http://www.sfgate.com/cgi-bin/article.cgi?file=/c/a/2005/08/25/MNGCKECSOA1.DTL
FDA ponders leeches, maggots, old remedies making a comeback
Gardiner Harris, New York Times
Thursday, August 25, 2005
Washington -- Flesh-eating maggots and bloodsucking leeches were once
the tools of medieval doctors and shamans. But they have experienced a
quiet renaissance among high-tech surgeons, and for two days beginning
today, a federal advisory board will discuss how to regulate them.
Leeches, it turns out, are particularly good at draining excess blood
from surgically reattached or transplanted appendages. As microsurgeons
tackle feats like reattaching hands, scalps and even faces, leeches
have become indispensable.
Maggots clean festering wounds that fail to heal, as happens among
diabetics, better than almost anything in use, although the use of
maggots in the United States has been slight, in part because of
squeamishness.
But neither leeches nor maggots, despite their long histories of use,
have ever been subject to thorough regulation by the Food and Drug
Administration. So the medical advisers are being asked to create
general guidelines about how they should be safely grown, transported
and sold.
The meeting could be one of the last of its kind.
Since 1976, the agency has required that makers of medical devices
prove that their products are safe and effective. Those already on the
market had to prove their worth; those invented later had to get
approval before marketing.
But there are unexplored corners of the nation's medical market -- no
one knows how many, but they are certainly a vanishing few -- in which
doctors and manufacturers have been doing business since well before
1976 without much notice from the FDA. The making of maggots, leeches
and bone wax, another oddity being discussed, is one of those corners.
Bone wax -- made from beeswax, olive oil and phenol -- is commonly used
by surgeons to stop bones from bleeding or reknitting.
Officials first had to decide which part of the agency had oversight --
its biological or device division, said Mark Melkerson, acting director
of the FDA's division of general, restorative and neurological devices.
"The primary mode of action for maggots is chewing," Melkerson
explained. "For leeches, it's the eating of blood. Those are mechanical
processes." Thus, the agency decided that maggots and leeches were
devices, he said.
For centuries, physicians used leeches in the mistaken view that they
would help balance a patient's body fluids, or "humors." George
Washington is said to have died after physicians used leeches to drain
him of quarts of blood during an illness. With the development of
modern medicine, leeches fell out of favor.
But in the 1970s, leeches again became popular, this time with
microsurgeons.
When reattaching or transplanting an appendage, these surgeons are
often able to stitch together arteries, which deliver blood to the
appendage and are thick-walled and relatively easy to suture. Far
harder is finding and attaching veins, which collect blood for exit and
are smaller and more fragile.
With few veins connected, blood tends to engorge the new attachment
after surgery, clot, turn blue and -- in the worst cases -- kill it,
said Dr. L. Scott Levin, a Duke University hand surgeon. To buy time
for the body to create its own venous attachments, surgeons use
leeches.
Leeches inject victims with a potent chemical cocktail that includes an
anticoagulant, an anesthetic, an antibiotic and a chemical that dilates
blood vessels. This cocktail encourages fast bleeding to empty the
appendage of extra blood, reducing pressure and allowing veins to form
on their own.
In 20 minutes, a leech is usually engorged and removed. Bleeding from
the wound may continue for up to 24 hours. If an appendage is large,
several leeches are sometimes used at once, said Levin.
"I'll use one to three leeches every couple of hours," Levin said.
As for maggots, they are unparalleled in their ability to clean
festering, gangrenous wounds. For diabetics and others whose wounds
fail to heal, maggots -- pressed into dying flesh -- can save a limb
and speed healing.
Primitive tribes from Australia, the Hill Peoples of Northern Burma and
the Mayans of Central America were known to use maggots to clean
wounds. Napoleon's surgeon in chief noted their effects. During World
War I, a physician described seeing two soldiers who had been left
wounded on the battlefield for days. When they took off their clothes,
thousands of maggots were found in their wounds. Once the maggots were
removed, the physician was astonished to find clean, pink, living
flesh. This doctor, William Baer of Johns Hopkins School of Medicine,
became maggots' modern medical champion.
***
Their oversight of food and drugs has led us to a state where obesity
and disease is becoming overwelming and all they can come up with is
this kind of BS.
TC