Colic is a general term used to signify abdominal pain. It is a sign of a problem, not a diagnosis. Colic can be the result of a number of gastrointestinal or abdominal problems. Most often the problem originates in the colon, the large intestine, of the horse. However, colic can also be the result of a tumor, peritonitis, a variety of plant poisons, uterine tears, torsion of the uterus, renal problems, and others.
Some of the causes of colic respond to medical treatment, others can become fatal without surgical intervention. In domestic horses, colic is the leading cause of premature death. An estimated 4-10% of the horse population will die from complications of colic. A much larger percentage will suffer from colic at some time during their lifetime.
Many different types or causes of abdominal pain in horses are commonly described. They include; gas and spasmodic colic, impaction colic, displacement in the form of torsion and volvulus colic, intussusception colic, entrapment colic, inflammatory colic, ulcerative disease colic, foal colic, herniation colic, colic the result of uterine tears or torsions, as well as other possibilities.
Perhaps the most important signs of colic that should result in a call to your veterinarian are; anorexia (won’t eat), looking around at the abdomen, depression, sometimes grunting with pain, kicking at the abdomen with a hind hoof, sinking or falling to the ground and moderate to violent rolling on the ground. Because of the manner in which the gastrointestinal tract is suspended in the equine abdomen, and its weight, a horse rolling in pain on the ground is susceptible to a tear or twisting of the mesentery (the tissue from which the intestinal tract is suspended within the abdomen) through which the intestine can twist on itself resulting in torsion (twisting of the bowel on itself longitudinally through a tear in the mesentery) or volvulus (when a loop of intestine twists around itself vertically with the mesentery that supports it resulting in bowel obstruction). When this happens the blood supply to the affected intestine is blocked or cut off entirely leading to death of the tissue, gangrene and death without successful surgical intervention.
Because of the danger of a twisted intestine from rolling the first instruction your veterinarian will provide when contacted is to keep the horse up and walking. You need to do everything possible to not allow the horse to go down and roll.
To treat uncomplicated colic your veterinarian will generally start treatment with analgesia (pain relief), if the animal is very anxious perhaps sedation, then the insertion of a nasogastric tube. The nasogastric tube will relieve any gas accumulation in the stomach and possibly from the first portion of the small intestine and will be used to pump in intestinal lubricants, laxatives and sometimes surfactants to prevent further gas accumulation. If the colic is severe and the animal doesn’t respond to the initial treatments within a reasonable amount of time it may be necessary to support the horse with intravenous fluids and possibly with nutritional support. In severe cases treatment for endotoxemia (toxins produced in the gut) may be necessary.
We generally recognize the following major types of colic; excessive e gas accumulation in the intestine (gas colic), simple obstruction (impaction colic), strangulation (volvulus or torsion colic’s), non-strangulation or infarction colic (blockage of a blood vessel to the gut), inflammation of the gastrointestinal tract (enteritis or colitis), colic from peritonitis (inflammation of the peritonium, the lining of the abdomen), and ulceration of the gastrointestinal lining or mucosa (ulcerative colic). I will describe each of the various types of colic in future articles.