Colic Surgery and Return to Activity in Horses

The word “colic” can inspire fear and dread among horse owners. Although colic occurs in many horses at some point during their lifetime, it is often a brief episode that resolves uneventfully. Some horses may develop acute colic, however, which requires surgery and, ultimately, euthanization due to the severity of the lesion or complications after surgery. Yet, there is hope for horses after colic surgery (ventral midline celiotomy). In a recent study of horses that underwent colic surgery, the majority of animals survived to discharge, recovered fully, and returned to their prior level of activity.

In this retrospective study, recently published in Acta Veterinaria Scandinavica, researchers evaluated 236 horses that underwent colic surgery at the Helsinki University Equine Teaching Hospital in Finland between 2006 and 2012. The objective of the study was to evaluate the short- and long-term effects of celiotomy on a heterogeneous population of horses, including survival more than 8 years after surgery, postoperative complications, return to athletic function, and owner satisfaction. The equine patients were followed either until they died or until the end of the study on November 30, 2014, with a total time of following these patients at 8 years 10 months. Of the study horses, 17.4% were euthanized during surgery and 20.8% were euthanized during hospitalization after surgery; 82.6% recovered from anesthesia.

Of the 195 horses that survived surgery, 146 (74.9%) survived to discharge. The authors reported that the most common diagnoses at surgery were nonstrangulating displacement of the large intestine (37.3%), strangulation of the small intestine (22%), and strangulating displacement of the large intestine (20.3%). Enterotomy was performed in 50.4% of cases during surgery. Complications included postsurgical reflux in 27.2%of horses, and a second laparotomy was performed in 7.2% (14/195) of the operated patients (11 during the immediate postoperative period and 3 after discharge). Of the 135 horses for which full follow-up data were obtained, surgical site infection (ie, incisional drainage) occurred in 28.9% and 11% developed an incisional hernia.

If the horse survived to discharge, the prognosis for long-term survival and return to previous level of activity was good. Median survival time was 79.2 months; 83.7% of horses were able to return to their previous or intended activity after surgery, and 78.5% performed at or above their previous level of

performance. While colic recurred in 20% of cases within the first year after surgery, horses with large intestinal lesions were 3.3 times more likely to have another episode of colic than were horses with small intestinal lesions.

The mean age of the horses at the time of surgery was 8.9 years, with a range of 4 days to 22.2 years. Interestingly, the age of the horse did not affect overall survival in this study. Older horses (≥15 years) had no significant difference in survival rates compared with younger horses (0—14 years); however, the number of older horses in this study was small (16%). Various breeds were represented, including Warmblood, Standardbred, Finnhorse, and other horse breeds; however, Warmblood horses were the most prominent breed (38.6%) in the study. Mares, stallions, geldings, and ponies were included.

The majority of owners (96.3%) were satisfied with the veterinary care that their horses received, and 98.5% stated that their horse’s recovery was satisfactory to good. Of the 146 horses that were discharged, survival information (the date and reason of death) was obtained for 143 (97.9%). A total

of 135 owners were interviewed either by phone or email questionnaire.

The study authors stated that after colic surgery, the “majority of discharged horses had a good prognosis for long-term survival, [and] were able to return to their intended use, compete postoperatively on a satisfactory level, and also perform for several years after the operation.”

Dr. Amy Bentz is a 1997 graduate of the University of Pennsylvania School of Veterinary Medicine. She is co-founder of Academic Veterinary Solutions, serves as equine chair for the Pennsylvania Veterinary Medical Association's Scientific Program Committee, teaches at University of Pennsylvania and Manor College, and is a consultant for Veterinary Information Network.