Dr. Akbar

Chief physician Steffen Lyduch, who specialises in aerospace medicine, outlines some basic advance precautions you can take if you are concerned about flying

If a passenger suffers from certain heart or lung diseases or from a low blood count, this may mean that not enough oxygen can be absorbed into the blood for distribution to the organs of the body. Signs of illness may then appear, depending on which organ is not being adequately supplied with oxygen.

If the heart is starved of oxygen, Angina Pectoris (heart cramp) may occur. If the brain is affected, this may cause
confusion, paralysis or loss of consciousness. If suffering from a fever, the body's need for oxygen is increased
significantly due to symptoms which may appear at a very early stage in the flight. Passengers with fever are
advised to avoid flying until the fever has subsided.

Passengers suffering from asthma must be in a stable state without recent attacks. Any medication should always be hand-carried.
For passengers with heart and lung diseases the rule of thumb is: "If you can walk the stairs to the first floor and
back with no great difficulty, then you can stand the reduced pressure in the cabin during flight."

According to the laws of physics, air expands when the atmospheric pressure is decreased. A balloon, which holds three liters of air at ground level, will thus expand to hold four liters in a pressurized cabin when the airplane has reached its cruising altitude.
You can feel this during takeoff when the air in the middle ear expands, and when it contracts during landing. The air from the middle ear can only enter and exit through the Eustachian Tube, the channel that connects the inner ear to the back of the naso-oral cavity. Because of the shape of the Eustachian Tube, it is easier for air to get out of the middle ear than to get in. It often needs a helping hand, by holding the nose and breathing out gently with the mouth closed (this is called the Valsalvas manoeuvre.
It is important to do this all the time the airplane is descending, since the negative pressure in the middle ear can increase to the point that it causes the Eustachian Tube to collapse. If the mucosa is thickened, as when you are suffering from a common cold, for example, pressure-equalization may be impeded or even be impossible, the
condition may become very painful and require treatment from a medical specialist. It is therefore advisable not to fly when the middle ear and sinuses are blocked due to an infection.
Some people, mainly children, have difficulties in carrying out the Valsalva manoeuvre. If you have problems, you could use "Otovent", a balloon with a special mouthpiece, which is placed on the nose and blown. This method is particularly effective and can be carried out by children from the age of three. Otovent is available from good chemists.
When having difficulties in equalising pressure in the middle ear or sinuses during the flight, nasal spray or drops
should to be taken as early as possible during the descent. Most Airliners carry a doctor's or attendant's kit, from which this medication can be issued on an emergency basis.
Air in the stomach and intestines expands in the same way, and when three litres of intestinal air become four litres in the pressurized cabin, it may be necessary, for the sake of one's own comfort, to discreetly get rid of this excess air. Since the air in the cabin is renewed approximately 25 times an hour (compared to once or twice an hour in an ordinary room) these gases will soon disappear, generally without disturbing the other passengers.

Deep Vein Thrombosis (DVT) has been called 'Economy Class Syndrome' by some media. This, of course, refers
to the possible connection between the risk of developing DVT and the relatively confined space available to the
passengers in economy class seats. DVT however, is not restricted to passengers in economy class; it also occurs
in passengers in Business Class and First Class. In fact, DVT can occur in any situation where a person is sitting
still for a long time, in the home, for example, or at work, on buses and also - naturally -in an airplane.
Under normal circumstances, blood is pushed back from the legs to the heart with the help of what is called the
"muscle pump" action, i.e., when we use the muscles in the legs, these veins contract and push the blood from the
legs back up to the heart. Valves in the veins make sure that the blood cannot run backwards.
DVT occurs particularly in situations when the blood is pumped back from the legs too slowly, or when it stops
completely. This may be due to sitting completely still without moving the legs. DVT can also occur if there are
defects in the valves in the veins, allowing the blood to flow backwards. If the blood is thicker than normal, because of dehydration (lack of fluid) for example, the risk of developing DVT increases. Pregnant women and women on birth control pills have an increased risk of developing DVT.
It is therefore of great importance that passengers constantly use the muscles in the legs by moving toes and
feet during the flight, and if possible go for small walks, preferably every hour.

The air temperature outside the plane is generally -54° C. This air is then taken into the plane and warmed up.
Since cold air does not contain much moisture, the humidity level in the cabin is very low, with most of the humidity coming from the passengers themselves (evaporation and exhaled air).
Cabin humidity is generally around three to five percent, compared with the normal 60% or so in temperate
latitudes. Since coffee, tea and, in particular, alcohol, have a dehydrating effect, the body may start to suffer from a lack of fluid. Passengers can help prevent dehydration by drinking plenty of water before and during the flight.

It is now possible to buy "medical" support hose / compression hose of a very high quality and which look like normal tights. They are available in several colours, including black for men. These support hose squeeze the
leg, mainly at the ankle and then decreasing up the calf, so that there is a graduated level of pressure is exerted
on the veins. The blood is thus pushed in the right direction, towards the heart. One example of these stockings is the support/compression hose marketed by Jobst/Beiersdorf, and which can be bought from most chemists. Passengers with an increased risk of developing DVT are advised to use such support stockings during flight.

Unless individuals have known allergies, a low dose of Acetylsalicylic acid (i.e., Junior Aspirin) is recommended
on the day of departure. This will reduce the propensity of the blood to cloth (same mechanism as when aspirin is
used for prevention of thrombosis.
If you are on regular medication, always bring this on board in your hand luggage. When travelling alone, you
should inform the cabin crew about this when boarding.

If in doubt about possible health risks if travelling by air, passengers are always advised to consult their General
Practitioner for assessment and advise.

Enjoy your flight!