The approval of a new human amniotic membrane allograft is changing the lives of many patients who suffer from diabetic foot ulcers. Marketed under the name EpiFix®, the product is one of several skin substitutes available for treating these hard to heal wounds.
“Typically, decreased microvascular blood flow ultimately leads to impaired healing,” says Matthew Reed, MD, a surgeon at Medical West Advanced Wound Care Center in Bessemer. “Most of these patients develop neuropathy, and they wear pressure at prominent points on their feet. Because they can’t feel the pain, they continue to put pressure on their feet and tissue damage occurs.”
These type wounds generally don’t heal well because the skin has a hard time regenerating new tissue on its own. Even in cases where primary healing is achieved, ulcers frequently occur. Because EpiFix® is made from human amnion chorion membrane, it is an ideal treatment for diabetic foot ulcers. The allograft consists of multiple extracellular matrix proteins, growth factors, cytokines, and other specialty proteins present in amniotic tissue to help regenerate new soft tissue.
According to MiMedx, the company that makes EpiFix®, human amniotic membrane allografts have been used for a variety of reconstructive surgical procedures since the early 1900s. The amniotic membrane encapsulates the fetal compartments composed of amnion and chorion layers. The non-vascular tissues consist of epithelium cells, basement membrane, a thick compact layer, and a fibroblast layer. The fibrous layer contains cell anchoring collagen types I, III, IV, V and VII. Biochemical properties help to reduce inflammation and enhance soft tissue healing. Fresh amniotic membrane also has antibacterial and pain reduction properties.
The use of these allografts has increased because of the company’s Purion® Process, which allows the tissue to be dehydrated and sterilized. The process safely and gently separates placental tissues, cleans and reassembles layers, and then dehydrates the tissue to preserve the key elements associated with healing. It also removes blood components while protecting the delicate scaffolding of the amniotic membrane, leaving the extracellular matrix. The allografts can be stored for up to five years.
Studies have shown that EpiFix® enhances healing, reduces inflammation, and reduces scar tissue formation. “We have seen beneficial tissue growth with this skin substitute and fewer incidents of bacterial growth,” Reed says.
Prior the use of the skin substitute, Reed says the long-term standard was debridement of devitalized tissue, off-loading, and a host of different wound dressings designed to protect the wound. However, the dressings in and of themselves didn’t promote new tissue growth.
“With EpiFix®, we still debride devitalized tissue in the wound base initially, but typically there is much less need for drastic debridement with subsequent visits,” Reed says. “In order to meet approval guidelines, the wound has to be chronic (present for at least four weeks). Diabetic wounds and venous stasis wounds are the main ones that have approval for EpiFix® use at this time.”
The EpiFix® allograft comes in several different sizes. “We pick the size graft that is needed to fit the wound. It is placed over the wound with a protective dressing on top and anchored in place,” Reed says. “The dressing is changed every seven to 10 days. We have used EpiFix® for about a year and are seeing good results in cases where we have had trouble obtaining closure in prior treatments.”
EpiFix® has been approved by the Federal Drug Administration, Medicare, and most major insurance companies for use on diabetic foot ulcers and venous stasis ulcers. Reed says it also has been used in the operating room to support closure of wounds that might otherwise be at high risk for a breakdown.
“There are ongoing clinical trials involving EpiFix® that are looking at further indications for the use of this product,” Reed says. “It will be interesting to see if other indications arise that will gain FDA approval and insurance coverage for use in other areas of health care.”