Your Health A-Z

Prevent blood clots when you travel

There’s nothing quite as exciting as a holiday, especially if you’re going abroad, but with long-haul travel comes the risk of blood clots, particularly in the elderly. We chat to Dr Gavin Angel, a cardiologist at Mediclinic Morningside, about recognising and managing the risks.

Blood clots can be lifesaving in certain cases, especially when slowing or preventing excessive bleeding by plugging injured blood vessels. But when clots develop in your veins without dissolving naturally, they can result in anything from pain to a potentially fatal medical emergency.

Risk factors for blood clots

Dr Angel says the three main factors contributing to blood clots are categorised according to Virchow’s triad (formulated by German pathologist Rudolph Virchow).

‘Most people who get – or are predisposed to getting – blood clots either have one or a combination of the following factors,’ says Dr Angel:

  • Stasis of blood, where the blood doesn’t flow properly.
  • Blood is hypercoagulable, which means there’s an increased tendency to blood clotting.
  • An injury to the blood vessel or the lining of the blood vessel, or the blood vessel just isn’t working properly, known as endothelial disease or dysfunction.

‘The elderly are generally at higher risk of these three factors, so they’re more likely to have clot abnormalities or to get poor circulation and stasis of blood,’ explains Dr Angel. ‘They’re also more likely to have fragile vessels and problems in the walls of arteries’.

Yet it’s not only the elderly who are at risk of blood clots. Anyone who has any of the conditions mentioned in Virchow’s triad can be affected:

  • Pregnancy is also a hypercoagulable state, so the blood clots more easily. Generally there’s more stasis as well, because during pregnancy one’s circulation is not as good.
  • Family history: If anyone in your family has a clotting abnormality you could be predisposed – this can be checked for with blood tests.
  • Certain medications and drugs put people at higher risk.
  • Smoking.
  • Dehydration.
  • Injury and surgery: Especially orthopaedic injury or surgeries are considered high risk for developing clots.
  • Being admitted to hospital, as patients usually have at least one risk factor present.

Travel risks

Anyone who is at risk of clotting heightens the risk when travelling. However, Dr Angel stresses that this usually only applies to long-haul travel, not a two-hour flight from Johannesburg to Cape Town. ‘It’s not only because you’re sitting for a long time on international flights, it also has to do with the altitude – there’s less oxygen as well as unusual air pressure,’ he says. Long drives can also pose a risk because you’re stationary for an extended period.

The blood clots you get when flying would usually be in the leg or groin area, or upper limb, and is generally known as deep vein thrombosis (DVT), Dr Angel explains. He adds that the danger is that these clots can go up to the lungs, causing a pulmonary embolism (a blockage in the pulmonary artery – the blood vessel that carries blood from the heart to the lungs).

Preventing blood clots before and during travel

Fear not, even if you are at risk of clotting, you needn’t stay grounded for life. Whether you’re older or you fall into one of the high-risk groups, there are numerous ways to reduce the chance of blood clots before and during travel.

‘If you have a family or personal history of clotting abnormalities or of having a previous clot, before you travel you should see a physician who can prescribe medication,’ Dr Angel advises. ‘Before flying, you may benefit from taking blood-thinning tablets or having blood-thinning injections in the form of medications like Warfarin or one of the newer blood thinners like Xarelto.’

He suggests the following precautions to take during long-haul flights:

  • Move around regularly
  • Keep well hydrated
  • Avoid taking sleeping pills

In the interest of our patients, in accordance with SA law and our commitment to expertise, Mediclinic cannot subscribe to the practice of online diagnosis. Please consult a medical professional for specific medical advice. If you have any major concerns, please see your doctor for an assessment. If you have any cause for concern, your GP will be able to direct you to the appropriate specialists.