Deep Vein Thrombosis &
Superficial Phlebitis
Simply put, Deep Vein Thrombosis (DVT), is the formation of a blood clot in the large diameter, deep veins of the legs, as opposed to superficial phlebitis which also involves blood clot formation, but which is limited to superficial veins that lie just underneath the skin's surface. DVT can be a very serious condition that can be life-threatening. Approximately 600,000 new cases occur in the United States every year.
The large, deep veins of the legs lie below and inside the large muscles of the thigh and calf. When blood flow through these veins slows down (stasis), typically due to inactivity, injury or dehydration, blood will have a tendency to form clot within these veins. As clot forms, it will tend to block the vein and further slow down blood flow through the vein, resulting in further stasis and clot formation.
Superficial phlebitis, while involving clot that forms in the similar fashion, differs from DVT in one significant way. Clots formed in superficial veins are much less likely to break loose and travel to the lungs, resulting in a life-threatening pulmonary embolus (PE).
Symptoms of DVT can often be quite subtle, whereas with phlebitis where clotted superficial veins are often quite tender and painful. Symptoms of DVT can include:
- Leg fatigue or aching pain
- Calf or thigh tenderness
- Swelling and/or discoloration of the leg
- Sudden bulging of varicose veins where none were previously present
Certain risk factors make DVT more likely to occur in particular patient populations. Some know risk factors that make patients more likely to develop DVT include:
- Immobility, such as extended bed rest after injury or surgery
- Extensive travel with extended periods of sitting, such as a long plane trip (DVT has been referred to as “Economy Class Syndrome”.)
- Cancer
- Obesity
- Smoking
- Dehydration
- Injury to blood vessels or surrounding muscle
- History of prior DVT or family history of DVT
