FAQs: What is deep vein thrombosis?
3/12/2020 by Thomas Jaeger, MD
Every once in a while, deep vein thrombosis (DVT) makes the news when someone develops it on an airplane, often with serious effects on their health. But what is it and how can you avoid developing it?
What is deep vein thrombosis?
DVT is a condition where a clot forms in the veins of our legs, deep inside the muscles. It can develop if you have certain medical conditions that affect how your blood clots. DVT can also happen if you don't move for a long time, such as after surgery or an accident, when you're confined to bed or sit too long when flying or driving.
This condition can be very serious because blood clots in your veins can break loose, travel through your bloodstream, lodge in your lungs and block blood flow, causing a pulmonary embolism. It's not all that common, though, affecting only about 3% of individuals.
DVT can be confused with other conditions, including superficial thrombophlebitis and even a strain of your calf muscle. With superficial thrombophlebitis, the area has tenderness, often redness and warmth just under the surface of the skin. While the superficial clots are more obvious, they're much less serious than clots with DVT.
What are the symptoms?
The symptoms of DVT can be subtle. One leg, but not both, may swell over the course of a few days. This swelling is more prominent than what we all experience to some extent as the day progresses. There may be some discomfort, but it's harder to pinpoint.
How is DVT diagnosed?
If someone has new, unexplained pain or swelling of a single leg, DVT is a possibility. An evaluation should be scheduled promptly, within a day, if possible. Determining the cause of leg symptoms, whether pain or swelling, requires direct examination. This exam usually includes diagnostic testing, typically an ultrasound. In some instances, a clot is discovered as a result of testing done for other reasons.
What is the treatment?
In almost all cases, treatment of DVT requires blood-thinning medication, which falls into two categories:
- Newer blood thinners. These are convenient, don't require injections and are somewhat safer, but they can be expensive.
- Warfarin, pill form. Warfarin is still used routinely but it requires five or more days of heparin injections, as well as regular testing to monitor effectiveness. Even patients consistently taking the same dose of warfarin might have thinner and thicker clotting depending on diet, acute illness or other medications, so warfarin requires regular monitoring. Monitoring is done through the Primary Care in Rochester Anticoagulation Clinic pharmacy and nursing staff.
What happens after treatment?
Once you receive treatment for DVT, you'll need to:
- Check with your doctor regularly to see if your treatment needs to be modified. If you're taking warfarin (Coumadin®, Jantoven®), you'll need a blood test to see how well your blood is clotting.
- Take your blood thinners as directed. If you've had DVT, you'll be on blood thinners for at least three to six months.
- Watch for excessive bleeding, which can be a side effect of taking blood thinners. Talk to your doctor about activities that could cause you to bruise or get cut, since even a minor injury could become serious if you're taking blood thinners.
- Move. If you've been on bed rest because of surgery or other factors, the sooner you get moving, the less likely blood clots will develop.
How can DVT be prevented?
The best treatment for DVT is preventing it from occurring. Here are some things you can do:
- Avoid sitting still.
- If you've had surgery or been on bed rest for other reasons, try to get moving as soon as possible.
- If you're sitting for a while, don't cross your legs, which can hamper blood flow.
- If you're traveling a long distance by car, stop every hour or so and walk around.
- If you're on a plane, stand or walk occasionally. If you can't do that, exercise your lower legs. Try raising and lowering your heels while keeping your toes on the floor, then raising your toes with your heels on the floor.
- Make lifestyle changes. Lose weight and quit smoking.
- Exercise. Regular exercise lowers your risk of blood clots, which is especially important for people who sit a lot or travel frequently.
Dr. Thomas Jaeger is a consultant in Primary Care in Rochester/Kasson's Division of Community Internal Medicine, and is the Medical Director of the Primary Care Anticoagulation Clinic.