Page 111 - April2020.indd

EQUINE HEALTH
“Every horseman should have a stethoscope and know how to use it. You also need to know what your horse’s normal heart rate and respiration rate is and listen to bowel sounds.”
traditional wisdom is to keep him on his feet, if possible. Violent rolling, especially if the
gut is distended by gas with part of it too full and part of it empty, can cause it to flip over on itself, creating a fatal twist that shuts off blood supply to the gut. A normal horse with normal gut fill, rolling to rid himself of flies or scratch his back or relieve itchiness from sweat after a workout, will never suffer a twisted
gut. Violent rolling when the gut is already compromised is what can lead to problems, so the goal is to keep the colicky horse on his feet. This is usually accomplished by keeping him moving—walking him around until the vet- erinarian gets there to more fully diagnose the problem and hopefully resolve it with appropri- ate treatment.
One of the primary techniques used by veterinarians for colic diagnosis is palpation per rectum. The veterinarian gently reaches into the rectum with a well-lubricated plastic glove/sleeve, to try to feel some of the adjacent portions of the digestive tract and other organs to help determine what is going in inside the horse.
As stated by Cid Hayden DVM, this procedure is not without risk and should never be attempted by an untrained person. The rectal tissues of a horse are delicate and bowel contractions are very strong. “The horse may be jumping around and straining against the intruding arm. This, plus the delicate tissues, could lead to injury of the rectal tissues,” he says.
“If done correctly and carefully, the risk is minimal, but there is always a chance for mild irritation and inflammation of these tissues, or even rectal tears,” explains Hayden. “Those can be very serious, requiring emergency abdomi- nal surgery to correct.
“In a horse that has colic, the risks are greater. The horse already has abdominal pain and may have a lot of pressure due to a distended bowel. There may be an impac- tion, or a sore spot that would cause the horse to react if you bump into it. If you are palpating a horse for a colic examination, you could run into more potential problems, as well as more difficulty in doing the palpation itself.” he says.
“When trying to check the internal areas of the abdomen, no one has an arm long enough to feel the entire abdomen of a horse. You are
usually palpating the rear one-third at best. You can’t feel everything that you need to check. You are trying to feel for an abnormal- ity or for a normal organ that’s not where it’s supposed to be.
“In those situations, it’s not so much that you can feel what’s wrong, but the normal anatomy is not where it is supposed to be—or if it’s missing, where did it go?” says Hayden. The veterinarian may be able to interpret certain displacements.
“Some of the examination for colic, per rectum, trying to figure out what is wrong inside the horse, takes a lot of interpreta- tion—based on what the normal anatomy would have been. In a small practice like ours (more than 100 miles from an equine hospi- tal), if it’s a serious case where the horse needs surgical correction, this means hauling the horse somewhere else. Often, I am trying to decide early on if surgery (or a lengthier and involved diagnostic procedure) is needed, and also I have to determine if this is something the horse owner would want to do and could afford. We have to make these determina- tions as quickly as possible to give the horse a chance,” Hayden explains.
In a more elaborate hospital setting, colic diagnosis may include a laparoscopic exami- nation or flank surgery, or major abdominal surgery. Other techniques available at a larger clinic may include ultrasound, as well. But
out in the field or at a small clinic, tools and techniques are often limited to things like trans-rectal palpation, listening to gut sounds with a stethoscope, and doing a belly tap.
The basic examination will include checking heart rate, respiration rate, capillary refill time (checking the gums), etc., to see how shocky the horse may be.
“Color of the gums and mucous mem- branes and other color changes can also be clues regarding whether the horse is becom- ing toxic from endotoxin release or other problems,” says Hayden.
Listening to the abdomen with a stetho- scope can reveal the presence or lack of gut sounds, their frequency and the type of sounds. “A horse that has no gut sounds means that things are shut down, which is not a good sign,” he explains.
A belly tap (sticking a sterile needle through the belly wall to obtain fluid to examine) can tell the veterinarian several things. “We check for white blood cells and inflammatory cells, fibrin, etc. We can do other tests on that fluid to get an idea about how serious the horse’s condition might be,” Hayden says. A thorough examination of a colicky horse consists of many little bits of information to put together to see the larger picture.
One of the things the veterinarian will ask is whether the horse is passing manure. A horse with colic may pass a little manure at first
A horse with mild abdominal pain may stretch or stand with his head high and front legs forward, with hind feet farther back than normal, trying to ease discomfort or gas pains in his abdomen.
SPEEDHORSE April 2020 109