Your Guide to Colic Surgery in the Horse

By: Dr. Lydia Gray

If your horse needed emergency colic surgery to save his life, would you have all the information needed to make a decision quickly? In this article, we take you through the process from beginning to end, explaining the difference between a “medical” colic and a “surgical” colic and how veterinarians tell the difference, sharing survival rates and complications, the average cost of colic surgery, and the typical recovery time, and, most importantly, helping you understand your role in all of this and how you can make the best decisions for your horse.

The latest estimates are that 5 to 10% of the US horse population colics each year, with the vast majority (90 to 95%) being mild cases that resolve with simple medical management and treatment on the farm. However, that still leaves approximately 5 to 10% of colicky horses needing to be referred to a surgical facility and possibly undergoing surgery to correct the issue. Why do some horses get better with the standard pain-killers, sedatives, fluids, laxatives, and lubricants (ie medical treatment) and others don’t?

Medical vs Surgical Colic

Not all colics are created equal, as there’s a lot that can and does go wrong in the abdomen of the horse. By remembering that the term “colic” simply refers to abdominal pain and not to a specific section of bowel or to a certain problem, then it makes sense that a horse showing signs of belly pain could have:

• ulcers in the stomach (a medical colic), or
• a strangulating obstruction in the small intestine (a surgical colic), or
• an impaction in the large colon (a medical OR surgical colic), or some other problem

How does your vet know when a colic is medical and can be treated conservatively at home vs when a colic is surgical and must be referred to a facility that can perform emergency abdominal surgery? Once your vet arrives at the farm, everything he or she does – ask questions about the recent history, perform an examination that may include nasogastric (nose-to-stomach) intubation and rectal palpation, begin treatment – provides clues as to the nature of this episode.

For example, if your horse’s medical history includes colic surgery a year ago, then there’s a possibility he has “adhesions,” a complication of a previous abdominal surgery where sections of bowel can stick to other sections of bowel, the body wall, or other organs, and may require a second surgery to correct. Example number 2: during the exam, if a large amount of gas, liquid, or feed “reflux” comes up out of the tube in your horse’s stomach, then this could indicate a blockage in the bowel that may require surgery to correct (rectal palpation is also used to detect blockages including impactions, displacements, and twists). A third example is if your vet gives your horse medication for pain as part of treatment but the pain persists or immediately returns. This could also indicate that surgery is necessary.

On the other hand, if the history includes recent turnout onto lush spring grass, then your vet will be leaning towards a simple gas colic as a diagnosis. If the heart rate is low (in the normal range of 28 to 42 beats per minute) and the gums are moist and pink during the examination, your horse’s cardiovascular status is good and his pain levels are likely low. And if one dose of a pain-killer has him asking for food, passing manure, and looking to play with his buddies, chances are that the episode has passed.

Your vet may suggest immediate referral to an equine hospital for further workup, additional medical support, or emergency abdominal surgery if:

1. if there are signs of complete or partial obstruction of the bowel
2. if there is persistent or severe abdominal pain
3. if your horse appears to be going into circulatory shock – or
4. if there is a lack of response to medical treatment in general

Colic Surgery Survival Rates and Post-Op Performance 

Over the last 20 years or so, great strides have been made in colic surgery technique and general anesthesia safety, with a much higher percentage of horses surviving and thriving after the procedure than ever before. According to data from Practical Guide to Equine Colic edited by Louise Southwood and published in 2013, current survival rates for colic surgery range from 80 to 95%. This number varies with the type of lesion – where it is, what it is, and how it was fixed– as well as the hospital/surgeon and even the part of the country. However, the greatest factor in determining whether a horse undergoing colic surgery lives or dies is early recognition by the owner and early referral by the veterinarian to a full service equine hospital with intensive care and surgery facilities.

While many horse owners believe that older horses should not or cannot undergo colic surgery, those without health issues actually tolerate it quite well. In a 2014 presentation at the American Association of Equine Practitioners (AAEP) Annual Convention, Dr. David Freeman shared that horses older than 16 years – even those in their late 20s to early 30s –handled general anesthesia and colic surgery well, and their postoperative survival rates were comparable to those of younger horses.

Dr. Freeman also reported that most horses return to their previous level of performance after colic surgery, even when this means at the highest levels of activity and competition such as racing, eventing, or Grand Prix dressage or show jumping. Knowing that survival rates are high, even for older horses, and that it’s very likely a horse undergoing colic surgery will bounce back well enough to take up where he left off in his performance career, it’s time to consider other factors involved in the decision whether or not to consent to colic surgery, such as the cost.

The Cost of Colic Surgery

The type of colic, the severity of the condition, where in the country you’re located, and other factors all weigh in to the final cost of colic surgery. In her book, Dr. Southwood writes that surgical management, including emergency admission plus basic postoperative care, at U.S. hospitals in 2012 ranged from $5,000 to $10,000. She notes that in most cases, facilities will ask for a deposit of 50% of the estimate at the time of admission. Claims filed through SmartPak’s ColiCare™ Program into 2016 indicate that the average cost of colic surgery nationwide, including pre-op and post-op care, is $7,800.

