A pulmonary embolism is a blockage in one or more of the blood vessels that supply blood to the lungs. Most often these blockages are caused by blood clots that form somewhere else (mainly from legs and pelvic vessels) and then travel to the lungs. In rare cases, blockages can also be caused by air bubbles, tiny globs of fat, or pieces of tumor that travel to the lungs. These clots clog the blood vessels, reduce the blood flow to the lungs and impair the gas exchange. This can cause symptoms such as chest pain, difficulty breathing, or coughing up blood. In severe cases, it may result in collapse and sudden death.

Long airplane flights or multiple flights in a short period can be associated with pulmonary embolism. Any situation in which the leg is bent at the knee for prolonged periods without much active motion may lead to a reduction of blood flow and increase the risk of blood clots. Other factors can increase this risk, such as recent surgery, taking oral contraceptives or hormone therapy, pregnancy, cancer, heart problems, and older age. Inherited genetic factors may also play a role. Patients with severe COVID 19 are also at increased risk of developing blood clots.

D-dimer blood test is used to diagnose the problem, which often goes up in people with embolism. CT pulmonary angiography is the confirmatory test. It is a special kind of chest scan used to find out the number of blood vessels blocked and the amount of clot burden. Blood clots in the lungs are treated with medicines that keep clots from getting bigger. These medicines are called "anticoagulants" or "blood thinners," although they do not actually thin the blood. You will need to take the medicine for at least 3 months (and sometimes longer). It's also important because people who have a clot are at risk of developing another clot, especially in the first few months.

Here are some things you can do to help prevent a clot during a long flight hauls: Getting up frequently and walking in the aisle of the plane increases blood flow and may reduce the risk of clots forming, but is not always practical or safe. The simplest preventive measure is to frequently “pump your feet” while sitting in your seat. Alternately lifting the toes and then lifting the heels increases blood flow in the calf veins and reduces the risk of forming blood clots. Properly fitted graduated compression stockings have been shown to be of some value.

Dr. Rakesh Kodati


Consultant Pulmonologist, Star Hospitals

For Appointments, Call: 040 4477 7700