Patient Education - Lung Cancer Program at UCLA
yourself about lung cancer:
Deep venous thrombosis
Deep venous thrombosis is a condition in which a blood clot forms in a vein that
is deep inside the body.
DVT; Blood clot in the legs
Deep venous thrombosis (DVT) mainly affects the veins in the lower leg and thigh.
A clot (thrombus) forms in the larger veins of the area. This clot can interfere
with blood flow, and it may break off and travel through the bloodstream (embolize).
The traveling blood clot (embolus) can lodge in the brain, lungs, heart, or other
area, severely damaging that organ.
Risks for DVT include prolonged sitting (such as on long plane or car trips) or
bedrest. It also may be caused by recent surgery (especially hip, knee, or female
reproductive organ surgery), fractures, childbirth within the last 6 months, and
the use of medications such as estrogen and birth control pills.
Risks also include overproduction of red blood cells in bone marrow (polycythemia
vera), cancerous (malignant) tumor, and having a condition in which the blood is
more likely to clot (hypercoagulability).
Deep venous thrombosis is most common in adults over age 60, but it can occur
in any age group.
- Leg pain in one leg
- Leg tenderness in one leg
- Swelling (edema) of one leg
- Increased warmth in one leg
- Changes in skin color (redness) in one leg
Exams and Tests
An exam may show a red, swollen, or tender leg.
The presence of deep venous thrombosis may be seen on:
- X-rays to show veins (venography) in the legs
- Doppler ultrasound exam of a limb
- Plethysmography of the legs
- D-dimer blood test
Many causes of increased clotting (hypercoagulability) can be found by these
- Antithrombin III, protein C, protein S
- Factor V Leiden
- Prothrombin 20210a mutation
- DIC screening
- Lupus anticoagulant and anticardiolipin antibodies
DVT treatment helps prevent a pulmonary embolus from forming and helps prevent
For years, the standard treatment has been a medication called heparin to stop
blood clots from forming (anticoagulant). Heparin is given through the vein. It results
in quick anticoagulation and it treats the clot. A person with DVT also may get an
oral medication called warfarin with the heparin.
Warfarin usually takes several days to fully work. Heparin is continued until
the warfarin has been fully effective for at least 24 hours. People will take warfarin
for about 6 months. Usually warfarin is started after heparin.
Because heparin is given continuously through a vein (IV), it requires a hospital
stay. However, newer forms of heparin known as low molecular-weight heparin (usually
a drug called enoxaparin) can sometimes be used. This heparin can be given by injection
once or twice a day to shorten or avoid the need for a hospital stay.
Warfarin causes an increase in the time it takes blood to clot, known as prothrombin
time (PT). A system called the International Normalized Ratio (INR) is used to report
the ability of the blood to clot properly. Doctors will adjust warfarin to keep the
INR between 2 and 3.
Most DVT's disappear without a problem, but they can recur. Some people may have
chronic pain and swelling in the leg, known as post phlebitic syndrome. Pulmonary
embolus is uncommon when DVT's are treated properly, but it can occur and can be
- Pulmonary embolus
- Post-phlebitic syndrome
When to Contact a Medical Professional
Call your health care provider if you have DVT-like symptoms.
Go to the emergency room or call the local emergency number (such as 911) if you
have DVT and you develop chest pain, difficulty breathing, fainting, loss of consciousness,
or other severe symptoms.
Doctors may prescribe anticoagulants to help prevent DVT in high-risk people
or those who are undergoing high-risk surgery. To help prevent DVT, move your legs
often during long plane trips, car trips, and other situations in which you are sitting
or lying down for long periods of time.
Review Date: 4/27/2007
Reviewed By: Rita Nanda, M.D., Department of Medicine, Section of Hematology/Oncology,
University of Chicago Medical Center, Chicago, IL. Review provided by VeriMed Healthcare
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