A horse in respiratory distress or displaying other signs of airway ailments warrants a prompt call to the veterinarian; he or she has tools and experience to attempt to resolve the problem. At the 2011 American Association of Equine Practitioners Convention, held Nov. 18-22 in San Antonio, Texas, Brett Woodie, DVM, MS, Dipl. ACVS, a surgeon and owner at Rood & Riddle Equine Hospital, in Lexington, Ky., described several suggested treatment methods for common upper respiratory tract ailments.
In a previous lecture, he discussed different techniques veterinarians can use to evaluate upper respiratory tract abnormalities.
One of the most versatile treatment options for upper respiratory tract ailments involving potentially life-threatening obstructions or respiratory distress is a tracheotomy, which involves making an incision through the front of the neck into the trachea. While tracheotomies often are used to create a direct airway in emergencies (and in such cases, the earlier the better), Woodie said a planned tracheotomy can help treat some upper respiratory ailments.
Tracheotomies can be used to treat:
- Bilateral arytenoid chondritis (inflammation of both arytenoid cartilages that results in severe obstruction of the upper airway);
- Bilateral laryngeal paralysis (which prevents either arytenoid cartilage from opening, causing an obstruction at the entrance of the trachea also known as "bilateral roaring");
- Severely enlarged retropharyngeal (throatlatch area) lymph nodes (commonly caused by strangles); and
- Guttural pouch tympany (an overfilling of one or both guttural pouches with air).
Tracheotomies afford the airway to "rest" if a horse is suffering respiratory distress. A veterinarian can perform the procedure in a horse that’s standing, under general anesthesia, or collapsed (when the horse "passes out" from a lack of oxygen), he explained.
Woodie cautioned that in some cases, horses with airway obstructions become "violent while in severe respiratory distress" and dangerous to handle. In these situations he recommends allowing the horse to collapse before quickly performing an emergency tracheotomy to restore oxygen flow to the lungs.
Once a tracheotomy tube is in place, aftercare is relatively straightforward, Woodie said. The most important parts of aftercare are ensuring that the tube does not become obstructed with secretions from the trachea, and that the skin surrounding the incision remains clean and healthy.
Potential tracheotomy complications include tracheal collapse, altered pulmonary defense mechanisms, and cellulitis (inflammation of the skin tissues) around the tracheotomy incision.
Woodie explained that veterinarians mainly use formalin to treat a progressive ethmoid hematoma (slowly expanding masses that originate from the mucous lining of a structure called the ethmoid turbinate, located in the back part of the nasal cavity). Injected directly into the mass, formalin essentially causes the tumor to slough, eliminating it.
While aftercare for an intralesional formalin procedure is fairly minimal, Woodie said, most lesions require more than one treatment. He explained that fairly heavy drainage from the patient's nose is normal post-injection.
Additionally, veterinarians using formalin should use caution when administering the solution, as it can be dangerous to humans. "Formalin is highly irritating to the respiratory tract and skin," he explained. "Contact with the eyes can cause permanent loss of vision."
Woodie explained that sinocentesis is a procedure by which a veterinarian drills a hole into a horse's sinus cavity and collects a sample for microscopic evaluation. Veterinarians often use this procedure on horses with suspected sinusitis. Typically a sinus lavage (flush) is carried out at the same time to "evacuate infected material from the paranasal sinuses," he said.
"The primary means of accessing the sinuses is trephination, which allows limited access to the paranasal sinuses but can be used as a procedure for aspiration and irrigation in the standing, sedated patient," Woodie said.
Respiratory tract and sinus problems are treatable conditions in horses and, with a veterinarians' help, most horses can make a full recovery, assured Woodie.
"These treatments can be used by veterinarians in the field as well as in the hospital setting to address upper respiratory tract problems that a horse may experience," he concluded.
Disclaimer: Seek the advice of a qualified veterinarian before proceeding with any diagnosis, treatment, or therapy.