When traveling over long periods of time, especially in the air, the contraction of muscles is an important factor in helping to keep blood flowing through the veins, especially in the legs. Continued immobility can occur especially when seated on an aircraft which can lead to pooling of blood in the legs which can cause swelling, stiffness and discomfort.
Deep Vein Thrombosis occurs more commonly in older people who travel, with the following information providing solo travelers over the age of 50, a better understanding of DVT and a range of advice including exercises for those planning to undertake long duration travel.
Note: The following material has been provided for general informational purposes only. It is not intended to be relied on as a substitute for professional medical advice. No person should act, fail to act, disregard professional medical advice, or delay seeking professional medical advice on the basis of this material. The Travelnanna website, nor its representatives does not guarantee the accuracy, currency or completeness of any of this information and will not be liable for any loss, damage or injury directly or indirectly caused by this material or its use.
Immobility, Circulatory Problems And Deep Vein Thrombosis (DVT)
It's been established that immobility is one of the factors that can lead to the development of a blood clot in a deep vein, known as 'Deep Vein Thrombosis', (DVT). DVT can occur as a result of prolonged immobility during the course of long distance travel by car, bus, train or air.
DVT Image of Red Blood Cells Magnification X5000
The World Health Organization undertook a major research study called 'WHO Research Into Global Hazards of Travel' (WRIGHT) in order to establish if the risk of venous thromboembolism is increased by air travel in order to determine the magnitude of the risk and the effect of other factors on the risk, in addition to the study of the effectiveness of a range of preventive measures.
The findings of the studies indicate the risk of venous thromboembolism is increased 2 to 3 fold after long haul flights of more than four hours in duration together with other forms of travel involving prolonged seated immobility. The risk increases with the duration of travel, and with multiple flights within a short duration. On average 1 passenger in 6,000 will suffer from venous thromboembolism after undertaking a long haul flight.
In most cases of Deep Vein Thrombosis, the clots formed are small and do not cause any symptoms. Generally the body is able to break down the clots and there are no long term side effects for travelers.
Larger clots however, may cause symptoms such as swelling of the leg, tenderness, soreness and pain. Occasionally a piece of a clot may break off and travel with the bloodstream,which may become lodged in the lungs. This is known as pulmonary embolism and may cause chest pain, shortness of breath and in severe cases, sudden death. This can occur many hours or even days after the formation of the clot in the leg.
Signs And Symptoms
Symptoms of DVT can include swelling, tenderness and sometimes warmth to the affected limb. However up to 50% of patients with a DVT show no symptoms. These are called ‘silent’ or ‘asymptomatic’ DVTs. Silent DVT's may resolve by themselves or can lead to other complications.
Other conditions may present with similar symptoms to a DVT. These include soft tissue injury (muscle strain), inflammation of superficial veins (phlebitis), infection (cellulitis), skin inflammation (dermatitis) or a ruptured cyst behind the knee (ruptured Baker’s cyst).
Medical research indicates a number of factors that may present an increased risk of blood clots in the legs including:
- Personal or family history of DVT.
- Recent surgery or injury, especially to lower limbs or abdomen.
- Blood disorders leading to increased clotting tendency.
- Immobilization for a day or more.
- If you are aged above 40 years.
- Oestrogen hormone therapy, including oral contraceptives.
- Tobacco smoking.
- Former or current malignant disease.
- Heart failure.
- Varicose veins.
It is advisable for people with one or more of these risk factors to seek specific medical advice from their doctor or a travel medicine clinic prior to embarking on a flight of 4 or more hours in duration.
Blood Circulation and Muscle Relaxation
When a passenger is sitting upright and inactive for a long period of time, several things can happen:
The central blood vessels in the legs can be compressed, making it harder for the blood to reach the heart.
Muscles can become tense, resulting in backaches and a feeling of excessive fatigue during or even after a flight.
The normal body mechanism for returning fluid to the heart can be inhibited and gravity can cause the fluid to collect in the feet, resulting in swollen feet after a long flight.
Some studies have concluded that prolonged immobility may be a risk factor in the formation of blood clots in the legs potentially resulting in deep vein thrombosis (DVT). Particular medications and medical conditions may increase the risk of formation of blood clots if associated with prolonged immobility.
