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Deep vein thrombosis: What you need to know

  • Published
  • Military Health System Communications Office
Military Health System beneficiary Jamia Bailey plays three sports at Yokota High School in Fussa, Japan. She spends long hours traveling with her teammates to competitions at schools eight and even 10 hours away. When her left leg became swollen and painful one morning during class, a trip to the school nurse’s office and then to the urgent care clinic on Yokota Air Base schooled Bailey on deep vein thrombosis, or DVT.

DVT is a blood clot that forms in a vein deep inside the body. It usually occurs in the lower leg, thigh, or pelvis.

“Blood clots naturally form in our body after injury to prevent blood loss through the blood vessel wall,” said U.S. Air Force Col. Jay Sampson, a board-certified vascular surgeon at Lackland Air Force Base in San Antonio.

“We also have a natural process to stop clot formation and then to break down the clot,” he said. “DVT occurs when something goes wrong with this clotting process.”

As many as 900,000 Americans may be affected by DVT each year, according to the Centers for Disease Control and Prevention. Of those, the CDC said, about half will have long-term complications, including swelling and pain. Additionally, about 33 percent will have a DVT recurrence within 10 years.

DVT is particularly dangerous if part of the clot breaks off and travels through the bloodstream to the lungs. This causes a pulmonary embolism, or PE, which prevents blood from reaching the lungs. According to the CDC, from 60,000 to 100,000 people die each year from PE.

“Numerous risk factors can help identify who might be at risk for DVT,” Sampson said. “But in the medical community, we tend to think of it as, everyone’s at risk.”

Risk factors include being obese, older, or confined to bed because of illness or disease, Sampson said. But even young and fit people can be at risk when they’re immobile for long periods of time. NBC television journalist David Bloom was 39 when he died of PE in April 2003 while covering the Iraq War. Bloom had spent long hours inside cramped armored vehicles.

Pregnant women up to six weeks after childbirth, and women who take oral contraceptives that include estrogen, also have an increased risk of DVT, Sampson said. Changes in hormone levels and blood composition may affect the normal clotting process. Also, blood flow in the legs may be reduced because of the fetus pressing on the veins.

Swelling and pain are two symptoms of DVT. But some people don’t experience any symptoms at all, Sampson said.

The signs and symptoms of PE include difficulty breathing, chest pain, and coughing up blood. But sudden death, like Bloom’s, is the first symptom in about 25 percent of people with PE, according to the CDC.

Bailey went to Tripler Army Medical Center in Hawaii for treatment with dad James, a retired Navy senior chief petty officer, and mom Pia, a Department of Defense Education Activity elementary school teacher.

“Jamia was predisposed to getting DVT because she has May-Thurner syndrome, and the long periods of immobility during bus rides were a contributing factor,” said Dr. Brian Ching, an interventional radiologist at Tripler.

May-Thurner is a rare condition in which an artery compresses a vein in the pelvis. Bailey had minor surgery to remove the blood clots; a stent was inserted into the compressed vein to keep it open. She’s now taking a blood thinner to reduce the risk of DVT recurring.

“A blood thinner prevents the clot from getting bigger,” Sampson said. “It also stabilizes the clot to reduce the risk of it traveling to the pulmonary artery. That’s the pulmonary embolism we worry about.”

Bailey said she can’t play soccer while she’s taking a blood thinner because any head trauma could cause bleeding in the brain. Otherwise, she’s resumed her normal activities. Her goal is to play basketball next year for Chaminade University in Hawaii.

“I really appreciate the doctors and nurses who helped me get through that rough part of my life,” she said.

Sampson and other experts offer the following tips to reduce risk of DVT:

 Move around as soon as recommended after being confined to bed for surgery, illness, or injury.

  • Stretch your legs every few hours during long periods of immobility, including during air travel. Wear loose-fitting clothing and perhaps even compression socks, which prevent pooling of blood in the legs.
  • Seek medical help immediately for swelling and pain in the legs or arms. “The next step would be an ultrasound test to diagnose,” Sampson said.