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Air Travel and Blood Clots: What You Need to Know

on 15 April 2022

Blood clots, also called deep vein thrombosis (DVT), can be a serious risk for long-haul flight travelers.


What is considered a short-haul, medium-haul and long-haul flight?

A short-haul flight is one of up to 3 hours in duration. Medium-haul flights take 3-6 hours. A long-haul flight runs for 6-12 hours, whilst an ultra-long-haul flight is in the air for over 12 hours.

However, commercial flights are often categorized into long-, medium- or short-haul by commercial airlines based on flight length. Route category lengths tend to define short-haul routes as being shorter than 1,100–1,500 km, long-haul as being longer than 4,100–4,800 km, and medium-haul as being in-between.

Understand What Can Increase Your Risk for Blood Clots

Even if you travel a long distance, the risk of developing a blood clot is generally very small. Your level of risk depends on the duration of travel as well as whether you have any other risks for blood clots.
Your risk of developing a blood clot during air travel is increased by the following:
• A previous blood clot
• Family history of blood clots
• Recent surgery, hospitalization, or injury
• Use of estrogen-containing birth control or hormone replacement therapy
• Current or recent pregnancy
• Older age (risk increases with age)
• Obesity
• Limited movement

Recognize the Symptoms

Deep Vein Thrombosis (DVT)
About half of people with DVT have no symptoms at all. The following are the most common symptoms of DVT that occur in the affected part of the body (usually the leg or arm):
1. Swelling of your leg or arm
2. Pain or tenderness that you can’t explain
3. Skin that is warm to the touch
4. Redness of the skin
If you have any of these symptoms, contact your doctor as soon as possible.
Pulmonary Embolism (PE)
You can have a PE without any symptoms of a DVT. Symptoms of a PE can include:
1. Difficulty breathing
2. Faster than normal or irregular heartbeat
3. Chest pain or discomfort, which usually worsens with a deep breath or coughing
4. Anxiety
5. Coughing up blood
6. Lightheadedness, or fainting
If you have any of these symptoms, seek medical help immediately.

Reduce Your Risk of Blood Clots During Travel

• Know what to look for. Be alert to the signs and symptoms of blood clots.
• Talk with your doctor if you think you may be at risk for blood clots. If you have had a previous blood clot, or if a family member has a history of blood clots or an inherited clotting disorder, talk with your doctor to learn more about your individual risks.
• Move your legs frequently when on long trips and exercise your calf muscles to improve the flow of blood. If you’ve been sitting for a long time, take a break to stretch your legs. Extend your legs straight out and flex your ankles (pulling your toes toward you). Some airlines suggest pulling each knee up toward the chest and holding it there with your hands on your lower leg for 15 seconds, and repeat up to 10 times. These types of activities help to improve the flow of blood in your legs.
• If you are at risk, talk with your doctor to learn more about how to prevent blood clots. For example, some people may benefit by wearing graduated compression stockings.
• If you are on blood thinners, also known as anticoagulants, be sure to follow your doctor’s recommendations on medication use.

Source: CdC.gov  and en.wikipedia.org

Last Updated: 15 April 2022
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