Blood clots can form in the deep veins (veins below the surface that are not visible through the skin) of your legs while you are travelling because you are sitting still in a confined space for long periods of time. The longer you are immobile, the greater your risk of developing a blood clot.
Sometimes the blood clot will dissolve on its own. However, a serious health problem can occur when a part of the blood clot breaks off and travels to the lungs causing a blockage. This is called a pulmonary embolism, and it may be fatal. Pulmonary embolism following air flight was first described in 1954 and was termed “economy class syndrome” in 1977. This term is not used today because we know that venous thromboembolism is not restricted to economy class passengers. In fact, it’s not only limited to long duration travel in an aircraft but any confinement in small spaces such as a car, bus or train travel.
With many of us heading across the country, or across the planet, for our winter holiday, it is important to understand who is at risk for getting a thrombosis (clot), ways to prevent getting one, and how to recognise if you’ve developed one.
Risk factors for thrombosis in travellers:
- Past or family history of DVT (deep vein thrombosis)
- Poor veins in legs such as varicose veins or injured veins
- Coagulation (clotting) disorders
- Recent trauma or surgery, especially leg, hip or pelvis
- Medical predisposition such as obesity, smoking, older age, chronic disease, malignancy
- Pregnancy and the two months after giving birth, hormone replacement therapy (HRT) or oral contraceptive pill
- Cabin-related factors such as cramped position, immobilisation and dehydration
- Prolonged journeys
“Pulmonary embolism is not only limited to long duration travel in an aircraft but any confinement in small spaces such as car, bus or train travel.”
How do we reduce our risk of getting blood clots?
- Plan day or night stopovers to break trips up into shorter segments.
- Stand up and move around frequently.
- Request a bulkhead or aisle seat.
- Perform leg and calf stretching exercises every one to two hours.
- Maintain adequate fluid intake (at least 2 litres per 24 hours).
- Restrict alcohol and caffeine intake.
- Travellers who are at slightly higher risk should consider purchasing below-knee class I graduated compression stockings.
- High-risk patients should speak to their doctor about an injection of a blood-thinning medication before flying.
- It is important to note that aspirin has absolutely no evidence for preventing clotting in the venous system and will not prevent a DVT.
Symptoms of a DVT include:
- DVT usually (although not always) affects one leg
- Swelling in one (or both) legs
- Pain or tenderness in one or both legs, even if it’s just when you stand or walk
- A heavy ache in the affected area
- Warm skin on your leg
- Red or discoloured skin on your leg
If a DVT breaks loose and travels to the lungs, it causes a pulmonary embolus and can be deadly. Look out for the following (particularly following recent travel):
- Sudden coughing, which may bring up blood
- Sharp chest pain
- Rapid breathing or shortness of breath
- Severe light-headedness
You might have simply picked up an infection on your holiday, but rather be safe than sorry and call your doctor immediately.
Happy, safe and healthy holidays everyone!