British Airways is currently being sued by three sufferers of Deep Vein Thrombosis after long haul flights. Discuss the medical evidence that maybe presented to the jury by lawyers representing both parties.

In fatal conditions pulmonary thromboembolization occurs this is the complication that results when a blood clot forms in a deep vein, breaks free and travels through the heart to an artery in the lung, where it blocks the blood flow.

If the clots are absorbed into the bloodstream they need to be treated by drugs that dissolve them, this prevents others forming. If the clot reaches the lung emergency medical assistance is required. The aircrews need to be taught the symptoms to look out for, which vary from swelling to cramping in the legs.

A passenger's daughter Sandra MacKay-Nicoll thinks her mother's death could have been prevented if she had known about the potential for blood clots on long flights. Joan MacKay died after 17 hours on a plane. Sandra thinks if her mum had known about the illness she would have got up and gone to the toilet and stretched.

Knowledge of this illness isn't widely spread. British Airways have exercises in one of their magazines but a lot of people don't read them. A video should be shown this would be more effective and make more people aware of the illness. Passengers should have to stand up now and again and do some exercises. On some American airlines they show aerobics videos so people can join in and stretch all their bodies mainly their legs.

Certain people are more vulnerable to deep vein thrombosis which include pregnant women, people who are overweight, smokers, people with coronary artery diseases and certain blood conditions, elderly people and if deep vein thrombosis has struck before.

But on the other hand air travel is not the only cause of deep vein thrombosis. 30,000 people a year die as a consequence of deep vein thrombosis. Only several hundred cases a year are due to air travel. These several hundred cases are out of over 600 million trips that planes have taken.

Air travel is not the only or even primary time the blood clots can develop it also can develop in individual seated theatres, cars, trucks, buses etc. The blood clots have been given the name "Economy-class syndrome" this is only when the blood clots appear on a passenger in a plane. But deep vein thrombosis has occurred in business class as well so this name isn't right.

A paper published in Chest (Feb99) states that out of 160 patients suffering from deep vein thrombosis only 9 patients travelled by air in the past 4 weeks, 28 by car and 2 by train. Doctor Patrick Kesteven of Newcastle University states although flying can be a risk there is no conclusive evidence that flying is a risk itself. It seems to be the immobility.

A rare case of deep vein thrombosis happened to a man called Paul Civill. He started off with a pain in his leg and after 8 hours he was pronounced dead. He hadn't flown or he hadn't done anything in his lifestyle that could have caused the illness. This proves that deep vein thrombosis could strike any time but mainly when you're immobilised

The clots can form anywhere in the body but they mainly occur in the legs and lower abdomen. People with their limbs set in plaster or from surgery when you're immobile.

Here is advice to avoid deep vein thrombosis when travelling by air, drink lots of fluids, no smoking, no alcohol, don't cross your legs when seated, stretch arms and legs, wear baggy clothes and remove shoes.

Flying can cause deep vein thrombosis but so can other methods of transport , but you are at risk if you fly in cramped conditions. Other reasons apart from travelling are mainly when people are immobile. "Economy class syndrome" has caused a great concern to the public recently. A lot more information is needed about the illness and this might decrease the number of deaths each year.

Deep vein thrombosis can be fatal or if treated not. A lot of cases aren't fatal or even caused by air travel. Are you going to get deep vein thrombosis next time you fly? Should British Airways get sued or not?

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