Long Distance Travel Puts Traveler At Risk of DVT
Deep-vein thrombosis (DVT) is a not uncommon medical condition which can have serious consequences including death. As many as 2 million Americans will suffer from DVT each year. Of these, approximately 300,000 will result in death as the DVT goes on to cause a pulmonary embolus (PE).
Yesterday an article was published in the Annals of Internal Medicine warning of one cause of DVT - long flights. The researches report a threefold increase in risk for DVT with long stretches of travel which for most implies flights. It can also be long drives without stops to walk around.
Divay Chandra, MD and colleagues noted an increase of 18% higher risk of DVT with each additional 2 hours in travel duration. This included travel of any kind – flight, train, car. With air travel, the increased risk was 26%.
The most serious complication of DVT is pulmonary embolism (PE). It occurs when the blood clot which has formed in the leg breaks loose and travels to the lungs. There is blocks blood flow in branches of the pulmonary circulation making it difficult for the lungs to oxygenate blood for the body. An estimated 300,000 deaths occur annually from PE.
Symptoms include swelling, pain, tenderness, discoloration or redness of the affected area. The skin may be warm to the touch. However, as many as half of all DVT episodes produce minimal symptoms or are completely "silent."
Besides long travel, other risks factors include age over 40 years, cancer, obesity, smoking, use of birth control, surgery, and family or personal history of DVT.
Preventive techniques for long travel include staying hydrated, flexing your calf muscles, and if possible getting up and walking around. Proper hydration can be done by drinking a glass of water every couple of hours. Avoid excess coffee or alcohol as they may dehydrate you. If you are at moderate or high risk, consider wearing below-the-knee compression stockings during travel.
Chandra D, et al "Travel and risk for venous thromboembolism" Ann Intern Med 2009; 151(3).