Comeback in Medicine
These slimy and wriggly creatures that are guaranteed to turn the
stomach of the most hardened doctor and the most stoic patient are
making a comeback at the operating table.
A nibble from one of these creatures, whose closest relative is the
earthworm, can save limbs and even lives, say doctors who consider leeches
to be a valuable aid in microsurgery.
The unusual breakthrough came after US physician Dr Roy Sawyer
became convinced that the bloodsuckers, so widely used by doctors in
former times, had something to offer modern medicine. He set up a small
leech farm as a cottage industry in his home in Swansea, Wales.
Dr Sawyer and his team hit upon a proven use for these creatures.
Applied to wounds caused by accidental amputations, leeches can play an
important role in helping a reattached limb knit back together.
The tiny animals that Measure between 5 cm and 7 cm in length, are used
to remove congealed blood and prevent circulation blockages. "If someone
cuts their finger off in an accident, and a surgeon re-attaches it, the arteries
are relatively thick, so there is no problem there. But the veins are so tiny,
and, if they have been damaged during amputation, they are very difficult to
reattach," explained Gower, manager of Biopharm in Wales. As a result,
although blood can flow into the re-attached limb via the arteries, it cannot
flow back out again as it should do, via the veins. The blockage soon causes
the re-attached part to go black and develop gangrene, and eventually it has
to be re-amputated. This is where the leeches are introduced. They have a
natural anti-coagulant in their saliva which keeps the blood flowing and
restores circulation. As soon as the limb develops a bluish tinge, the surgeon
knows that he must act quickly. "That's the signal that the leech must come
in," said Gower.
Once latched on, the creature will feed on the
blood of the patient for about 20 minutes before it
drops off, satiated. The wound it leaves will bleed
for another 10 hours. This keeps the blood flowing
into the attachment and out again, causing artificial
circulation within the limb or finger. All this call be
done by resorting to drugs.
The treatment may sound gruesome, but it is
rapidly gaining acceptance in the medical world.
Leeches are now used in all major plastic surgeries,
as well as in burns and reconstruction units in
Britain in more than 100 hospitals.
The number of leeches needed depends on the size
and severity of the wound. As many as 200 of the
small bloodsuckers, which cost about US$6
each, can be necessary to save a severed
Like any instrument that comes into contact with
blood in a medical setting, the bloodsuckers have to
be disposed of after use, in order to avoid the risk of
passing oil infection or diseases such as AIDS. When
their last meal is over, they are humanely killed.
Leeches that are used have been on a starvation regime for at least six
months. That is not cruel as it sounds. A leech can easily go for a year or 18
months without food. "Obviously, it is no use sending out a leech that is fed,
because it simply would not be interested," said Gower.
The first recorded use of leeches for medical purposes was in India in 1000
BC. Down the centuries, leeches have been used to treat headaches, gout and even
madness in patients as illustrious as Stalin, Napoleon, and George Washington.
Leeches are fast becoming accepted in the medical world. While patients may find
the idea gruesome and turn pale on hearing about the
treatment in store for them, there is no doubt they will not refuse it if they
are forced to choose between losing a limb, a nose or ear, or just having a
couple of leeches feed on them for 20 minutes.