Blood Clots on long-haul trips

A WHO study says the risk of developing deep vein thombosis doubles after 4 hours of travel including car and train journeys, estimating that one in 6,000 long-haul passengers is at risk.

Who are at risk? Tall people who legs are jammed in economy class and the very short whose feet do not touch the ground are particularly vulnerable to potentially dangerous blood clots linked to immbobility during travel. Also the obese, women on birth control pills and those with blood clothing disorders are also more susceptible, as are frequent travellers and those who take very long journeys.

The risk is immobility - without regular muscle contractions, blood starts to pool in the legs and can create conditions for a clot, or thrombus, to develop in deep veins. Thrombosis can be symptom-free to trigger cramps, soreness and swelling in affected areas. It is most dangerous in cases where blood clots travel through the body to the lung, blocking blood flow. Such pulmonary embolism, characterised by chest pain and breathing difficulties, can be fatal is untreated.

Once I was on a plane to San Francisco and the guy sitting at the window seat just slept and not move throughout the journey from Singapore to Seoul and onwards to San Francisco. I like the aisle seat because I can stretch my legs and move around without disturbing anybody.

To prevent, health experts advised travellers to exercise their calf muscles with up and down movements of the feet and ankle joints, and leave their seats for a few minutes when possible. They also caution air travellers against taking sleeping pills or drinking too much alcohol. People should also avoid wearing tight clothing that can constrain circulation.

Reference: The Straits Times, July 11 2007