Whether your horse is enrolled in a colic surgery reimbursement program like ColiCare or has insurance coverage that extends to colic surgery, owners and anyone with care, custody and control of a horse must be familiar with the terms and conditions of these programs and policies. Things to ask yourself before being faced with a life-threatening decision to make include:

• Do I have to get prior approval from the company before agreeing to colic surgery?
• Does the company pay the vet or hospital directly or do I pay the bill and get reimbursed?
• Is there a deductible or co-pay and if so, how much is it?
• What things might void the agreement such as not disclosing previous colics?
• How do I submit a claim?
• When do I submit a claim? (that is, must I turn in paperwork and bills by a certain date?)
• What is the maximum payout and is there a limit per event or per year?

Not being able to say “yes” when the vet asks if surgery is an option is a terrible feeling, especially when your horse is enrolled in a reimbursement program or has an insurance policy. Save time and anxiety later by reading the fine print now and complying with all requirements.

The Surgical Procedure and Complications

If you did decide to transport your horse to a surgical facility, expect things to happen fairly quickly once you arrive, unload, and check-in. Also expect some of the same exams, such as nasogastric intubation and rectal palpation, to be performed again, as a change in your horse’s status helps the new vets determine if your horse is getting better or getting worse, in which case he may be rushed to surgery.

For horses that seem unchanged upon arrival and fairly stable, the hospital may perform additional diagnostic tests to try and figure out what the cause of his pain and discomfort is, such as bloodwork, abdominocentesis aka “belly tap,” and abdominal radiography (X-rays) or ultrasound. An intravenous catheter may be placed in one or both jugular veins in order to administer IV fluids as well as to be able to administer sedatives, pain-killers, and anesthesia-inducing agents, if surgery becomes necessary.

Surgery is a tool for both treatment AND diagnosis, so horses in which a specific lesion has not been identified may be taken to surgery in an attempt to figure out why he is not responding to medical treatment. Once the horse is placed under general anesthesia, some hospitals have a viewing window into the surgical suite and allow owners to watch the procedure. You may see “booties” on his hooves or covering his shoes, an endotracheal (breathing) tube in his mouth, EKG wires and blood pressure monitors, and a clipped and scrubbed abdomen or one that’s already draped.

The surgery itself involves an incision into the ventral (underside) abdomen, usually made along the line between the navel and sheath/udder. Each surgeon then has his or her own systematic method of exploring the abdomen and intestine so that no lesion is overlooked or section missed. Corrections are made as necessary, such as removing impactions, decompressing gas, untwisting bowel, returning a section to its proper location, resecting (removing) a section of bowel or other. Then the body wall is closed in several layers and the horse is moved to a special, padded recovery room to carefully wake from anesthesia, after which he is walked to a stall. Depending on how long it takes to find and correct the lesion, colic surgery can range from one to four hours.

The most common complication of colic surgery is another episode of colic, which occurs in 25 to 35% of all horses that have undergone colic surgery. Other complications include adhesions,  ileus (the absence of peristalsis, the normal wave-like movement of the intestine which propels food forward), problems with the incision area or where the IV catheter was placed, peritonitis or inflammation of the peritoneum (the abdominal cavity), laminitis, diarrhea, and pneumonia. Some complications occur immediately, while the horse is still recovering in the hospital (typically between 5 to 10 days), and some occur once your horse is back home, most often within the first two or three months following surgery. Someone from the surgical team will sit down with you and review discharge instructions as well as send you home with a copy and make sure your regular vet also gets a copy. Those instructions tell you not only how to care for your horse but also what to monitor and who to call if you have any questions or something doesn’t seem quite right.

Colic Surgery Recovery and Aftercare

Discharge instructions usually address general monitoring, caring for the incision, feeding, exercise, and medication, if any. General monitoring includes observing your horse for EDUD or Eating, Drinking, Urinating, and Defecating, as well as making sure he’s BAR (bright, alert, responsive), that he’s regaining any weight he may have lost during this episode, and that he’s not showing any signs of colic. The incision should be inspected daily for signs of infection such as discharge, redness, or excess swelling, as well as “dehiscence,” in which the sutured edges split apart or gape open.

The surgical facility will have introduced your horse gradually to his regular diet, feeding small meals frequently, and will give you clear instructions on what and how much to give at what intervals as you continue to restore him to full feed. Depending on what was found during surgery and what the original cause of the colic was determined to be, your horse may or may not return to his regular diet. For example, if an ileal impaction was discovered and his diet had been coastal Bermuda hay, the veterinarians may suggest he be switched to another type of hay that has less of a tendency to cause an obstruction.

A typical timeline for exercise begins with four weeks of stall rest, during which time your horse can be handwalked and handgrazed. This is followed by another four weeks of turnout, alone, in a stall with a small run or paddock attached. At the end of this 60-day or two-month period, if all is still going well, most horses can be given full turnout with other horses. Light longeing and riding is usually permitted at this time, with a gradual return to full training at the 90 day mark.

By answering some of the most common questions surrounding colic surgery – when a horse needs surgery vs medical care, which factors go into making the decision for an individual horse, and what to expect during and after – hopefully some of the “mystery” will be taken out of this procedure leading to improved outcomes for both horses and horse owners.

SmartPak strongly encourages you to consult your veterinarian regarding specific questions about your horse's health. This information is not intended to diagnose or treat any disease, and is purely educational.