Mix the Eye of Newt...
... three leeches, the liver
of a toad and the toenail of a bat. Boil until thick. Drink the potion under a full moon at midnight.
If you guessed that the recipe above comes straight out of a sorcerer's book of remedies, you're right. And, of course you know that using any of those ingredients for medicinal purposes today is totally absurd, right? Well, not exactly.
Believe it or not, leeches - technically known as Hirudo medicinalis - have found a very respectable place in medicine. They are being used more and more in micro-, plastic and reconstructive surgery. Marek K. Dobke, MD, program director and chief of reconstructive surgery at UMDNJ-New Jersey Medical School, says he's used this ancient treatment two or three dozen times in the last year. The leeches relieve blood congestion that can kill tissue, he says, and are especially useful when reattaching flaps of skin, severed ears, lips, fingers and toes. "Usually we can reconnect major veins and arteries," the surgeon explains, "but the micro-vessels must repair themselves. The leeches help prevent gangrene by draining the pooled blood, while the vessels heal."
A window is cut in a patient's dressing, Dobke says, and the invertebrate is applied. The "vampire worm" starts out a little less than two inches long. When its feast is completed, it's about five times its normal size and resembles a small cigar. Once engorged, the leech falls off. If needed, another one replaces it. Because the leech secretes an anticoagulant known as hirudin, blood may continue to flow for as long as 10 hours after it drops off.
The leeches used in hospitals look exactly like any other; however, they are not just run-of-the-mill night crawlers. Breeders raise them on special farms, using a process that is a carefully kept secret. The people at Leeches USA - UMDNJ's primary supplier of leeches, located on Long Island - will only say that breeding leeches is very involved. "They are not fed before they're shipped," says Dobke. "When they arrive, they are empty and very hungry. They can feed sometimes for as long as an hour." The cost of one leech is about $7.
Dobke says he can't remember ever having a patient who balked at the use of leeches. "They may be a little stunned at first," he says, "but because most have been through a trauma, they are willing to do whatever it takes to recover."
Leeches do harbor bacteria in their mouths that can cause infections, so patients are given antibiotics as part of the treatment. Even with the threat of infection, Dobke says leeches are the best treatment for micro-vein repair. Unlike drugs, they can be applied exactly where they are needed and they willingly do the job quite well.