Deep Vein Thrombosis (DVT)

Today more and more people are on the move. But the huge increase in world travel, particularly long distance air travel, carries with it the potential health risk of a deep vein thrombosis commonly known as DVT. DVT was not previously recognised as a serious travel risk. However, it has now been proven to affect thousands of air travellers each year and can occur often in conjunction with an established illness or condition, where the natural tendency of the blood to clot is increased.

Long periods of immobility, particularly on long haul flights can cause circulatory problems. Enforced inactivity, sitting in cramped conditions for long periods of time, creates blood flow problems. An inefficient, sluggish blood flow increases the risk of a thrombosis. A thrombosis is a blood clot, which forms when the platelets of the blood stick together, and also stick to the sidewall of veins occurring most commonly in the veins of the calf. Other factors which increase this tendency, include being over 40 years of age, smoking, obesity, pregnancy, taking the contraceptive pill, or having recently undergone major surgery.

DVT is particularly serious when the blood clot gradually increases in size causing an eventual blockage in the vein. Occasionally bits of the clot will break free, and with a tail of debris behind it, can travel up the body to the right side of the heart, where it is pumped on into the lungs, causing serious breathing problems, or a pulmonary embolism. Many passengers suffer minor symptoms, such as fluid collecting in the lower limbs causing swollen legs and ankles, but others experience more serious symptoms including a rapid heartbeat, palpitations, and breathlessness or coughing. If a problem does occur, during or after a flight, it is essential to seek medical advice as quickly as possible, in order to avoid complications or possible death from cardiac or respiratory failure.

To prevent deep vein thrombosis, commonly known as “economy class syndrome” (because of the tight cramped seating arrangements in many planes), it is essential to walk up and down the aisles of the aircraft whenever possible during a long flight. One way to help avoid DVT is to do some simple leg and feet exercises throughout the duration of the flight. Others are to wear loose comfortable clothing during the flight and avoid crossing the legs, especially when sleeping. Long haul flights carry the most risk, but exercise and walking around whenever possible will improve circulation by encouraging action of the leg muscles. The calf muscles at the back of the lower leg pump and encourages the return of blood from the legs and feet back to the heart. On a long journey the air inside the plane’s cabin can become very dry, so it is advisable to drink plenty of fluids during the flight (and to avoid excess alcohol) in order to prevent the body becoming dehydrated. Dehydration can cause the blood to thicken.

One in 20 people, and I am included in this number, carry a gene factor known as Factor V Leiden. This gene mutation affects the blood’s clotting capabilities, and puts the carrier at a higher risk of flight related DVT. Most people are not aware that they are carriers or at greater risk, and my own vulnerability came a surprise to me. It was discovered after I had breast cancer, and was a result of medical testing to establish whether I carried the breast cancer gene. I have many young girls in my family who might have been at a higher risk of presenting with breast cancer had I their close relative, been found to carry the gene. Fortunately the tests concluded that I do not carry the breast cancer gene, but discovered that I do carry the Factor V Leiden gene. I was advised to take an aspirin prior to flying to lessen my risk of DVT.

Taking a simple aspirin before a long flight is a simple precaution, which can help thin the blood and discourage the blood from clotting. However aspirin is not advisable for anyone who has an established medical condition such as a stomach ulcer. If you are concerned about the risks involved with flying long distances, it is a good idea to talk to your GP, particularly if you have had phlebitis or a previous thrombosis.