Colic FAQ
The Sefton Equine Hospital

1. What percentage of colic cases require surgery?
In a survey of cases seen in general equine practice, over the course of two years (Proudman 1991), it was established that the vast majority of cases (93%) are medical and can be treated with appropriate supportive medicines such as painkillers. Only 7% of horses and ponies had problems which could only be treated by surgery.

2. What causes the types of colic which do not need surgery?
The most common cause of colic in the horse (up to 72% of cases) is so-called spasmodic colic. This is when the intestines, for some reason, become over-active, and the spasms of the muscle walls of the intestines are painful.

The next most common cause is impaction of the large intestines. This accounts for up to 15% of cases. Many of these cases are successfully treated with liquid paraffin (or a similar agent) by stomach tube, to break up the impaction and lubricate the intestine, together with painkillers. However, in difficult impactions, it may take several days for a blockage to be completely cleared.

3. What causes the types of colic which do need surgery?
The general problem in a horse with colic which requires surgery is that a piece of intestine gets itself into an abnormal position in which it becomes wedged. The intestine can be twisted in a way which means it cannot untwist, it can go through a "hole", either in the body wall (an external hernia) or inside the body (an internal hernia), or something can wrap itself around the intestine. A common cause of the wrap-around type of colic in older ponies is a pedunculated lipoma. This is a fatty deposit growing on a stalk from the membrane which supports the intestines. A lipoma can swing round a piece of intestine in such a way that its stalk blocks the intestine and cuts off its blood supply.

4. What is involved in surgery for colic?
If the decision is taken to operate on a horse or pony, it is given a general anaesthetic and placed on its back on an operating table. A hole about a foot (30 cm) long is made into the abdominal cavity and the intestines are explored to find the site of the blockage. If the problem can be cleared easily and the intestine still has its blood supply, that may be all that is required. However, usually it is necessary to remove a section of dead intestine and stitch the two remaining ends together. In some horses, it is not possible to reconnect the pieces of intestine, while, in others, so much of the intestine is damaged that they could not live if everything which had to be was removed. Unfortunately, these cases have to be put down under the anaesthetic. Where the intestine can be repaired, the surgical wound in the abdomen is repaired, and the horse recovered.

5. What are the chances of success?
This can be considered in two parts: (a) cases which leave the hospital, and (b) cases which have a subsequent problem at home.

(a) The overall chances of saving a horse’s life with colic surgery, and it leaving the hospital, are about 50%. However, this figure conceals certain types of very serious colic which can only be treated successfully if the horse is operated on within 3-4 hours after the problem starts. A twist of the large intestine which may be seen within 2 weeks of a mare having a foal is like this. Once more than 4 hours have elapsed, the large intestine rapidly goes beyond the stage at which it can be saved and horses usually have to be put down.

Even if a horse recovers from the initial surgery, there is still one major problem which may prevent the colic getting better and the horse going home. This is known as ileus. Ileus is the name given to lack of movement of the intestines. In a proportion of cases, due to low grade damage to the intestines left in the horse, the intestines never regain their normal ability to propel food along their length. This means that the horse is left with a functional (as opposed to a physical) blockage. Unfortunately, such horses have to be put down.

(b) The 50% of horses which survive will not all have an event-free convalescence. Many will develop adhesions where pieces of intestine stick to each other, other organs in the abdomen, such as the spleen, or to the wall of the abdomen. This can lead to transient impactions and recurrent bouts of medical colic, or, in the worst cases, to twists of intestine around the stalk-like adhesion and another colic problem requiring surgery. Over the course of several months/years, up to half of colic cases which survive are likely to have mild or severe complications, and a proportion will have to be put down.

6. Is the colic my fault?
If you regularly worm your horse, including using a wormer which will get rid of tapeworms, the answer, almost certainly, is no! Worms are associated with an increase in certain types of colic, including spasmodic colic and some impactions. Tapeworms, in particular, have been associated with thickening of the junction between the small and the large intestines, leading to blockages which can require surgery.

7. What does colic surgery cost?
Each case is different, so no two bills are alike. However, the range, in 2000, would be £2,000-£5,000, with £3,000 being the average. £2,000 would cover a straightforward surgery, where the problem is quickly corrected, the horse needs very few drugs after surgery, and goes home after about a week. Horses which are very sick at the time of surgery, require a greater range of drugs during the operation, and in the immediate post-operative period, and incur correspondingly higher bills. In addition, horses which develop ileus require much more nursing care and many more litres of intravenous fluids if they are to have a chance of surviving.

8. Does my horse’s insurance cover the treatment?
If you are insured for veterinary fees, this would normally cover colic surgery up to the limit set for each incident. Always read the small print carefully. Some policies purport to offer thousands of pounds of cover but the maximum for a single problem may only be a few hundred pounds. Insurance for an incident costing up to £3,000 will cover the bulk of the fees in most cases of colic, but, in 2000, £2,000 is really too little cover. Most insurance companies do not cover livery while the horse is staying at a hospital, and there is usually an "excess" on the policy which means that you are liable for the first £50-£100 of the bill.

9. What should I do when my horse comes home after surgery?
You will be given specific instructions, when your horse returns home, on the appropriate management. This will involve a period of 2-4 months in a stable, followed by a gradual return to work. The length of any lay-off period is determined by a number of factors, such as how ill your horse was with the colic, the size of the surgical wound, and how well the wound is healing.