What causes it?

As previously mentioned, a horse can exhibit colic signs for a large variety of reasons, and all body systems should be evaluated in the colicky horse. However, the most common and largest number of causes originate in the GI tract, which are outlined below.

• Gas colic - The most common cause of colic in the horse, luckily is also one of the mildest. This is when gas bubbles form in the GI tract, causing mild to moderate discomfort. This is often caused by changes in feed, changes in the weather and changes in routine.

• Impaction colic - Impactions occur when feed material becomes stuck along the digestive tract. This causes an obstruction, and blocks feed material from along the GI tract. This causes discomfort to the horse, as well as predisposes them to more severe forms of colic if the impaction remains. This is often seen in horses that are dehydrated, or if they have had a change in feed.

• Sand colic - This occurs when the horse ingests sand - usually because they have been eating their feed on sandy surfaces. The sand eventually settles in the lowest region of the GI tract where it causes irritation and obstruction.

• Displacements - This is when a portion of the digestive tract is displaced to an abnormal position in the abdomen. It is usually accompanied by an impaction, which is the cause for displacement of the intestine.

• Strangulating lesions - This is a very severe type of colic that involves cutting off of the blood supply to part of the digestive tract. The blood supply can be cut off by the intestines twisting on themselves, or by having a mass with a stalk, such as a lipoma, wrap around the intestine.

• Enterolithiasis - Enteroliths form when minerals in the horse’s own digestive tract form around a nidus, such as a wire, piece of hair, small piece of wood, small stone, etc. The mineral forms in layers, very similarly to a pearl. Enteroliths can become very large, and sit in a location where it does not cause a problem for years. But then, something can cause them to move and become lodged along the digestive tract. There is some breed predisposition for this, as it is seen more often in Arabians, Morgans and Miniature Horses; however, it can happen in any breed. Diet also plays a roll, with high alfalfa diets being more likely to cause enteroliths, and the southwest United States being over represented.

How is the cause of colic diagnosed?

As discussed above, “colic” is a clinical sign of a problem, and NOT a diagnosis. Because the horse has a GI tract that is especially prone to cause colic, it is often where the problem originates. However, to be sure of the origin of the problem, we will look specifically at your horse, starting with a thorough history and physical exam. From here, the following tests/procedures may be recommended to come to a diagnosis.

• Rectal palpation - by performing a rectal with our physical exam, your vet can feel for specific abnormalities within the abdomen. We can assess for abnormal anatomical placement of organs, feel for abnormal GI contents, palpate the urinary bladder, and reproductive tract, all giving valuable information regarding a potential origin for the problem.

• Passing a nasogastric tube - Passing of a nasogastric tube from the nose to the stomach can be helpful in aiding in diagnosing the problem as well as treatment. By passing the tube, we can evaluate the contents of the stomach, as well as administer oral fluid +/- electrolytes and other therapeutics.

• Blood/peritoneal lactate - this is a test performed off of a blood or peritoneal fluid sample. It is a general marker for anaerobic processes. In the case of colic with GI signs, a high lactate may indicate that the blood supply to a region of the digestive tract has been compromised.

• Ultrasound - we may recommend an ultrasound of the abdomen and thorax. The ultrasound performed in the field is generally called a FLASH ultrasound. This is a specific method where regions of common colic associated pathology can be evaluated.

• Complete Blood Count and Blood Chemistry - looking at a horse’s bloodwork can give information about body systems affected, indicators for infection, as well as electrolyte imbalances that may be necessary to correct with fluid therapy

• Surgery - sometimes the cause for colic can only be definitively determined with surgical intervention.

• And much more - diagnosis of the cause for colic is largely based off of the initial history, physical exam, and the results of subsequent diagnostics. For this reason, no colic gets treated exactly the same in regards to diagnostics - we have starting points, but continue our search based off of the previous results.

What are the treatment options?

Since the causes of colic vary greatly, so do the treatments. Since GI colic is most common, the most common treatments for GI colic are outlined below.

Therapy for GI colic can broadly be separated into two categories: Medical Management and Surgical Management. Depending on the severity of the colic and response to initial therapy, some horses will need minimal therapy and can be easily managed on the farm, while some will need very extensive medical attention, including hospitalization.

Medical Management includes but is not limited to:

• Nasogastric tubing - as mentioned previously, passing a tube from the nose to the stomach can provide both diagnostic information and therapy. Therapies that can be administered through a nasogastric tube include, oral fluids, electrolytes, psyllium, and a variety of other oral medications. It can also relieve gas and excess fluid that may be expanding the stomach, as horses can’t vomit on their own.

• Systemic NSAIDs - Flunixin meglumine, more commonly known as Banamine, is a systemic NSAID that is common given to reduce colic pain.

• Buscopan - a medication that reduces wave-like contractions of the GI tract, this will reduce the crampiness that your horse may be experiencing. Care should be taken when giving this medication, though, because there are some types of colic where it is preferred to not reduce motility/contractions of the GI tract.

• IV Fluids - in cases where the horse is dehydrated, hospitalization with IV fluid administration may be recommended. Electrolyte imbalances seen on bloodwork can be corrected with IV fluids and in some cases, constant administration of lidocaine will be provided through an IV to provide pain relief and increased GI motility. IV fluids are especially useful in treating colics where impaction is the suspected cause. IV fluids (along with oral fluids) will help “hydrate” the impaction, breaking it up and allowing for the horse to pass it.

• Other supportive care - specific diet protocols and other preventative measures such as icing feet for laminitis prevention may be indicated in some cases of colic.

Surgical Management

• If we determine that your horse is potentially a surgical colic, the decision to pursue surgery should be made quickly for the best prognosis. For horses initially seen by Country View Equine Clinic, the decision to pursue colic surgery would result in your horse being transferred to one of the equine surgical facilities in our area for further assessment by a surgeon.

• The decision to send your horse or not send your horse to surgery can be a very difficult one, as it must weigh many factors, including prognosis for successful surgery, prognosis if surgery is not performed, transportation, financial commitment of surgery, and post-operative care. These things must all be considered at a very emotional and stressful time, and unfortunately, time is of the essence. For this reason, it is highly recommended that you consider these things BEFORE the question is every truly posed to you. Things to look into include:

  • If you were to send your horse to surgery, which referral facility would you use?

  • How would you transport them there?

  • What is the cost of surgery? Cost of referral surgery can vary significantly depending on the facility and the surgery that needs to be performed, but at a minimum, the cost for colic surgery in our area ranges from $5,000-$10,000.

    • Payment in full, at time of service is standard practice. However, there are often options like CareCredit or Scratchpay, for third-party payment plans.

  • How will you manage post-operative care when your horse is able to come home from surgery? After surgery, your horse will require a time period of stall rest.

  • Is your answer different for each of your horses? For a variety of very valid reasons, some people may decide that they would perform surgery on some horses that they own, but not on others. This is a completely acceptable conclusion to come to and therefore, these questions should be answered separately for each horse that you own.