There are a number of exercises recommended by airlines which are designed to provide a safe way to stretch and enable movement in certain muscle groups which can become stiff, as a result of long periods of sitting.
These exercises may be effective at increasing the body's blood circulation and massaging the muscles. The following range of exercises are recommended by Qantas Airlines Australia for passengers, with many other airlines offering similar advice for travelers.
The airline recommends these exercises be undertaken around for three or four minutes every hour, with occasional walking around the aisles of the aircraft. None of the following exercises should be performed if they cause pain or cannot be done with ease.
1. Ankle Circles
Lift feet off the floor. Draw a circle with the toes, simultaneously moving one foot clockwise and the other foot counterclockwise. Reverse circles. Rotate in each direction for 15 seconds. Repeat if desired.
2. Foot Pumps
Foot motion is in three stages.
- Start with both heels on the floor and point feet upward as high as you can.
- Put both feet flat on the floor.
- Lift heels high, keeping balls of feet on the floor. Repeat these three stages in a continuous motion and in 30 second intervals.
3. Knee Lifts
Lift leg with knee bent while contracting your thigh muscle. Alternate legs. Repeat 20 to 30 times for each leg.
4. Neck Roll
With shoulders relaxed, drop ear to shoulder and gently roll neck forward and back, holding each position about five seconds. Repeat five times.
5. Knee to Chest
Bend forward slightly. Clasp hands around the left knee and hug it to your chest. Hold stretch for 15 seconds. Keeping hands around the knee, slowly let it down. Alternate legs. Repeat 10 times.
6. Forward Flex
With both feet on the floor and stomach held in, slowly bend forward and walk your hands down the front of your legs toward your ankles. Hold stretch for 15 seconds and slowly sit back up.
7. Shoulder Roll
Hunch shoulders forward, then upward, then backward, and downward, using a gentle circular motion.
The benefits of most recommended precautionary measures in travelers at particular risk for Deep Vein Thrombosis are unproven and some might even result in harm. Additional and further study to identify effective preventive measures are ongoing. However there are a number of recommendations including general advice for passengers including;
Moving around the cabin during long flights helps to reduce any period of prolonged immobility, although this may not always be possible. Furthermore any potential health benefits must be balanced against the risk of injury if the aircraft were to experience sudden turbulence. A regular trip to the bathroom, e.g. every 2–3 h, is considered to be a reasonable measure.
Many airlines provide helpful advice on exercises that can be carried out in the seat during flight. Exercise of the calf muscles can stimulate the circulation, alleviate discomfort, fatigue and stiffness, and may reduce the risk of developing DVT.
Hand luggage should not be placed where it restricts movement of the legs and feet, and clothing should be loose and comfortable.
In view of the clear risk of significant side effects and absence of clear evidence of benefit, passengers are advised not to use aspirin specifically for the prevention of travel related DVT.
Travelers at greatest risk of developing DVT may be prescribed specific treatments and should consult their doctor for further advice.
Anticoagulation is often called thinning the blood. Medicines which work in this way are called anticoagulants. However they do not actually thin the blood they alter certain chemicals in the blood to stop clots forming so easily. Anticoagulants do not dissolve the clot. Anticoagulation prevents a DVT from getting larger and prevents any new clots from forming. The body's own healing mechanisms can then get to work to break up the clot.
If you have a DVT, you will usually need an anticoagulant medicine for at least three months however tablets may take a few days to start working properly, so normally a patient is given fast-acting injections for the first few days until the tablets are working properly. A serious embolus is rare if anticoagulation treatment has began during the early stages of contracting a DVT.
Injections used are usually given just under the skin (subcutaneously). The ones generally used are:
One of a number of heparin injections - dalteparin, enoxaparin or tinzaparin.
Once a DVT has been confirmed the patient will also be started on an anticoagulant tablet. The length of time a patient will be advised to take anticoagulation depends on various factors. Anticoagulation may be only required for a few months, however some people continue to have an increased risk of having a DVT. In this case, the anticoagulation treatment may be long term.
As a guide, for a DVT that happens below the knee, around three months of anticoagulant treatment is required. Some people at higher risk of another DVT may need longer than this. The length of time of anticoagulation varies from person to person. Your doctor or anticoagulant clinic will advise you how long your treatment will be for.