Dressing Update

Collagen Dressing

Collagen is the most abundant protein in the body. There are 28 subtypes of collagen that have been identified and 3 subtypes that are specific to skin its underlying structures (i.e. tendon and bone) and wound healing (type 1, 3, and 4). Collagen is an important component in all the phases of wound healing. Collagen dressing has become a key dressing for the treatment of chronic wounds.

Chronic wounds have many factors that can be significant contributors to their presence. Chronic wounds receive their designation when they do not heal as fast as expected or respond approximately to indicated therapy. Wounds become chronic due to various types of stressors. These stressors include the presence of necrotic tissue, the presence of slough, the presence of bioburden or biofilm, the presence of localized ischemia, repeated trauma to the wound site, the presence of infection, etc.

In many cases chronic wounds are stuck in the inflammatory phase of wound healing. During their stasis within the inflammatory phase, an over expression of an enzyme called matrix metalloproteinases (MMPs) occur. MMPs are responsible for degrading non-viable collagen that remain on the surface of the wound bed. But when a wound is stuck in the inflammatory phase, MMPs are over-expressed and they not only begin to digest non-viable collagen on the surface of the wound bed but also viable collagen. This will further contribute to the chronicity of the wound and prevent its progression into the proliferative phase. For chronic wounds that are stuck in the proliferative phase its been discovered that they the fibroblast cells do not produce enough or any regulatory inhibitors to MMPs appropriately. These inhibitors known as tissue inhibitors of MMPs (TIMPs) are normally produced during the proliferative phase to help regulate the activity of MMPs which in turn allow for the healthy production of extracellular matrix (ECM) and granulation tissue formation.

Collagen bases wound dressings (which come in pads, powders, pastes and gels) provide the unique benefit of redirecting MMPs when added to a wound bed. MMPs begin to digest the dressing, there by allowing the body to regenerate its own healthy collagen. This then leads to the progression of the wound through the normal phases of wound healing again. In addition, the collagen dressings add to the bodies own healthy collages in the production for the ECM and new granulation tissue.

This dual benefits makes collagen dressings a key player in the treatment of chronic wounds.

Collagen dressings can come treated with ethylene diamine tetraacetic acid (EDTA), which acts as a chelating agent to destroy the MMPs once they attempt to digest the collagen dressing. Collagen dressing can also come infused with silver(Ag) for an additional antimicrobial benefit.

Additional benefits of collagen based dressing: