What is it: decompression sickness, also called the
bends, is related to great changes in environmental
pressure. It is caused by nitrogen bubbles forming
in the bloodstream and tissues of the body. The bubbles
occur if you move from deep water towards the surface
(where the surrounding pressure is lower) too quickly
. It is most usually associated with divers, but can
also occur in fliers in a non pressurised cabin when
there is a major change in altitude. In the most serious
cases decompression sickness can lead to unconsciousness
or death.

What are the symptoms: the symptoms generally
appear in a relatively short period after completing the
dive. Almost 50 per cent of divers develop symptoms
within the first hour after the dive, 90 per cent within
six hours and 98 per cent within the first 24 hours.
In practice this means symptoms that appear more than 24
hours after the dive are probably not decompression
sickness. An exception is if the diver has travelled
in an aircraft or has been travelling in the mountains.
Under these circumstances, low pressure can still trigger
decompression sickness more than 24 hours after the last
dive. As a result, it is wise not to fly within 24 hours
of a deep dive. Mild forms of decompression sickness
can resolve themselves without treatment or by breathing
100 per cent oxygen at the site of the accident. The
symptoms of decompression sickness vary because the
nitrogen bubbles can form in different parts of the
body. These can include pain in the joints
“bends”. a headache or vertigo, unusual
tiredness or fatigue, confusion, a rash, shortness of
breath, tingling in the arms or legs, muscular weakness or
paralysis, a burning chest pain with a deep breath, a
cough or ear or sinus pain.

What happens if I get it: if you suspect
decompression sickness, stop the dive, initiate first aid,
and summon assistance from a specialist in divers'
medicine. Treatment is oxygen on site and during
transportation, followed by treatment in a decompression
chamber.

How can I avoid decompression sickness?

· Dive within the limits set out in the diving
tables.

· Keep your rate of ascent to a maximum 10m/min.

· Don't plan any dives that need a
decompression stop in the water.

· Make a three-minute safety stop at a depth of 5m.

· Don't dive more than three times in one day.

· If you plan more than one dive in one day, start
by making the deepest dive first.

· If you are diving for several days in a row, have
a dive-free day after two to three days.

· Don't do any hard work before or after
diving.

· Drink lots of liquid before diving. Lack of fluid
due to heat or excess alcohol is dangerous.

· Make sure you are in good physical condition and
well rested. Have regular medical checkups.

· Make sure there is an interval of at least 24
hours between diving and travel by air or climbing up
mountains. If you have had decompression treatment, the
recommended interval before the next dive is at least 48
hours.