Long-haul Flights and DVT

When your body heals from a superficial injury (e.g. at skin level), your body's natural response is to form a blood clot to limit excess blood loss, and will dissolve when no longer needed. Alternately your body may form a harmless varicose or spider vein. However, the deeper the vein a clot occurs in, the more likely it is to remain intact. This is dangerous because if it reaches your heart and blocks an artery, it could rupture and cause a heart attack or stroke. If it enters your lungs, it could prevent you from breathing. When you’re seating on a long flight, you’re more likely to develop one in your lower legs, and these clots are prone to dislodging and entering high-risk areas. It only takes a four-hour flight for your risk to increase.

There are many things you can do to reduce your risk of developing DVT during flights. Regular movement and stretching, adequate hydration, and as little alcohol or sleeping tablets as possible are all effective, as is a brisk walk after landing. To drastically reduce your risk of DVT further, you can wear graduated compression socks as they prevent blood 'pooling' in your calf muscles.

It’s important to always seek medical advice before taking a long flight. For example, if you’re over 60 and have high blood pressure, smoke regularly or are pregnant you could be at increased risk. In such cases, your doctor might prescribe you appropriate medication, which can also be used in combination with compression stockings/socks.