Medicinal leaches have been used for thousands of years because of their unique ability to get blood circulating into damaged tissue. The specific purpose of the medicinal leach is to alleviate venous insufficiency, a phenomenon that is a particular problem for surgeons trying to reattach or reconstruct tissue from which veins have been severed.
While it’s relatively easy to reconnect arteries, veins are smaller and more difficult.
Leaches can, however, carry infection, bring on an allergic reaction and can prove costly over a period of time.
These factors inspired Patrick Cottler, a University of Virginia researcher, to spend the past several years trying to improve on nature. The result is a miniature vacuum pump with an array of hypodermic needles that is said to perform as well or better than leeches in restoring blood flow.
Cottler’s device began with a vacuum pump actuator, first developed by NASA. He added an array of hypodermic needles to the pump, and a small replaceable reservoir. The device, which resembles a 2-inch square plastic bandage, is run by an external power source.
When placed over newly sutured skin, the pump draws out pooled blood in the same way as a leech.
‘We’ve got a prototype that worked in a small animal model. Now, I’m waiting for a US National Institutes of Health small-business grant that will allow production of a smaller, more elegant-looking device, with a battery power supply,’ said Cottler. ‘Once we get that, we can move on to human trials and hopefully production in a few more years.’
Cottler expects that the ‘smart bandages’ will be made in various sizes to accommodate various sized wounds and that the overall price will compare favourably against the cost of treating patients with leeches.
‘The fact is, most clinics don’t keep aquariums full of leeches around,’ said Cottler, ‘having a device like this on the shelf, available immediately, has the potential to improve wound healing and reduce the length of hospital stays for many types of surgeries, not to mention being more acceptable to patients.’