What is Deep Vein Thrombosis (DVT)?
Deep Vein Thrombosis is the technical name for one or more blood clots in veins deep in your body. They usually occur in the calves or thighs, less often in the arms. A sub-massive blood clot is usually not visible on the surface.
- swelling in a leg or arm for no apparent reason
- pain or tenderness in the leg, most often when standing or walking
- red or oddly colored skin in the painful area
- warmth in the painful area
Even a sub-massive blood clot is a dangerous situation. A DVT can block blood flow to the leg and foot, causing major damage. A free-floating clot, called an embolus, can travel with the blood to the heart or lungs, where it can cause damage or even sudden death.
Who is most likely to get a DVT?
- people over 60
- cancer patients
- someone who has broken a bone
- surgical patients
- bedridden or very inactive people
- anyone with certain heart conditions
- pregnant women and those using hormonal birth control
- people with a previous history of chronic DVT
If I suspect a blood clot, I order an ultrasound for accurate diagnosis. This often includes imaging the unaffected limb as a comparison. Sometimes these tests deliver surprises, such as a patient who had not only the expected clots in the post-surgical leg, but a fairly large one in the other thigh as well!
Compression Stockings: Why and How They Work
One of the first prescriptions I give anyone diagnosed with a DVT is one for compression stockings. They’re a simple mechanical way to restore circulation to the damaged area, giving a boost to the body’s own efforts at circulating the blood.
Compression stockings are tightly knit nylon stockings that come in lengths from knee-high to thigh-high. Pressure from the stockings forces the blood flow upwards from the feet, giving a boost to the circulation in the leg. When the blood is moving, it’s much less likely to form clots.
The amount of compression in the stockings is measured in mm/hg. Higher numbers put more pressure on the area. Your doctor will prescribe or recommend the amount of pressure you need based on your individual situation.
Types of Compression Stockings
Support pantyhose are actually a light form of compression stockings. They’re excellent for someone who doesn’t usually have circulation problems but is facing a long period of immobility, such as extended travel.
Over-the-counter compression stockings are sold in pharmacies and health supply stores. They offer somewhat more compression than pantyhose and come in a couple of colors, many sizes, and sometimes a choice of thigh-high or knee-high. These, too, are useful in travel situations and can be worn without a prescription.
Prescription compression stockings are the kind I usually recommend for patients with DVTs. They must be specially fitted and usually need to be bought from a health supply store. Jobst, Solaris, Medi, and Juzo are popular brands that work well.
When Do You Use Compression Stockings?
I always suggest putting compression stockings on before getting out of bed in the morning and leaving them on till bedtime. They really should be worn all your waking hours for the best results!
Some research has been done on use of compression stockings for a day or two before scheduled surgery to prevent blood clots. They’ve been found to be effective in small studies, but more research would be useful to see whether this should be a universal practice.
Once compression stockings are prescribed and fitted, they should be worn every day, usually for about six months. Sometimes if the clots were the result of a specific situation such as a surgery, they can be discontinued sooner.
If you have a history of chronic DVT, compression stockings will be the norm for you. Find a brand you like and plan on making them a part of your life.
What If Compression Stockings Aren’t Enough?
Compression stockings alone don’t always work to prevent more blood clots from forming, even when they’re used correctly. In that case, chemical blood thinners have to be used. Those lower the platelet count, making the blood cells less “sticky”.
Blood thinners range from simple aspirin to strong anticoagulants such as Warfarin. They can be taken as pills, in an IV, or injected under the skin. If blood thinners are needed, they typically are employed for about six months.
Blood thiners don’t destroy the clots, as most people think. The body gradually dissolves the old clots, but the less dense blood prevents new clots from forming.
It’s important for prothrombin levels in your blood to be monitored when you’re using blood thinners. The dose can be adjusted for best effect, just enough to prevent clots, but not so much that hazardous bleeding occurs.
A deep vein thrombosis is a serious situation. Proper use of compression stockings can go a long way toward dealing with them. If extra help is needed, blood thinners enter the picture. They don’t change the need for compression stockings, but a combination of the two is almost always successful!