Deep Vein Thrombosis [DVT]
 

An Israeli scientist says Jesus died from deep vein thrombosis.  I don't know how valid that thesis is, but I do know that there is some evidence that long-haul flights are in some way related to DVT.  This may be especially true for passengers who have little or no in-flight exercise and are seated in Economy, where the seats are cramped and uncomfortable.

The experts are not completely certain as to all the casual factors involved in DVT.  However, they are agreed that lack of exercise, or immobility, during long-haul flights are major underlying risks.  They have also concluded that people at increased risk of DVT/PE are, in general, more likely to develop travel-related DVT/PE.

Although the incidence of DVT relating to air travel is admittedly small, Economy class passengers should carry out some sort of in-seat exercises and, whenever safe, should walk the isles. 

What is DVT:

Deep vein thrombosis [thrombosis means forming a blood clot] is a blood clot [a jelly-like mass of congealed blood] within a vein deep in the body.  Usually, the body absorbs the clot once bleeding stops and healing begins. 

DVT occurs when a large blood clot, which formed in a deep vein, remains there.  It becomes dangerous when the clot is dislodged and travels all the way to the lungs where it blocks a vessel.  This condition is known as Pulmonary Embolism [PE].

DVT Symptoms:

Symptoms include swelling, pain, tenderness and redness most often at the back of the leg, below the knee.  It is frequently, but not always, confined to only one leg.  DVT can also cause breathlessness, chest pain and, in severe cases, collapse.  However, often times there are no symptoms at all, and the condition only become obvious when a Pulmonary Embolus [PE] develops from the clots in the legs.

Bending the foot upward, towards the knee, may make the pain worse.

The association of DVT with air travel is a rare condition.  However, DVT follows varicose veins as the second most common vascular problem in the United States, affecting as many as 600,000 individuals every year.  No matter the cause, it is a very serious condition requiring urgent medical treatment.

Who's at Risk of DVT/PE:

The risk of Deep Vein Thrombosis and Pulmonary Embolus is not high; at greatest risk are those:

• Who are smokers;
• Those who are diabetic;
• With varicose veins;
• Who are obese;
• Suffering from dehydration;
• Women who:
  • Are pregnant;
  • Have recently had a baby;
  • Are taking the contraceptive pill; or
  • Are on hormone replacement therapy or HRT;
     
• Over 40 years of age;
• Who have already had blood clots;
• With a family history of blood clots;
• Suffering from, or who have had treatment for, cancer;
• With certain blood diseases;
• Being treated for heart failure or circulation problems;
• Who have had recent surgery, especially on the abdomen, hips or knees;
• Those who have just suffered a bone fracture; or
• Who have an inherited clotting tendency.

Causes:

The causes of DVT, and PE, are not well understood.  What is known is that those at risk, as enumerated above, constitute about 90 to 95% of those who fall victim to DVT and/or PE.

What is well understood is that Deep Vein Thrombosis can occur in normal veins for no obvious reason.  It is also well understood that it is linked with people who have been immobile for long periods of time.

Recommendations:

If any of the above listed risk categories apply to you, or if you have any other concerns about your health and flying, we recommend that you seek medical advise before traveling.  We also recommend that you do the following to avoid DVT/PE and to enhance your in-flight comfort:

• Wear compression stockings to prevent feet and ankle swelling.  This may also improve the return of your blood from the lower legs to the heart.  Such stockings, which should be fitted to your individual measurements, can be purchased from medical and surgical supply companies.
• Move your legs and feet for three to four minutes per hour while seated;
• Move about the cabin whenever safe;
• Do the exercises listed in our article 'In-flight Exercises'.

© Copyright 1999 - 2008 by Sharon Atchley.  All rights reserved.  Updated:  10/16/2008