Key Insights On Advanced Wound Care Treatments
- Volume 23 - Issue 3 - March 2010
- 9715 reads
- 0 comments
A: Along with his Japanese collaborators, Dr. Suzuki has tried autologous stem cell injections in ischemic lower extremity wounds. Although the profession does know that such injections often help relieve the ischemic wound pain, he says definitive data on wound healing or angiogenesis has yet to emerge. He feels it will be a few more years before the development of evidence-based treatment protocols on autologous stem cell injections.
When it comes to platelet rich plasma (PRP) centrifuge systems, Dr. Suzuki says such technology is promising. However, he urges caution until these modalities have solid evidence behind them.
“I believe we have to be critical when evaluating these ‘new and exciting’ therapies,” maintains Dr. Suzuki. “Until we can develop evidence-based wound care protocols using new biologic products such as PRP, I prefer to stick with proven ‘best care’ wound care therapies such as surgical debridement, VAC therapy and hyperbaric oxygen therapy.” Dr. Suzuki also notes that PRP and stem cell therapies are considered “experimental” and are largely non-reimbursable.
Dr. Travis says PRP is comprised of an assortment of autologous growth factors that synergistically improve wound healing. As he expounds, the mixture of concentrated autologous platelets with calcified thrombin cause a secretion of serotonin, fibronectin, platelet derived growth factor (PDGF), platelet-activating factors and other growth factors. Dr. Travis explains that these factors induce a chemotactic response and process a migration of endothelial cells, which increases angiogenesis, osteogenesis and the formation of granulation tissue.
In wound care, Dr. Travis cites the effective use of cellular and acellular wound matrices, including live keratinocytes, fibroblasts, collagen, glycosaminoglycans, proteins and various growth factors. Dr. Travis has used PRP with several wounds in which he has incorporated grafts such as Apligraf (Organogenesis). He selects patients for this therapy if they have connective tissue diseases such as scleroderma and wounds that typify a delayed healing environment. However, Dr. Travis says most wounds would benefit from this therapy.
“It appears that incorporating the stem cell therapy of PRP allows the cellular signaling molecules to direct the stem cells to fill the gaps, restoring the entire tissue compartment to the wound bed,” offers Dr. Travis. “Successful incorporation of the graft matrix to the recipient site is key in healing these difficult wounds.”
Both Dr. Travis and Dr. Suzuki cite the use of becaplermin (Regranex, Systagenix) PDGF gels in accelerating the wound healing. However, Dr. Suzuki notes that the treatment protocol is somewhat demanding (once a day application and the need for refrigeration). He adds that not all his diabetic foot wound patients may be candidates for Regranex gel. Dr. Lavery adds that Regranex is expensive and its clinical efficacy “has not seemed to live up to” the randomized controlled trials.
Most skin substitutes — such as Apligraf, Dermagraft (Advanced Biohealing) and Oasis (Healthpoint) — contain various growth factors, and Dr. Suzuki considers them as “growth factor supplementation” in some patients. He notes the availability of dozens of new skin substitutes from human cadaver and bovine and other animal sources for wound healing and tissue augmentation. Dr. Suzuki adds that this “competition is always good” for doctors and patients.
Dr. Travis notes the recent emergence of gene and stem cell therapies as promising approaches for chronic and acute wound treatment. He cites the widespread clinical applications of stem cell therapy.
However, Dr. Lavery is skeptical. “Stem cell therapies are still not ready for prime time,” he says. Although there is one study at the University of Miami on stem cells for wounds, he notes there are no commercially available products.