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Avoiding Blood Clots When You Travel

by Russell Eaton
www.airtravelsurvival.com

Many travel experts say that DVT (Deep Vein Thrombosis) is not specifically linked to flying and can occur anywhere people are immobile for lengthy periods. This is indeed an argument often used by the airline industry, and is a myth that is even held by many doctors. As explained in my book 'Air Travel Survival' (www.airtravelsurvival.com) there is a wide-held misconception that a long journey on a bus, car or train is no different to a long journey on a plane if the seating is equally cramped. This is not so. In the context of blood clots, air travel is fundamentally different to any other kind of travel because of dehydration.

Air travel dehydration (i.e. insufficient water in the body) is caused by not drinking sufficient water during the journey, by drinking alcohol, tea and coffee instead of water, and by super-dry cabin air.

So unlike a bus, car or train journey, when you travel by air you are much more likely to suffer dehydration, and this in turn increases the danger of blood clots. This is so for four reasons:

i. BLOOD THICKENING. Dehydration makes the blood thicker and heavier from lack of water, and therefore more likely to settle in the legs instead of circulating freely around the body. The thicker blood allows a blood clot to form and grow more quickly.

ii. VEIN CONSTRICTION. Dehydration dries the skin and constricts the surface veins. This slows down the blood circulation, also making your blood thicker, thus increasing the likelihood of a blood clot.

iii. HIGHER BLOOD PRESSURE. Dehydration puts your body under greater stress because all your organs start to compete for the limited amount of water circulating in the blood. This in turn increases your blood pressure. If a blood clot is formed, the high blood pressure can dislodge the clot and carry it through the body to a point where it blocks blood to the heart, the brain, the lungs, a limb, or some other part of the body.

iv. CHEMICAL CHANGES. Dehydration causes chemical changes in the body, which dramatically increase the levels of compounds associated with blood clotting.

So, to reduce the risk of DVT you have to reduce passenger dehydration. Airlines can best do this by encouraging passengers to drink more water and less alcohol, and by making cabin air less dry (i.e. by setting the cabin altimeter at, say, 5000 ft instead of the typical 8000 ft).

Russell Eaton
airtravelsurvival.com

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