Tips for Trips

I’ve not written any new items for a couple of days while I was in England and out of range of anything resembling a decent Internet connection.

But a grand total of seventeen hours on planes made me think that it’s high time to tell you about some of my tips and techniques for dealing with the rigors of flying.

I’ve got so many of them that my tips will stretch over more than one article.

By now most people will have heard about the importance of:

1. Maintaining hydration: the low pressure and dry atmosphere on planes can quickly dehydrate us. I try to drink at least 20 fluid ounces every two hours that I’m in the air.
2. Avoid drinking alcohol and coffee.
3. Keep mobile. When it is safe to do so: walk up and down the aisle. Stretch your legs and arms and gently rotate your neck while sitting in you seat.

The most worrying things about flying is the risk of developing a Deep Vein Thrombosis (DVT).  This is an important topic: one in 2,000 long-distance passengers will suffer a blood clot, which can be fatal if the clot detaches and reaches the lungs: this is known as pulmonary embolism. DVTs are more likely to occur if there is a change in the rate of blood flow, the character of the blood of the normal functioning of the walls of the large veins. There are a number of well-recognized risk factors for the development of DVTs:

1. Obesity
2. Immobility
3. Oral contraceptives
4. Some cancers
5. Cigarette smoking

There is a great long list of potential causes, but our focus today is on factors that can increase your risk of developing a DVT if you fly.

DVTs have been recognized to occur not just in passengers on planes, but also in people at extremely high altitude.

For many years it has been assumed that the low pressure and the immobility together increase the risk of DVT. But new research from the Universities of Leicester and Aberdeen was published in the Journal of the American Medical Association in May.

In a study of 73 people, the researchers found that sitting for long periods was the main cause, and warned people about all forms of travel.

During the study, the volunteers spent eight hours sitting in chambers with reduced air pressure and oxygen. They were allowed to move around for a couple of minutes each hour. They were then also tested in a chamber without changes in the atmosphere. The idea was to simulate the conditions on a plane. Blood samples were taken before and after each "flight" to check for factors involved in blood clotting.

For all these factors, no significant differences were seen between blood samples taken from volunteers on a simulated flight or exposed to normal air pressure. So it is not the low air pressure and oxygen saturation that is to blame: it is the lack of movement.

It is also unlikely that the advice to take an aspirin before a flight is going to be much help.

During my travels I have seen people selling extracts of horse chestnut (Aesculus hippocastanum) to prevent DVTs. There is actually some research that horse chestnut can help with chronic venous insufficiency. But there is no credible evidence that taking a couple of horse chestnut capsules will prevent a DVT, or the less severe problem of ankle swelling. And horse chestnut is well known to have a number of side effects, so there doesn’t seem to be much point in taking it to prevent ankle swelling and DVTs when flying.

The smart move (ha!) is to do regular exercise during flight, and to avoid dehydration.

I’ll tell you some of my tips for turning flights into highly productive work time and how to avoid jet lag in other posts.