Home > Diseases and Conditions > Deep Venous Thrombosis
  • We are sorry, but NCBI web applications do not support your browser and may not function properly. More information

PubMed Health. A service of the National Library of Medicine, National Institutes of Health.

A.D.A.M. Medical Encyclopedia [Internet]. Atlanta (GA): A.D.A.M.; 2013.

A.D.A.M. Medical Encyclopedia.

Deep Venous Thrombosis

DVT; Blood clot in the legs; Thromboembolism; Post-phlebitic syndrome; Post-thrombotic syndrome

Last reviewed: January 1, 2013.

Deep venous thrombosis is a blood clot that forms in a vein deep inside a part of the body. It mainly affects the large veins in the lower leg and thigh.

Causes

DVTs are most common in adults over age 60. However, they can occur at any age. When a clot breaks off and moves through the bloodstream, this is called an embolism. An embolism can get stuck in the brain, lungs, heart, or other area, leading to severe damage.

Blood clots may form when something slows or changes the flow of blood in the veins. Risk factors include:

  • ·   A pacemaker catheter that has been passed through the vein in the groin
  • ·   Bed rest
  • ·   Family history of blood clots
  • ·   Fractures in the pelvis or legs
  • ·   Giving birth within the last 6 months
  • ·   Obesity
  • ·   Recent surgery (most commonly hip, knee, or female pelvic surgery)
  • ·   Too many blood cells being made by the bone marrow, causing the blood to be thicker than normal

Blood is more likely to clot in someone who has certain problems or disorders, such as:

  • Cancer
  • Certain autoimmune disorders, such as lupus
  • Cigarette smoking
  • Conditions in which you are more likely to develop blood clots
  • Taking estrogens or birth control pills (this risk is even higher if you smoke)

Sitting for long periods when traveling can increase the risk of DVTs. This is most likely when you also have one or more of the risk factors listed above.

Symptoms

DVT mainly affects the large veins in the lower leg and thigh, almost always on one side of the body. The clot can block blood flow and cause:

  • ·   Changes in skin color (redness)
  • ·   Leg pain
  • ·   Leg swelling (edema)
  • ·   Skin that feels warm to the touch

Exams and Tests

Your health care provider will perform a physical exam. The exam may show a red, swollen, or tender leg.

The two tests that are often done first to diagnose a DVT are:

  • ·   D-dimer blood test
  • ·   Doppler ultrasound exam of the legs 

Blood tests may be done to check if you have an increased chance of blood clotting, including:

  • Activated protein C resistance (checks for the Factor V Leiden mutation)
  • Antiphospholipid antibodies
  • Genetic testing to look for mutations that make you more likely to develop blood clots, such as the prothrombin G20210A mutation
  • Protein C and protein S levels

Treatment

Your doctor will give you medicine to thin your blood (called an anticoagulant). This will keep more clots from forming or old ones from getting bigger. These drugs do not dissolve clots you already have—that is accomplished by your body’s natural blood system.

Heparin is usually the first drug you will receive.

  • If heparin is given through a vein (IV), you must stay in the hospital.
  • Newer forms of heparin can be given by injection under your skin once or twice a day. You may not need to stay in the hospital as long, or at all, if you are prescribed this newer form of heparin.

Depending on your medical history, fondaparinux may be recommended by your doctor as an alternative to heparin.

A drug called warfarin (Coumadin) is usually started along with heparin.

  • Warfarin is taken by mouth. It takes several days to fully work.
  • Heparin is not stopped until the warfarin has been at the right dose for at least 2 days.
  • You will most likely take warfarin for at least 3 months. Some people must take it longer, or even for the rest of their lives, depending on their risk for another clot.

When you are taking warfarin, you are more likely to bleed, even from activities you have always done. If you are taking warfarin at home:

  • Take the medicine just the way your doctor prescribed it
  • Ask the doctor what to do if you miss a dose
  • Get blood tests as advised by your doctor to make sure you are taking the right dose
  • Learn how to take other medicines and when to eat
  • Find out how to watch for problems caused by warfarin

Newer blood thinning medicines that are taken by mouth are being developed. Your doctor may recommend one of these for you.

You will be given a pressure stocking to wear on your leg or legs, along with other discharge instructions. A pressure stocking improves blood flow in your legs, and reduces your risk for complications from blood clots. It is important to wear it every day.

In rare cases, you may need surgery if medicines do not work. Surgery may involve:

  • Placing a filter in the body's largest vein to prevent blood clots from traveling to the lungs
  • Removing a large blood clot from the vein or injecting clot-busting medicines

Outlook (Prognosis)

Many DVTs disappear without a problem, but they can return. Some people may have long-term pain and swelling in the leg called post-phlebitic syndrome.

You may also have pain and changes in skin color. These symptoms can appear right away, or you may not develop them for 1 or more years afterward. Wearing tight (compression) stockings during and after the DVT may help prevent this problem.

