Complications and Management of DVT

Complications of DVT

Pulmonary Embolism
The most serious complication of DVT occurs when a clot becomes dislodged from a vein, travels to the lung, and blocks or partially blocks the pulmonary artery leading from the heart to the lungs. This condition is called pulmonary embolism.

This short-term complication is potentially life-threatening and occurs in about 10% of patients with acute DVT events.

If the clot is small, only one or more portions of the lung may be deprived of blood and damaged. This condition can result in:

• Shortness of breath

• Chest pain with breathing

• Bloody sputum (material coughed up from the lungs)

If a blood clot blocks the pulmonary artery, pulmonary embolism can be fatal due to the inability of blood to circulate through the lungs.
Vigorous treatment is immediately begun with blood-thinning drugs, oxygen and other medications depending on the situation.

Multiple and repeated emboli can lead to chronic impairment of blood circulation through the lungs and cause a form of heart failure.

Post-Thrombotic Syndrome
Post-thrombotic syndrome is the name used to describe the long-term effects that can occur after you have had a venous thrombosis of the deep veins of the leg. In many people who have had a DVT, the thrombus leaves scars within the vein. This scarring can damage the valves and narrow the diameter of the veins.

If the valves in the deep veins are damaged then blood runs in the wrong direction, towards the ankle. This puts extra pressure on the ankle's blood vessels which means the leg can swell. Many people with this problem of incompetent deep veins ( valves that do not work) have pain in their leg when they stand up. The pain can get worse as the day continues. They only get relief when the lie down again.

The scarring of the veins can narrow their diameter. This means the calf muscle can only pump small amounts of blood out of the leg. This makes it difficult to drain the blood from the leg.

When the incompetent valves and failed calf pump are combined, the leg can become increasingly swollen and painful.Skin of the affected area appears thickened and glossy as well. Another possibility is an ulcer of the skin which can occur months to years after the blood clot. This condition is the Post-Thrombotic or Post-Phlebitic Syndrome.

Post-thrombotic syndrome can cause serious long-term ill health, poor quality of life, and increased costs for the patient and the healthcare system. Post thrombotic syndrome is common in people who have had thrombosis, whether they are young or old. Generally, 1 out of 3 people who have had thrombosis in the legs will develop some post-thrombotic symptoms within 5 years. People who have thrombosis more than once (recurrent thrombosis) are at higher risk for post-thrombotic syndrome. Thrombosis can go unnoticed, so it is sometimes possible to have post-thrombotic syndrome without being diagnosed with thrombosis first.

How Is Deep Vein Thrombosis Treated?

Treatment of DVT is aimed at:

• Easing symptoms

• Preventing worsening of the clot

• Preventing the clot from traveling to the lungs

Treatment usually requires hospitalization, primarily to facilitate monitoring of medications. Because DVT occurs in post-surgical patients, however, the person might already be in the hospital when DVT is diagnosed.

Deep vein thrombosis must be treated promptly. Once the diagnosis is confirmed, the individual is kept in bed with the foot of the bed elevated.

Bed rest. Individuals with DVT usually require bed rest until symptoms are relieved. The leg should be elevated to a position above the heart to reduce swelling (the foot of the bed is elevated about six inches to achieve this). Moist heat may be applied to the affected region to relieve pain.

Compression stockings. Physicians frequently recommend that people who have DVT wear compression stockings (also called support hose) to reduce symptoms. Compression stockings improve circulation by providing a graduated pressure on the leg to help return the venous blood to the heart.

Blood-thinning drugs. Treatment with anticoagulants (commonly known as blood thinners) is required in most cases of DVT. The anticoagulant drugs heparin and warfarin are used primarily to prevent the formation of new clots, and, thus, reduce the chance of pulmonary embolism.

Heparin is the anticoagulant drug of first choice. It must be administered intravenously (an injection made directly into a vein).

Warfarin (also called coumarin) is taken by mouth.

Treatment with heparin normally lasts seven to 14 days. Treatment with warfarin is usually continued from two to six months, depending on the age of the person, the severity of the DVT, and whether risk factors are present.

Warfarin usually takes several days to become fully effective, so heparin is continued until the warfarin has been fully effective for at least 24 hours. In almost all circumstances, warfarin is started only after heparin has been stared.

Pregnant mother should not take warfarin as it can cross the placenta and cause birth defect.

Patient should also consult the doctor before taking other drug such as aspirin together with anticoagulant drug due to additive effect and can cause excessive bleeding.
Blood tests will check how well the medicine is working. You should call your doctor right away if you are taking warfarin or heparin and have easy bruising or bleeding.

Clot-busting medication. Drugs called thrombolytic agents (clot-dissolving medications) are used to help dissolve existing clots and reopen clogged veins. The most commonly used thrombolytic agents are urokinase, streptokinase, and recombinant tissue plasminogen activator (rt-PA).

The best results occur when this treatment is given to people who have had DVT for less than 48 hours.

When effective, the clot usually breaks up within 24 to 48 hours.

Thrombolytic agents can also cause internal and external bleeding, and require careful monitoring. Treatment with thrombolytic agents usually lasts for only 24 to 72 hours.

Surgery. If an embolus develops, surgery may be necessary to prevent the spread of the clot to the lung. Surgery, however, is performed only as a last resort.

Surgery for complications resulting from DVT involves the insertion of a filter into a large blood vessel to trap any blood clots headed toward the lungs. The filter allows blood to flow through it normally, but traps the traveling clots. The procedure is called vena cava interruption because the filter is placed in the inferior vena cava, the large vein in the pelvic area that receives the blood returning from the deep femoral (thigh) veins.

The most severe cases of DVT may require the surgical removal of the blood clot from the vein, a procedure known as venous thrombectomy. The patient is given anticoagulant therapy with heparin during the surgery, and warfarin for a period of at least six weeks to three months following the operation.


Reference:
http://www.ehealthmd.com/library/dvt/DVT_complications.html
http://www.venous-info.com/handbook/hbk02c.html
http://www.swindon-marlborough.nhs.uk/departments/anticoag/pts.htm
http://bdb.org.uk/Post%20thrombotic%20syndrome.htm
http://www.cardiosource.com/ExpertOpinions/Programhlts/interviewDetail.asp?interviewID=211
http://bdb.org.uk/Post%20thrombotic%20syndrome.htm

Video:
http://www.nhlbi.nih.gov/health/dci/Diseases/Dvt/DVT_WhatIs.html
http://www.legalpointer.com/displaymonograph.php?MID=148

Contributed by
Lawrence Oh