Laying down a matrix: ECM dressings offer proactive approach to chronic woundcare

March 1, 2009

Extracellular matrix wound dressings can help give chronic wounds a jump start by applying living cells to the wound base and helping to stimulate healing.

Key Points

Milwaukee - Extracellular matrix (ECM) dressings are gaining favor in chronic wound repair as a proactive means of giving the dermal matrix a much-needed boost when a host of issues prevent it from sufficiently stimulating healing on its own.

ECM dressings work by providing living cells to the wound base, and in doing so, they can be essential in the otherwise difficult healing process of chronic wounds, says Jeffrey A. Niezgoda, M.D., medical director, Centers for Comprehensive Woundcare & Hyperbaric Oxygen Therapy and Aurora Healthcare Hyperbaric & Woundcare Associates, Milwaukee.

"The idea is to provide an extracellular matrix to the body that will assist in helping move the wound through the proliferative phase and on to healing," Dr. Niezgoda tells Dermatology Times.

Specific issues stand in the way of chronic wound healing, including fibroblasts that are either deficient in their signaling or response mechanisms, are deficient from a numbers standpoint, or simply are not functioning at all, Dr. Niezgoda says.

The matrix laid down by ECMs can, meanwhile, help with the formation of granulation tissue and bring about epithelialization and, ultimately, healing.

Popular ECMs include Promogran and Prisma (both Johnson & Johnson), as well as the animal-sourced Oasis (Cook Biotech Inc.), a collagen made from porcine small intestinal submucosa.

Study

A study sponsored by Cook Biotech concluded that Oasis potentially has multiple functions in helping with wound healing, including the ability to absorb, retain and protect bioactive molecules from the wound environment (Adv Skin Woundcare. 2007 Oct;20(10):541-548).

"My experience is that we apply Oasis once a week and it's convenient, because you don't have to reapply every day," Dr. Niezgoda says.

Allogenic products

When it comes to extracellular matrix dressings, however, researchers are beginning to focus on allogenic, or human-source, products, which they are finding have some important advantages over animal-sourced dressings.

"Much of the research in the area of ECM dressings now is heading in the direction of allograft products, which are proving to cause much less reactivity, inflammation and scarring in the wounds than with animal-sourced extracellular matrix dressings," Dr. Niezgoda says.

Dr. Niezgoda adds that he has had much success with GraftJacket (Wright Medical Technology), a matrix made from donated human skin. According to Wright Medical's Web site, the product allows cellular repopulation and revascularization by "preserving human dermal tissue, including its native protein, collagen structure, blood vessel channels and essential biochemical composition."

A big advantage of a product like GraftJacket is that instead of weekly - or more - changes of dressing, the product, in some cases, may need just one application, Dr. Niezgoda says.

"Depending on how the matrix responds, it's possible that a second application is not required with GraftJacket," he says. "You can lay it down and let it dry, and it turns into sort of a scab."

And while the current emphasis on chronic wound healing is to keep the wound moist, GraftJacket can help heal the wound by actually forming a scar.