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EQUINE HEALTH
“Even though the burns look terrible, what will immediately kill the horse is either life-threatening shock associated with the burn, and/or the respiratory distress that is usually associated with smoke inhalation.” – Dr. Reid Hanson
TREATING A SERIOUS BURN
“Third-degree burns are the ones that are potentially life-threatening, and the horse must be treated for shock and/or respiratory distress as a first priority. Even though the burns look terrible, what will immediately kill the horse
is either life-threatening shock associated with the burn and/or the respiratory distress that is usually associated with smoke inhalation.” The resultant swelling in the air passages may close off the airways and the horse suffocates.
A third-degree burn goes clear through the dermis - the bottom layer of the skin, into deeper subcutaneous tissues. “This leaves a primary collagenous structure, the eschar, which is almost like a bandage itself. We don’t recommend removal of this eschar. Therefore, open wound treatments for extensive burns in horses are not practical, unlike what they do in people—because there’s more likelihood of environmental contamination and massive loss of fluids
and body heat due to exposure of all that unprotected tissue,” he explains.
“The most effective and practical therapy
for third-degree burns in horses is to leave the eschar intact, with two to three times a day application of anti-bacterial agents right on the wound. So, we clip the surrounding hair and debride (remove) the dead, burned tissues. If we are at the scene immediately after the horse is burned, we cool the burn with ice or a cold- water bath, and do a lot of lavage with a weak, sterile chlorhexadine solution. This is what you can do in the first hours to cool the skin. But too much water applied to the skin will actually do more harm by increasing formation of edema in the skin,” he says.
“After we’ve debrided the tissue, clipped
the hair, and figured out approximately where the burn is, we apply a water-based antibiotic ointment very liberally over the affected areas to prevent heat and moisture loss and to protect the eschar. This will also help prevent bacterial invasion, infection of the wound, and potential septicemia,” he says. As time goes on, these applications also help loosen any necrotic tissue and debris.
“This is a slow method of continuing debridement, allowing removal of all the necrotic tissue, and thereby preventing possible removal of healthy germinal (growing) layers by mistake,” he explains.
The eschar is allowed to remain intact as a natural bandage until it is ready to slough off on its own.
You can’t prevent bacteria from getting onto
a large wound, so it should be cleansed two to three times a day, applying the topical antibiotic ointment after each cleaning. “We usually use silver sulfadiazine. We don’t use occlusive dressings (closed, protective) like those used on people. We don’t use wet dressings or wrap them up with antibiotics. Occlusive dressings create a closed wound environment that may encourage bacteria to proliferate and delay healing,” explains Hanson.
“Sometimes we use a sheet soaked in chlorhexadine and drape it over the top line of the horse to protect burned areas over the back,
but we don’t do that very often—mainly just initially until we can see which layers are intact and which ones are not. That moisture in the first 12 hours helps us identify what needs to come off right away,” he explains.
“The Silvadine cream can be applied as a ‘bandage’ anywhere over the body. We don’t
use systemic antibiotics very much because they don’t favorably influence wound healing; there is not enough blood supply to those burned tissues. All you do by giving antibiotics is just promote resistant organisms moving in,” he says.
DEALING WITH SHOCK
Immediately after the burn, the important thing is to prevent or deal with shock. “If a
A horse will likely need intravenous fluid therapy if a third-degree burn exceeds 15 to 20% of the body surface area.
A third-degree burn goes through the bottom layer of the skin – the dermis, into deeper subcutaneous tissues.
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Courtesy of Heather Smith Thomas