Stephanie Gross

Patrick Cottler is preparing to start his own company to market his invention -- the "smart bandage" he holds on his hand. The device acts like a medicinal leech, helping restore blood flow to a wound after surgery.

Improving on nature

By Charlotte Crystal

Leeches have been used in medicine for more than 3,000 years and Patrick Cottler thinks that's long enough.

Cottler, a doctoral candidate in biomedical engineering, has invented a mechanical leech he believes is superior to nature's blood suckers in several ways -- they are just as effective in drawing blood through traumatized tissue to reestablish blood flow, they don't migrate, they offer less risk of infection and they're less likely to disgust the patients.

To reestablish blood flow and promote healing after surgery, surgeons not only must reattach arteries to enable the oxygen-rich blood to flow into traumatized tissue, they must also ensure that the blood flows through and out of the tissue into reconnected veins. With plastic surgery in particular, reattached skin flaps present a challenge in reestablishing blood flow.

Medicinal leeches, or Hirudo medicinalis, are very effective in drawing blood through skin flaps when attached near the sutures, as far as possible from the blood inflow. Cottler's invention, which looks like a plastic box about two inches square, holds a series of hypodermic needles attached to a tiny vacuum pumping system that draws blood into a small, replaceable reservoir. The box is placed on the skin flap, with the needles puncturing the skin near the sutures. When activated, the vacuum pump draws blood through the skin flap and into the reservoir.

The invention won the Virginia Engineering Foundation's 1999 award for biomimicry, an annual contest for engineering students who design machines that mimic biological processes.

Cottler believes that his mechanical leeches -- to be called "smart bandages" for marketing purposes -- offer enough advantages to patients and hospitals that he is building a company around his technology even as he completes his studies and refines the technology itself.

"It's been very exciting designing a device with technology for an innovative lightweight vacuum pump actuator, originally developed by NASA, to bring an age-old treatment into the 21st century," he said.

Cottler expects to defend his dissertation this summer. In the fall, he'll launch Cottler Technologies LLC as a way to bring his idea to market. He already has filed a provisional patent application for the technology and is applying for a Small Business Innovation Research grant to develop a working prototype of his invention.

If that pans out, he plans to refine the device to work on battery power and advance to animal, and later, human testing.

After that, who knows? The company's name -- Cottler Technologies -- suggests there are more ideas where the mechanical leeches came from.