The risk of developing VTE approximately doubles after travelling by air for more than 4 hours, however, lack of mobility rather than cabin pressure is likely to be the main cause. Therefore, the risk of VTE applies to any type of journey where mobility is restricted for long periods.
This condition is caused by reduced blood flow which can lead to blood clots developing in a vein, normally in the lower part of the body. Blood clots that develop within deep veins, commonly in the legs, are known as deep vein thrombosis (DVT). Complications can arise if parts of the clot break away and travel through the bloodstream to the lungs where they may block an artery, causing a pulmonary embolism (PE).
If you are over 40, you are considered to be at risk and there are other known risk factors including:
- History of DVT
- Cancer – including cancer treatment
- Serious medical illness such as heart, lung or inflammatory bowel disease
- Combined contraceptive pill or hormone replacement therapy (HRT)
- Recent serious injury or trauma
- Long periods of immobility due to illness or recent surgery
- Varicose veins
- Pregnancy or less than 6 weeks after birth
We recommend travellers with any of these conditions seek advice from their GP for an assessment before taking long journeys.
Compression stockings can significantly reduce the risk of DVT and leg swelling (oedema) whilst travelling. Compression stockings or flight socks (Level 14-17mmHg – Class 1) are recommended to help improve blood flow, however, it is crucial that they fit correctly to ensure they do not further increase the risk of DVT. A pharmacist or health professional should be able to give advice on fitting.
Here are some tips for reducing the risk of DVT and leg swelling whilst travelling:
- Wear loose, comfortable clothes
- Remain hydrated
- Avoid excess alcohol
- Walk around as often as possible
- Exercise your calf and foot muscles regularly
- Avoid having bags in front of your feet
- Recline your seat when possible
- Do not take sleeping tablets
These exercises will help increase the blood flow in your legs:
- Bend and straighten legs, feet and toes
- Press the balls of your feet hard against the floor
- Stretch your legs as often as possible
Following the journey, make sure you have the opportunity for a short walk straight away. Slight puffiness of the feet and ankles is common after a long journey, however, if you develop swelling or pain in the legs or experience any breathing difficulties, seek urgent medical advice.