Key Insights On Treating Burn Wounds In The Lower Extremity

   Treating partial- and full-thickness burns present unique challenges for podiatrists. Although one may need to refer burns to a burn center, there are measures DPMs can take to treat burns and help relieve the patient’s pain. Accordingly, these expert panelists discuss their preferred modalities for wounds, methods of management and their thoughts on the role of bioengineered tissues and oral antibiotics.    Q: What is your initial management of lower extremity burn wounds as far as partial-thickness (second degree) versus full-thickness (third degree) burns?    A: When it comes to burns, especially those in compromised patients, Gerit Mulder, DPM, cautions that one should refer these patients to a burn center. In regard to partial thickness wounds, Dr. Mulder says podiatrists should use an appropriate wound cleansing agent. He adds one can usually treat such burns successfully with various agents depending on the wound depth and presentation. Dr. Mulder suggests using Collagenase (Smith & Nephew), silver sulfadiazene (Silvadene, Monarch Pharmaceuticals) or Xeroform. He also says one may use Acticoat (Smith & Nephew) on burns with clean wound bases and low to moderate exudate levels.    When treating partial thickness burns, Stephanie Wu, DPM, says one should cool the burn under cold running water for about 15 to 20 minutes, long enough to reduce pain, and follow this with cold compresses. She cautions DPMs to avoid applying ice directly to the burn. For a more severe burn, Dr. Wu will subsequently apply bacitracin or neomycin ointment. She follows this with loose bandaging, which keeps air off the burn and reduces pain.    Dr. Wu notes she tends not to drain the blisters and acknowledges this is a controversial topic. She frequently prescribes nonsteroidal antiinflammatory drugs (NSAIDs) for pain relief.     “Partial thickness burns are at a low risk for infection, unless they are grossly contaminated, so I do not prescribe prophylactic antibiotics,” explains Dr. Wu.    Full-thickness burns require excision and grafting, which are best left to the burn surgeon, according to Dr. Mulder. Dr. Wu agrees that early surgical excision and grafting will be needed.    In the case of a full-thickness burn, Dr. Wu gently washes the wound to remove loose char and tissue. If the patient is not allergic to sulfa, she applies Silvadene to the burn area and subsequently adds a loose bandage. For a patient who is allergic to sulfa, Dr. Wu uses either another preparation containing silver or a triple antibiotic ointment. She points out that full-thickness burns are at a higher risk for infection due to the presence of dead tissues and lack of blood flow. However, Dr. Wu does not prescribe prophylactic antibiotics unless the burn’s surface area is high.    Q: Is there any role for the use of Silvadene?    A: Dr. Wu says research has shown Silvadene to be an effective agent in treating burn wounds contaminated with Pseudomonas aeruginosa and is an accepted topical treatment for burns. However, she notes concerns about the potential for silver toxicity when one uses Silvadene in patients with extensive burns. Dr. Wu also expresses concern about the product’s efficacy in rare cases of sulphadiazine-resistant bacteria. Dr. Wu usually reserves Silvadene for full-thickness wounds or deeper partial -thickness burns.     “Silvadene is still a very acceptable topical antimicrobial agent for burn injury,” says Dr. Mulder. “The primary purpose of Silvadene is to reduce the risk of colonization progressing to true clinical infection.”    He notes patients would usually reapply the product twice a day in the in-patient burn setting and notes that one still needs to observe the wound closely.    Q: What topical wound products do you prefer in treating lower extremity burns?    A: As Dr. Mulder emphasizes, he refers most of his patients, especially those with full-thickness burns, to a burn unit. However, when treating more superficial burns, he bases the choice of topical wound product on the wound depth, its appearance and the underlying medical status of the patient. His treatments of choice include Collagenase, silver sulfadiazene and Xeroform.    As for Dr. Wu’s choice of topical wound products, she utilizes Silvadene, a triple antibiotic ointment and mafenide cream (Sulfamylon, Mylan Laboratories). She notes she has also used other silver-containing topical preparations and dressings including Acticoat, which permits fewer dressing changes.    Q: Is there any role for bioengineered skin substitutes?    A: Although bioengineered tissue has a role in treating burn wounds, Dr. Mulder says that role is usually more limited in the burn patient versus the chronic wound patient. He says one would usually debride full-thickness burns in the operating room. After achieving a healthy wound bed, Dr. Mulder says grafting is a standard procedure. Depending on the depth of the wound, he says clinicians may use additional products to assist with adequate granulation of the wound bed before placing a split-thickness skin graft. Trans-Cyte (Advanced BioHealing) and Integra (Integra Life Sciences) are helpful for this purpose, according to Dr. Mulder.    When treating full-thickness and deep partial-thickness burns, Dr. Wu notes that autologous skin grafting is the gold standard. However, she adds that practitioners may alternatively use bioengineered skin substitutes with good results. As Dr. Wu points out, research has shown bioengineered skin substitutes help heal partial-thickness wounds faster than topical preparations.    Q: What role do oral antibiotics play in the management of burns? Is there any prophylactic role? What are the most common pathogens?    A: With the exception of expansive burns, Dr. Wu says prophylactic antibiotics are rarely necessary. Dr. Mulder concurs, noting that prophylaxis is not a common practice for burn wounds at his facility. Dr. Wu says regular wound care with topical antibiotics has been shown to be effective in reducing wound sepsis.    Although Pseudomonas aeruginosa is the predominant burn wound pathogen, Dr. Wu says some patients may also develop fungal infections. She notes that previous studies have noted a significant association between increasing burn size and an increasing incidence of gram-negative invasive organisms.    Dr. Mulder notes one should differentiate invasive pathogens from wound colonizing organisms via quantitative cultures. One would usually obtain such cultures following the excision of non-viable tissue in order to obtain more accurate results. Although Staph aureus and Pseudomonas are the most common bacterial isolates, clinicians may isolate other gram-positive and gram-negative organisms, according to Dr. Mulder. Dr. Mulder is an Associate Professor of Surgery and Orthopedics at the Department of Surgery/Division of Trauma at the University of California-San Diego (UCSD). He is also the Director of the Wound Treatment and Research Center at UCSD. Dr. Wu is the American Podiatric Medical Association/American Diabetes Association Senior Fellow at the Center for Lower Extremity Ambulatory Research (CLEAR) at the William M. Scholl College of Podiatric Medicine at Rosalind Franklin University of Medicine and Science in Chicago. Dr. Karlock (pictured) is a Fellow of the American College of Foot and Ankle Surgeons, and practices in Austintown, Ohio. He is a member of the Editorial Advisory Board for WOUNDS, a Compendium of Clinical Research and Practice.