Point-Counterpoint: Are Acellular Dermal Matrices More Effective Than Fibroblast-Derived Dermal Substitutes?
Citing the literature, enhanced sterility and ease of use, this author says human acellular dermal matrices are an effective option for wound care.
By Howard Kimmel, DPM
In today’s wound care market, the clinician has many choices of products. Both human acellular dermis and fibroblast-derived dermal substitutes require the patient to have adequate vascularity and be free of clinical signs of infection.
Fibroblast-derived dermal substitutes have become very popular over the past few years. Even though these products have a high level of evidence to show that they work, they have some disadvantages and limitations. For instance, one can apply fibroblast-derived dermal substitutes on ulcers that extend into the dermis but not through it. Also, in patients who have a Charcot deformity with a midfoot ulcer, fibroblast-derived dermal substitutes have not been tested. If there are any sinus tracts present, one cannot use a dermal substitute. Fibroblast-derived dermal substitutes are also contraindicated for patients who have sensitivity to bovine products while such patients can use human acellular dermis.
In spite of good wound care by means such as offloading, debridement, control of infection and maintaining a moist wound environment, there are instances in which exposed musculoskeletal structures prohibit the use of fibroblast-derived dermal substitutes.
There is also a limitation to when one can apply fibroblast-derived dermal substitutes. Depending on the product, the FDA requires that the wound be present for four to six weeks for one to use fibroblast-derived dermal substitutes.1 Lavery and colleagues published a study showing that wounds open greater than 30 days have a 4.7 greater risk of infection.2
In contrast, there is no limitation as to when one can apply human acellular dermis.
Key Insights On The Advantages Of Human Acellular Dermis
Human acellular dermis has been safely in use for over 20 years. The initial indication for the product was for burns. Physicians have not only used the technology in diabetic foot ulcers and venous leg ulcers but have also used it in plastic and reconstructive surgery, as tendon reinforcement, and in abdominal wall reconstruction. Human acellular dermis has shown promise in graft integration, host cell infiltration and revascularization of the acellular dermis. Depending on the Medicare local coverage determination, one application of human acellular dermis can occur in the office.
Human acelluar demis is harvested from heavily screened donors. The tissue processing is in accordance with the American Association of Tissue Banks under FDA requirements. The current guidelines published in 2000 deal with implementing a program of “Current Good Tissue Practice.”3 Specifically, section 1271.230b states that “sterility should be based on a validated process.”
The Association for the Advancement of Medical Instrumentation, a standards-setting organization for the medical industry, defines the sterility assurance level (SAL) as the probability of an item being non-sterile after it has been exposed to a validated sterilization process to achieve a SAL of 10-6, meaning that there is less than a 1 in 1,000,000 possibility of a contaminating organism surviving the treatment.4 The process of sterilization differentiates the human allograft products. It is important to look for products that use the highest level of sterilization. Products that are aseptically processed do not achieve this level of sterility.