Date: July 16, 2019

Mainly cloudy with 60 percent chance of showers. Risk of a thunderstorm this afternoon. Wind southwest 20 km/h gusting to 40. High 29. Humidex 37. UV index 7 or high.


Feels like 36C

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Thrombosis Prevention For Travellers

This page was reviewed or revised on Thursday, July 21, 2016 3:58 PM

Environmental Health and Prevention Services

What is Thrombosis?

Thrombosis (Throm-bo-sis) is the formation of a blood clot inside a blood vessel. These clots form most often in the lower half of the body such as leg veins. These are known as deep vein thromboses (DVT).

If a clot breaks off and finds its way to one of the lungs it can lead to a pulmonary embolism (pul-mun-air-ee-em-bo-liz-em). The clot can also lodge in the brain, heart or other area and cause damage to that organ.

DVT is more common in adults over age 60 but can occur in ay age group.

Are long flights dangerous?

Long flights that last several hours raise the risk of clots forming. The following factors cause fluid to collect in the legs adding to the risk of a clot.

  • Limited motion and sitting for a long time in cramped areas cause veins in the knee and the groin to bend in two and slows the flow of blood.
  • Drop in cabin pressure causes vein walls to stretch and slow the blood.
  • Lower humidity causes a loss of fluid in the body. That thickens the blood and makes clots easier to form.

Risks for Thrombosis

  • Varicose veins
  • Phlebitis (fluh-bi-tis)
  • Cardiac problems
  • Age (seniors)
  • Pregnancy
  • Recent surgery
  • Smoking
  • Overweight
  • Oral birth control
  • Alcohol (expands the blood vessels, slows blood flow)

Ways to prevent Thrombosis

  • Walking is the most important factor. If you can, stand up often and take a walk up and down the aisles to get your blood circulating. If not possible, leg exercises can be done at your seat.
  • Avoid having the seat press against the back of your legs (occasionally rest your feet on your carry-on luggage).
  • Clothing should be loose and comfortable.
  • Drink lots of water, fruit or vegetable juices. Since the humidity is lower, the body needs more liquids.