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EQUINE HEALTH
third-degree burn exceeds 15 to 20% of the body surface area, the horse will likely need intravenous fluid therapy. We don’t use really large volumes of lactated ringers IV therapy because of the possibility of over-hydrating the horse.” This might increase damage to the lungs if they’ve suffered from heat or smoke inhalation. If there’s very much edema in the lungs, the horse will have a serious problem.
“We use about 20 liters of fluid, maximum, in an adult horse. We also give Banamine
to reduce pain and inflammation and Pentoxifylline to help with circulation of blood through the vessels. We carefully monitor the horse’s hydration status, lung sounds, and cardiovascular status,” says Hanson.
“Depending on the horse and the amount of hypoprotenemia (low protein level) that develops, we may give 10 to 20 liters of plasma. In addition, we probably will give DMSO during the first 24 hours to decrease inflammation and pulmonary edema, pulling the fluid out of the lungs. If the veterinarian suspects that pulmonary edema is present and unresponsive to DMSO treatment, dexamethasone might be given—just once.”
RESPIRATORY DAMAGE
If respiratory signs or smoke inhalation is suspected - and most burns on the face will have smoke or heat inhalation injury, the horse is usually put on systemic antibiotics to treat the lungs. “Unlike burned skin, the lungs still have a good blood supply that can carry the antibiotic to the damaged areas,” he says.
“We usually put these horses on intramuscular penicillin if they have an uninjured area where we can inject it. This can help deal with contaminants that got into the airway, associated with the smoke. With smoke, there is soot—carbon—and it can
“Unlike burned skin, the lungs still have a good blood supply that can carry the antibiotic to the damaged areas,” – Dr. Reid Hanson
easily get into the lungs. The body then has
to eliminate all that carbon and the penicillin helps keep the horse from getting secondary bacterial infections. If respiratory signs worsen—respiratory rate increases, or the horse is coughing or can’t ventilate very well—then some lung fluid should be aspirated (trans- tracheal aspirate) to do a culture and sensitivity test to determine what other antibiotic might be needed,” says Hanson.
If there is smoke inhalation and the airways begin to swell shut after the fire, a tracheotomy may be required so the horse can continue breathing. “We only do this if we anticipate there will be some kind of obstruction. We generally do an endoscopy of the trachea after
a burn injury for prognostic purposes because there may be a lot of sloughing of the mucosa inside the airway. We try to aspirate that sloughed mucosa, but the aspiration procedure should last no longer than 15 second intervals because when you are aspirating material out of the trachea you are also aspirating oxygen out of it as well, making it harder for the horse to breathe,” he says.
“We may give the horse supplemental humidified oxygen through an intranasal catheter. We may or may not, depending on the horse, nebulize with albuterol, amakacin or acetylecysteine every 6 hours to help with antibacterial protection and to help slough
the necrotic tissue. Often, we’ll give systemic antioxidant therapy such as oral vitamin E and vitamin C. We may rinse the mouth out every 4 hours with a .05% chlorhexadine solution.”
DAMAGE TO EYES
With extensive burns, there may also be damage to the eyes. “We check for corneal ulcerations and eyelid burns. If the lids are swollen, we apply an ophthalmic ointment
to the cornea every 6 hours. We also check
twice a day for any evidence of further corneal ulceration. If the cornea is damaged, we very carefully debride the necrotic cornea after the horse is tranquilized and while using a topical anesthetic. We apply a topical antibiotic and atropine. We do not normally use steroids in the eye,” says Hanson.
“Occasionally a third eyelid flap may be needed to protect the cornea from severe trauma and damage (as from a necrotic eyelid). Then we can use silver sulfadiazine around the eye, but we need to be careful not to use chlorhexadine in or around the eye.”
NUTRITIONAL NEEDS
“As the horse is recovering from the burn— after we’ve gotten him through the acute things that could kill him, such as smoke inhalation and shock—we need to keep him nutritionally intact,” says Hanson. There’s a lot of healing to accomplish, and this takes more nutrients.
Metabolic rate increases in proportion
to the size of the thermal injury, especially
if it exceeds 10% of the total body surface area. This causes an increase in core body temperature and increases in oxygen consumption and protein/glucose utilization. “Caloric expenditure and protein breakdown are greater in burn injuries than in any other
Horses may be put on intramuscular penicillin if they have an uninjured area of muscle where it can be injected.
86 SPEEDHORSE October 2022