Deep Vein Thrombosis
(DVT, Blood Clot in the Legs)

Heart Disease (Coronary Artery Disease) Slideshow

Medical Author: Benjamin C. Wedro, MD, FAAEM
Medical Editor: Melissa Conrad Stöppler, MD

• Introduction to deep vein thrombosis
• What are the causes of deep vein thrombosis?
• What are the symptoms of deep vein thrombosis?
• When should I seek medical care for deep vein thrombosis?
• How is deep vein thrombosis diagnosed?
• What is the treatment for deep vein thrombosis?
• What are the complications of deep vein thrombosis?
• Can deep vein thrombosis be prevented?
• Patient Discussions: Deep Vein Thrombosis - Symptoms Experienced

How Pie Prevents Blood Clots Medical Author: Benjamin C. Wedro, MD, FAAEM Medical Editor: Melissa Conrad Stöppler, MD This weekend, as I drove the 5 hours to the north Wisconsin woods, I reminded myself of advice I give to my patients: remember to get out of the car and move around. It's also why, buried deep in the recesses of the in flight magazine, somewhere between the movie grid and the duty free opportunities, hides a warning that staying still in an airplane seat for a prolonged time can cause blood clots. And while the magazine recommends moving around the cabin and stretching, the flight attendants tend to want to keep you in your seat. Blood does wonderful things like carrying oxygen, cleaning waste products, and delivering cells and chemicals to fight infection. But mess up its environment and blood can cause all sorts of problems. Blood cells get pushed by the heart to the far recesses of the body, but returns from the fingers, toes, arms and legs in veins that are milked by the routine contractions of the muscles that surround them. As you walk, blood gets pushed back to the heart; as you type, the muscles of your fingers and hands do the work to get the blood back. Without that muscle movement, blood stagnates and has a tendency to clot... Read more about preventing deep vein thrombosis and pulmonary embolism from Dr. Wedro » Top Searched Deep Vein Thrombosis (DVT) and Pulmonary Embolism Terms: dvt symptoms, prophylaxis, dvt treatment, COPD pulmonary embolism, dvt prevention, dvt stockings, causes of dvt, aspirin, pregnancy, flying

Introduction to deep vein thrombosis (DVT)

Arteries have thin muscles within their walls to be able to withstand the pressure of the heart pumping blood to the far reaches of the body. Veins don't have a significant muscle lining, and there is nothing pumping blood back to the heart except physiology. Blood returns to the heart because the body's large muscles squeeze the veins as they contract in their normal activity of moving the body. The normal activities of moving the body returns the blood back to the heart.

There are two types of veins in the leg; superficial veins and deep veins. Superficial veins lie just below the skin and are easily seen on the surface. Deep veins, as their name implies, are located deep within the muscles of the leg. Blood flows from the superficial veins into the deep venous system through small perforator veins. Superficial and perforator veins have one-way valves within them that allow blood to flow only in the direction of the heart when the veins are squeezed.

A blood clot (thrombus) in the deep venous system of the leg is not dangerous in itself. The situation becomes life-threatening when a piece of the blood clot breaks off (embolus, pleural=emboli), travels downstream through the heart into the pulmonary circulation system, and becomes lodged in the lung. Diagnosis and treatment of a deep venous thrombosis (DVT) is meant to prevent pulmonary embolism.

Clots in the superficial veins do not pose a danger of causing pulmonary emboli because the perforator vein valves act as a sieve to prevent clots from entering the deep venous system. They are usually not at risk of causing pulmonary embolism.

How Pie Prevents Blood Clots Medical Author: Benjamin C. Wedro, MD, FAAEM Medical Editor: Melissa Conrad Stöppler, MD This weekend, as I drove the 5 hours to the north Wisconsin woods, I reminded myself of advice I give to my patients: remember to get out of the car and move around. It's also why, buried deep in the recesses of the in flight magazine, somewhere between the movie grid and the duty free opportunities, hides a warning that staying still in an airplane seat for a prolonged time can cause blood clots. And while the magazine recommends moving around the cabin and stretching, the flight attendants tend to want to keep you in your seat. Blood does wonderful things like carrying oxygen, cleaning waste products, and delivering cells and chemicals to fight infection. But mess up its environment and blood can cause all sorts of problems. Blood cells get pushed by the heart to the far recesses of the body, but returns from the fingers, toes, arms and legs in veins that are milked by the routine contractions of the muscles that surround them. As you walk, blood gets pushed back to the heart; as you type, the muscles of your fingers and hands do the work to get the blood back. Without that muscle movement, blood stagnates and has a tendency to clot... Read more about preventing deep vein thrombosis and pulmonary embolism from Dr. Wedro » Top Searched Deep Vein Thrombosis (DVT) and Pulmonary Embolism Terms: dvt symptoms, prophylaxis, dvt treatment, COPD pulmonary embolism, dvt prevention, dvt stockings, causes of dvt, aspirin, pregnancy, flying

What are the causes of deep vein thrombosis?

Blood is meant to flow; if it becomes stagnant there is a potential for it to clot. The blood in veins is constantly forming microscopic clots that are routinely broken down by the body. If the balance of clot formation and resolution is altered, significant clotting can occur. A thrombus can form if one, or a combination of the following situations is present:

Immobility

• Prolonged travel and sitting, such as long airplane flights ("economy class syndrome"), car, or train travel
  
  
• Hospitalization
  
  
• Surgery
  
  
• Trauma to the lower leg with or without surgery or casting
  
  
• Pregnancy, including 6-8 weeks post partum
  
  
• Obesity

Hypercoagulability (coagulation of blood faster than usual)

• Medications (for example, birth control pills, estrogen)
  
  
• Smoking
  
  
• Genetic predisposition
  
  
• Polycythemia (increased number of red blood cells)
  
  
• Cancer

Trauma to the vein

• Fracture to the leg
  
  
• Bruised leg
  
  
• Complication of an invasive procedure of the vein

Deep Vein Thrombosis - Symptoms Experienced

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