Blood clots in the thigh are more likely to break off and travel to the lungs (pulmonary embolus, or PE) than blood clots in the lower leg or other parts of the body.

When to Contact a Medical Professional

Call your health care provider if you have symptoms of DVT.

Go to the emergency room or call the local emergency number (such as 911) if you have DVT and you develop:

Prevention

Some things you can do to prevent deep vein thrombosis include:

  • Wear the pressure stockings your doctor prescribed.
  • Moving 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.
  • Take blood thinning medicines your doctor prescribes.
  • Don't smoke. Talk to your doctor if you need help quitting smoking.

References

  1. Ginsberg J. Peripheral venous disease. In: Goldman L, Schafer AI, eds. Cecil Medicine. 24th ed. Philadelphia, Pa: Saunders Elsevier; 2011:chap 81.
  2. Guyatt GH, Akl EA, Crowther M, et al. Executive Summary: Antithrombotic Therapy and Prevention of Thrombosis. 9th ed. American College of Chest Physicians Evidence-Based Clinical Practice Guidelines. Chest. 2012;141(2 suppl):7s-47s.  [PMC free article: PMC3278060] [PubMed: 22315257]
  3. Snow V, Qaseem A, Barry P, et al. Management of venous thromboembolism: a clinical practice guideline from the American College of Physicians and the American Academy of Family Physicians. Ann Intern Med. 2007;146(3):204-210. [PubMed: 17261857]

Review Date: 1/1/2013.

Reviewed by: David C. Dugdale, III, MD, Professor of Medicine, Division of General Medicine, Department of Medicine, University of Washington School of Medicine. Also reviewed by A.D.A.M. Health Solutions, Ebix, Inc., Editorial Team: David Zieve, MD, MHA, Bethanne Black, and Nissi Wang.

A.D.A.M., Inc. is accredited by URAC, also known as the American Accreditation HealthCare Commission (www.urac.org). URAC's accreditation program is an independent audit to verify that A.D.A.M. follows rigorous standards of quality and accountability. A.D.A.M. is among the first to achieve this important distinction for online health information and services. Learn more about A.D.A.M.'s editorial policy, editorial process and privacy policy. A.D.A.M. is also a founding member of Hi-Ethics and subscribes to the principles of the Health on the Net Foundation (www.hon.ch).

The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed medical professional should be consulted for diagnosis and treatment of any and all medical conditions. Call 911 for all medical emergencies. Links to other sites are provided for information only — they do not constitute endorsementscof those other sites. © 1997–2011 A.D.A.M., Inc. Any duplication or distribution of the information contained herein is strictly prohibited.

Copyright © 2013, A.D.A.M., Inc.

A.D.A.M., Inc. is accredited by URAC, also known as the American Accreditation HealthCare Commission (www.urac.org). URAC's accreditation program is an independent audit to verify that A.D.A.M. follows rigorous standards of quality and accountability. A.D.A.M. is among the first to achieve this important distinction for online health information and services. Learn more about A.D.A.M.'s editorial policy, editorial process and privacy policy. A.D.A.M. is also a founding member of Hi-Ethics and subscribes to the principles of the Health on the Net Foundation (www.hon.ch).

The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed medical professional should be consulted for diagnosis and treatment of any and all medical conditions. Call 911 for all medical emergencies. Links to other sites are provided for information only — they do not constitute endorsementscof those other sites. © 1997–2011 A.D.A.M., Inc. Any duplication or distribution of the information contained herein is strictly prohibited.

Copyright © 2013, A.D.A.M., Inc.

What works?

  • Blood thinners for the prevention of blood clots in children with central venous lines
    Over the last 10 years, the number of children found to have blood clots in their blood vessels, called veins, has become more common. As blood clots can either block these vessels and change their normal blood flow or shower pieces into other veins placed in important organs, serious health problems including death can occur. Venous clots are usually found in children with plastic tubes placed inside their blood vessels, called central lines, which are inserted to help or save the patient's life. However, these lines can also cause blood clots. We do not know if giving a medication to protect against blood clots, called an anticoagulant or low molecular weight heparin (LMWH), would protect against the clots. Therefore, we looked at all the research in children with central lines who received, or not, LMWH and only found one study with a total of 186 participants. This study did not have enough participants to show if this medication protects children with central lines from getting blood clots. The study also did not show that children on LMWH, at the doses given, experience too much bleeding because of its use. The included study did not report any additional adverse events. There were two deaths within the study in the standard care arm, and neither were due to a blood clot. Future studies looking at the role of this medication (LMWH) and if it protects children with central venous lines from getting blood clots are needed.
See all (70) ...

Figures

  • Deep venous thrombosis, iliofemoral.
    Deep veins.
    Venous blood clot.
    Deep veins.

PubMed Health Blog...

read all...

MedlinePlus.gov links to free, reliable, up-to-date health information from the National Institutes of Health (NIH) and other trusted health organizations.

Recent Activity

Your browsing activity is empty.

Activity recording is turned off.

Turn recording back on

See more...