IAMAT |International Association of Medical Assistance to Travellers| IAMAT |International Association of Medical Assistance to Travellers|

Travel Health Journal

prevent DVT on airplanes

How to prevent DVT during air travel

With some airlines planning to reduce seat size even further, the topic of cramped cabin space and deep vein thrombosis (DVT) has been popping up a lot recently. Studies haven’t shown a connection between seat size and DVT risk, but awareness of DVT is important for anyone planning a long-haul trip.

Deep Vein Thrombosis and Pulmonary Embolism

DVT is a condition where blood clots develop in the deep veins, usually in the legs. These clots can cause localized pain, redness, swelling, and be warm to the touch, but you may not have any symptoms. DVT becomes dangerous when a piece of clot breaks off and travels to the lungs, causing a Pulmonary Embolism (PE) which can be life-threatening. Pulmonary Embolism symptoms include sudden shortness of breath, rapid heart rate, chest pain, and light-headedness or fainting. This is different than a stroke or heart attack which occur when blood clots block the arteries. When you suffer from both DVT and a Pulmonary Embolism it’s known as Venous Thromboembolism (VTE).

Understanding the risk

Air travel is what many people associate with DVT, but any period of prolonged sitting (over 4 hours) can increase the risk of blood clots. This includes travelling by car, train, or bus or even sitting at a desk for long periods of time.

Many different factors contribute to increased risk of DVT, but being immobile for a long period of time (especially if it cuts off circulation to your legs) is probably the most important. Other risk factors include obesity, smoking, height (being very tall or very short), pregnancy, taking hormones such as birth control pills or hormone replacement therapy, being over 40 years of age, varicose veins, previous incidence of DVT or Pulmonary Embolism, cancer, recent surgery,  and a genetic predisposition to blood-clotting problems.

You can reduce the risk

You can reduce the risk of DVT by limiting the amount of time you spend sitting. Here’s what you can do:

  • When booking your flight, choose an aisle seat so you have the freedom to stand up, stretch your legs, and walk around. If you can’t get an aisle seat, don’t be shy about asking your seatmate to get up.
  • Wear comfortable, loose fitting clothing.
  • Don’t stow any luggage underneath the seats in front of you so that you can move your legs.
  • Avoid dehydration: Drink water and don’t consume alcohol.
  • Walk around the cabin for a few minutes every hour to get the blood moving in your legs. If you have time before your flight, take a walk around the terminal.
  • Calf muscle exercises like foot pumps are also helpful. While sitting, point your toes down to the floor and raise your heels, then do the opposite and point your toes toward the ceiling with your heels on the floor. Repeat several times. (A diagram of this exercise is available here in Figure 1, exercise 1 and 2.)
  • If you are at higher risk of getting DVT, talk to your doctor before your trip. You may want to get graduated compression stockings or may be prescribed an anticoagulant if you have a history of DVT. Note that taking Aspirin does not prevent DVT.
  • If you suspect DVT or PE, seek medical assistance immediately. It’s an emergency.

Our Guide to Healthy Travel has a checklist of what to do to prevent DVT. Members can download the Guide through our eLibrary.

Photo by Pexels.


Further reading

Pulmonary Embolism and Deep Vein Thrombosis, by Samuel Z. Goldhaber, MD; Ruth B. Morrison, RN, BSN, CVN.

WHO Research Into Global Hazards of Travel (WRIGHT) Project

Preliminary Evaluation of Recommended Airline Exercises for Optimal Calf Muscle Pump Activity, by K.J. O’Donovan, T. Bajd, P.A. Grace, D.T. O’Keeffe, G.M. Lyons.

Immobility, circulatory problems and deep vein thrombosis (DVT)