Oxygen therapy
Hyperbaric Oxygen Therapy is a treatment which essentially
involves providing the body with extra oxygen. The word 'Hyper' means
'increased' and 'Baric' refers to pressure. As we all know, Oxygen is one of
the gases in the air that we breathe and is essential for life. The air that
we breathe normally contains 21% oxygen.
Breathing in 100% oxygen under
increased pressure within a hyperbaric chamber allows extra oxygen to be
forced into the blood stream and dissolved at a much faster rate than if
pressure was not used. Another effect is the increased oxygen transport
capacity of the blood. Under atmospheric pressure, oxygen transport is
limited by the oxygen binding capacity of hemoglobin in red blood cells,
which almost reaches saturation at atmospheric pressure, very little oxygen
being transported by plasma. However Oxygen transport by plasma is
significantly increased under HBO therapy. This extra oxygen can help where
healing is retarded due to infection or limited blood supply through tissue
damage.
The treatment is normally pain free and is carried
out in specially-designed chambers known as "hyperbaric chambers".
There are
two basic types of chamber: monoplace chambers and multiplace chambers.
A monoplace hyperbaric chamber is for treating one
person at a time and involves the patient lying on a padded stretcher that
is then slid into a clear plastic chamber about 2ft in width. Once inside,
the door is closed and the chamber is pressurized.
Multiplace hyperbaric chambers can treat several
people at a time. The multiplace chamber is the type most frequently used.
These chambers are big enough to accommodate sometimes as many as a dozen
patients at a time and it is possible to walk into them. Patients either sit
on benches or lie inside these chambers. 100% pure oxygen is administered
via either a mask or a clear plastic hood. HBO sessions usually last from
one to three hours depending on the nature of the treatment program.
Treatment sessions within the hyperbaric chamber are normally repeated over
several days or even weeks.
HBO therapy is increasingly being used for helping
patients who have been subjected to conventional radiotherapy
and are now suffering the after-effects. A major problem with radiotherapy is that, since it not only kills cancer
cells but also nearby cells at the same time, it can cause changes in
the oxygen supply to tissues in the treated area, since less blood is
supplied to the area. The result is that it becomes more difficult for oxygen
and essential nutrients to reach the tissues. Over a period of time these
tissues can become very fragile, break down and ulcerate. Sometimes tissue
can even completely die (radiation necrosis).
