prevention of deep vein thrombosis
Preventing deep vein thrombosis is easier than treating it after it has occurred.
Some preventive measures:
Nutrition is crucial to prevent the formation of thrombi. Omega-3 fatty acids lower cholesterol and triglycerin levels in the blood, even fiber-rich foods prevent the absorption of fats in the intestine and give a feeling of satiety.
It is important to maintain an antioxidant-rich diet (vitamins A, C, E) with plenty of fruits and vegetables to protect blood vessels.
You should know how much vitamin K you are consuming when taking blood thinners.
Vitamin K can act on the function of medications such as warfarin. Foods high in vitamin K include green leafy vegetables and canola or soybean oil.
The medication should be taken exactly as prescribed by the doctor.
After surgery, such as orthopedic surgery, you will probably need to take blood thinners during your hospital stay.
When sitting for a long time, you should perform exercises with the calf muscles. Whenever possible, you should get up and walk a few steps.
If it is not possible to get up and walk around, you can simply raise and lower your heels while keeping your toes on the ground. After that, you can lift your toes while keeping your heels in contact with the ground.
A passive movement does not help, because it requires the contraction of the muscles to push the venous blood to the heart.
Movement. If you have to lie in bed for a long time due to surgery or other reasons, the earlier you move, the lower your risk of developing a blood clot.
Lifestyle change. Reduce weight, quit smoking and control blood pressure. Being overweight, smoking and high blood pressure increase the risk of deep vein thrombosis.
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