Deep vein thrombosis is the result of a clot that forms in the deep veins. Most commonly these occur in the leg but can also occur in the arms and rarely other areas of the body. It is quite simply coagulation of blood that blocks a deep artery and can result in a fatal condition known as pulmonary thromboembolism.
The biggest risk with DVT is that the clot breaks off, travels and cuts the supply of blood to the lungs, which can result in death.
Often there are no symptoms for DVT. It is a silent killer that can kill instantly should a clot break off and travel to the pulmonary arteries. When symptoms are present, they tend to consist of swelling, itching, soreness, itching and obvious engorgement of the superficial veins. Oftentimes, hotness in the affected area is the only sign, and, at times, there are no signs.
Air travel can cause DVT because sitting in a sedentary position on long-haul flights often cause clots to form. This is specifically true of those who have clotting disorders, take the contraceptive pill, are on HRT or sit in one position through an entire long haul flight.
Most airlines now have recommended exercises which are available in the back section of the inflight magazines. The exercises are aimed at moving the blood flow from the legs and are highly recommended for anyone on a long-haul flight.
Due to lack of leg room in economy seats on airplanes, the occurrence of DVT is most often dubbed "economy class syndrome." In 2006, a 26-year-old woman walked off a long-haul flight in Sydney and died almost minutes after starting to walk.
The cramped seating and the lack of the ability to move the legs is a major risk factor for this. It is not as common as people think but it does happen, thus, the current warnings and list of exercises in most inflight magazines.
If you have known clotting disorders that cause blood clots, you should always consult your physician before air travel, particularly long-haul flights. Risk factors include inborn clotting disorders; recent bed rest or chronic sitting, be it at a desk or due to recent surgery; use of hormone replacement therapy; use of contraceptive pills; smoking, especially with use of HRT or contraceptives, age 35 and over; excessive drinking; dehydration and sedentary positioning during a long haul flight. Pregnancy, mainly due to hormonal changes, is also a major risk factor.
If you do suffer any known risk factors, consult your physician, who may want to prescribe a blood thinner or other anti-clotting agents.
If you do not have any know risk factors, a few tips that work as mere preventative measures and are recommended include taking low-dose (325mg) aspirin and vitamin E, starting about a week before your flight. Drinking plenty of water during the flight is important so skip the wine and alcohol. Be sure you get up as often as you can, walking up and down the aisles every hour is a good rule of thumb as is standing every so often. Exercises, located in the inflight magazine, will show you appropriate foot rotations and how to move your feet up and down, which "pumps" the blood from the legs, thus not allowing the blood to pool and form clots. Stretching as often as you can, and compression stalkings--stalkings that can be bought in most pharmacies or medical supply stores--are also good preventative measures.
If you suspect you have a DVT, alert a flight attendant immediately and be sure that you are wheeled out of the airplane. The biggest risk factor with DVT is not the clot itself but its migration to the arteries in the lung, which can cause instantaneous death by traveling to the lungs and causing a pulmonary embolism. You should be seen immediately at the local hospital and insist on an ultrasound to ascertain whether you actually have a DVT, in which case it will be treated immediately.
