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Monday, June 19, 2023

Clots on a Plane

Posted By: Advancing Care

Research has shown that longer flights of 6-12 hours may increase the risk of developing a clot

According to the Centers for Disease Control and Prevention (CDC), more than 300 million people travel on long-distance flights (generally more than four hours) each year. While there is still some uncertainty about the link between air travel and venous blood clots, research has shown that longer flights of 6-12 hours may increase the risk of developing a clot.

Here’s what you need to know before takeoff.

What can increase your risk of blood clots?

Whether traveling by plane, train or automobile, sitting still in a confined space for long periods of time can cause blood clots to form in the veins deep below the surface of the skin, particularly in the lower legs. When the clot forms in veins that are within the muscles of the leg, this is a deep venous thrombosis (DVT). The clot, or part of the clot, can detach itself from the walls of the deep vein and travel to the lungs where it eventually becomes lodged. This is a pulmonary embolism (PE).

More commonly the clot can form in a vein just below the skin, such as in a varicose vein, referred to as superficial thrombophlebitis (SVT). These superficial clots do not result in PE. DVT, PE and SVT represent a spectrum of a single disease, known as venous thromboembolism (VTE).

Joseph Fulton, MD

The risk of developing blood clots during air travel is influenced by a variety of conditions and health factors, according to Joseph Fulton, MD, a vascular surgeon at WMCHealth. “These risk factors include prior blood clots, recent surgeries (within the last three months), hypercoagulability or inherited risk factors, pregnancy, old age, smoking, diabetes, the use of contraceptives and the length of the flight,” explains Dr. Fulton.

What are the symptoms of a blood clot?

Roughly half of people with DVT experience symptoms, all of which tend to occur in the affected extremity. Keep an eye out for the following warning signs, especially during your next long flight or road trip:

  • Swelling in the calf, usually in one leg
  • Pain, tenderness or cramping in the affected area
  • A warm sensation

Symptoms of a PE include shortness of breath or difficulty breathing, irregular heartbeat, chest pain, lightheadedness and coughing up blood.

“Swelling of the feet, ankles or legs occurs in most people during long periods of travel. However, if you experience symptoms that signal a potential DVT or PE, you should head to the emergency room for prompt evaluation,” advises Dr. Fulton.

How can you prepare for your next long-distance flight?

If you’re starting to stress about your next trip, don’t worry—there are a few things you can do to stay safe and healthy. The first step is to invest in a pair of knee-high graded compression stockings that have a pressure of 15 mmHg to 30 mmHg. Not only do they provide comfort, compression socks can improve your circulation and decrease leg swelling.

“Staying hydrated is key, so make sure to drink plenty of water and limit your intake of alcohol and coffee, which can dehydrate you,” says Dr. Fulton.

To keep your legs moving and the blood flowing, try doing calf and foot exercises while sitting. Simple exercises such as knee and ankle raises and spelling the alphabet with your feet can prevent blood from pooling in your legs. If possible, choose an aisle seat so you can get up, stretch and walk around frequently during longer flights.

Still have questions? Our heart and vascular physicians offer a full range of preventive and treatment services to address all categories of adult heart and arterial disease. Make an appointment with WMCHealth’s Vascular Surgery and Laser Vein Center today.