Colic is the term often used to describe abdominal pain in the horse. A colic not responding to analgesics (pain relief) would be our main reason for performing abdominal surgery (exploratory laparotomy).
The majority of the surgical cases at Bourton Vale are horses belonging to our clients, but many are referrals from other practices in the area.
The cause of abdominal pain almost always originates in the gut, and there are multiple reasons for gut pain ranging from simple gaseous distension to conditions that require resection of devitalised intestine. Differentiating between medical and surgical cases can be difficult, especially in youngstock. An early and accurate diagnosis by the vet with the appropriate treatment is paramount for cure and survival.
Diagnosis of colic often relies mostly on careful observation of the horse including assessing the heart rate, mucous membranes and hydration. More often than not, a rectal examination will be carried out to feel for internal distension and a stomach tube will be passed to search for gastric reflux or to administer an electrolyte solution. Occasionally ultrasound of the abdomen will be carried out to further assess the intestinal tract. A belly tap will be sometimes taken to assess the white cell count and the peritoneal fluid in the abdomen, along with a blood sample to assess hydration. By assessing the patient thoroughly, and carefully observing behaviour displayed once analgesics are administered, we can usually determine whether the horse requires surgical treatment.
It is imperative that the vet examines the horse in its initial state and no drugs are administered prior to the vets arrival. In most cases horses are treated with analgesics and anti-spasmodic drugs, which in some cases can resolve the issue.
By no means is the surgical option to cure colic an easy procedure. General anaesthesia comes with its own risks, and requires a full team to monitor the patient and assist with the induction and recovery process. Almost all cases of abdomen surgery are entered via an incision on the ventral midline. Surgery can take from 2 to 5 hours depending on the problem that is encountered once the surgery begins. All patients are given fluids, anti-biotics, anti-inflammatories and intestinal stimulants. The veterinary surgeon will have a good idea of outcome when the problem is found, and whether the continuation of surgery is viable. Common problems may be encountered including classical twists, intussusceptions, displacements or physical obstruction. In most cases, correction can be achieved. In cases where the intestine has lost function due to grass sickness, it is usually fatal and cannot be corrected.
Once surgery has been completed and the horse has recovered, the lengthy process of intensive aftercare begins. This requires re-introducing food and encouraging motility by exercise, gastric emptying (via stomach tube) and medication. Post operative blood samples are taken to carefully monitor recovery.
Bourton Vale carry out approximately 50 emergency abdominal surgeries under general anaesthesia per year, and we are pleased to report that more than 80% of patients return home in full health. In the majority of cases, the on call veterinary team receive patients during the night and it is all hands on deck to ensure the horse has the best chance of survival by acting quickly and efficiently.
Other reasons for abdominal surgery include emergency caesareans, castration, elected exploratory surgery, hernia repair and biopsy.