Blood clots, mainly in the legs, also known as deep vein thrombosis (DVT), are a major health risk for older Americans. They can lead to serious health complications and potentially even death. Learning to recognize risk factors for DVT as well as the warning signs that you may have developed one is vitally important. Equally as important is understanding the things you can do to minimize your risk.

 Risk factors include prolonged periods of immobility such as hospitalization or broken bones, as well as a long-distance travel, particularly air travel. Prevention of DVTs is the reasons many hospitalized patients are put on anticoagulants (blood thinners) either by mouth or by shots in their abdomen. Other risk factors include smoking, obesity, orthopedic surgery, use of oral contraceptives or hormone replacement therapy, cancer, heart failure and age greater than 65.

DVTs form in the deep veins of the legs. These are the large veins that communicate directly with the lungs. When small pieces of blood clot break off, they can travel to the lungs and cause what is known as a pulmonary embolism (PE). This can be a major threat to life and may require long term treatment with anticoagulation medicines. While not every DVT leads to a PE, It is important to recognize the warning signs that you may have a DVT and even more important to understand how to go about preventing them.

First, we should recognize the difference between DVTs and their unattractive cousins, varicose veins. We’ve all seen varicose veins and many of us have them. They are unsightly and sometimes can even be painful. However, they do not present the same risk to health and life as DVTs. Varicose veins are superficial veins and even if clots are formed in them, they cannot make it to your lungs.

There are several things to look for that may indicate you have a DVT. The most common is unilateral calf swelling where one leg is about two inches larger than the other measured at a point about four inches below the knee. Since most of us don’t carry a tape measure, be concerned if one leg looks larger than the other. Swelling may also consist of an entire leg. Occasionally both legs may be swollen but that is unusual. The swelling is often what is called pitting edema. In pitting edema, you can press your finger into the swollen area and remove it and a dent remains. Calf tenderness in the swollen leg may also be indicative of a DVT. If the swelling is significant, numbness may also be present. Pain with walking is also common and, in some cases, the swollen leg feels warm to the touch. Some of the same symptoms can be found in complications of varicose veins known superficial thrombophlebitis, a painful but not usually life-threatening condition. If you have any of the above symptoms you should immediately visit your family physician or other medical provider to ensure that a DVT is not missed.

And now, the most important part, what can you do to keep from getting a DVT? The easy things first. Wear loose clothes, drink plenty of water, and avoid anything with alcohol or caffeine. The best way to prevent a DVT is to get up and walk every couple of hours. Of course, this is easier said than done on a transcontinental or international flight. So, let’s look at a few things that can be done in your airline seat, or even in your car, to reduce your risk.

You want to exercise your legs while you’re seated. First you can raise and lower your heels while keeping your toes on the floor. You can also raise and lower your toes while keeping your heels on the floor. You can tighten and release your calf muscles. A little more advanced exercise is to lift your feet off the floor and twirl them around as if you’re trying to draw circles with your toes. If you have sufficient room in your airline seat you can try extending your knees or doing knee lifts. For most of us though there just isn’t enough room in an airline seat for doing these last two. You should do these exercises for about 30 to 40 seconds each and they should be repeated about every 30 to 40 minutes. This may not eliminate your risk of developing a blood clot but will certainly reduce it. Additionally, while there is some evidence to suggest that aspirin may reduce the risk of developing a blood clot, there are currently no specific guidelines for its use in prevention of DVTs and aspirin therapy does have some associated risk of bleeding. Be sure and contact your family doctor before starting aspirin therapy to prevent DVTs.

If you have any concern at all, seek medical assistance. It is better to be safe than to miss a DVT. Finally, safe travels.