NCDCTA News/Ask the Experts – March 2010

Q: A friend recently dislodged a stick from her horse’s throat to prevent him from choking. She apparently saved the horse. But in the process, her fingertip was crushed beyond repair. For those of us who would like to keep all ten fingers, can you provide some sort of guidelines in case we run into a similar problem with choking? Sincerely, Guitar-Picker in Asheville

A: Dear Guitar-Picker,
Most of us would consider your friend very brave. I doubt that you will see most veterinarians putting their hands deep into a horse’s mouth without some means of keeping the mouth open, such as an oral speculum. It would probably have been more prudent to have called a veterinarian to have the stick removed. In an emergency, it is possible to put your hand into a horse’s mouth if you use the back of your hand to push the tongue between the upper and lower arcades, or pulling the tongue far to the side, (hopefully/optimistically) preventing closure of the teeth.

I think we have two different scenarios to discuss here. The first is the problem with a stick caught in the back of the throat. This could cause serious problems if the pharynx, esophagus or trachea is lacerated or punctured resulting in infection and marked swelling resulting in difficulty swallowing or, less commonly, breathing. These problems would take a few days to develop giving the horse owner time to have a veterinarian out to remove the stick and start the horse on antibiotics and anti-inflammatory medications.

The second scenario is choke. Choke in the horse is secondary to obstruction of the esophagus, not the trachea as seen in humans. Therefore, horses with choke do not have trouble breathing. Signs of choke include watery saliva, with or without feed material, coming out of both nostrils. The horse may stand with its head and neck extended and may look distressed. We usually see choke soon after a horse is fed its grain or pellets. Horses may bolt their feed if they are very hungry or feel the need to eat too quickly because of competition (real or perceived) from other horses.

Treatment of choke is fairly straightforward. In many cases, taking away feed and water for 1-2 hours will sometimes allow for relaxation of the muscles of the esophagus allowing for spontaneous resolution of the obstruction. Tranquilizers such as acepromazine and xylazine can promote muscle relaxation. In all cases, you should call your veterinarian to get advice about the treatment of your particular horse. If the choke does not resolve spontaneously, a veterinarian should examine the horse. We use a nasogastric tube to try to relieve the obstruction using pressure from the tube and pulses of water. The BIG RISK of choke is aspiration of saliva causing pneumonia. Risk of aspiration pneumonia is a reason horse owners should not use a water-hose to dislodge a choke themselves. Horses that have had choke are usually treated with antibiotics and anti-inflammatory drugs. They should be closely monitored for development of pneumonia, including taking the temperature twice daily, monitoring for nasal discharge, cough and loss of appetite. A second risk of choke is necrosis of the esophagus from prolonged pressure of the obstruction. Therefore, horses with choke lasting longer than 24 hours are often referred to a medical or surgical hospital where general anesthesia and possibly surgery are used to relieve the obstruction.

Prevention of choke centers on keeping horses from bolting their feed. Feeding hay first to take the edge off of hunger, placing bricks or stones in the feed pan, and feeding anxious horses separately are a few management tools that can be used. In rare cases, esophageal stricture or thoracic mass/neoplasia may cause choke.

Sally Vivrette (DVM, PhD) is the owner of Triangle Equine Mobile Veterinary Services in Cary, NC. She started her practice in 2001 after serving on the faculty at NCSU College of Veterinary Medicine where she was head of the Equine Ambulatory Medicine service. She is Board Certified in large animal internal medicine by the American College of Veterinary Internal Medicine and specializes in performance horses and preventive care. She competes in dressage with her 10-year old Hanoverian gelding, “Flash” and in low-level eventing with Susie Wiedman’s Swedish warmblood mare, “Mikhaila”. For more information, call (919) 460-6300 or go to www.triangleequine.com.