About 25% of the horses colic each year, making it a common equine emergency.  While most cases do not require surgery, about 10% of them do involve lesions that are only correctable through surgery. But how does a veterinarian decide whether to put a horse under the knife? Diana M. Hassel, DVM, PhD, Dipl. ACVS, ACVECC, an associate professor of equine emergency surgery and critical care at the Colorado State University College of Veterinary Medicine and Biomedical Sciences, and colleagues recently reviewed methods veterinarians can use to evaluate whether a colicking horse should be referred for surgery. “It is essential that the veterinarian is aware that an owner is willing to send their horse to a referral facility if needed right from the start,” Hassel said. “That way, if there are any concerns about the possibility of the horse needing surgery, there will not be delays in transport that could negatively affect prognosis.” Next, Hassel and colleagues recommend veterinarians perform a thorough physical examination, including rectal palpation and passage of a nasogastric tube, to obtain valuable information that will help them determine if referral is needed. Veterinarians can also use transabdominal ultrasonography, abdominocentesis (sampling of abdominal fluid), lactate analysis of peripheral blood (blood in the extremities) and/or abdominal fluid, and blood glucose concentration as diagnosis tools to guide a recommendation for surgical referral. “Although most of the factors described are known, many still remain rarely used in practice,” Hassel noted. “The value of abdominal ultrasound in early diagnosis of several GI disorders is extremely high, yet many practitioners do not routinely use it.” So what is Hassel's advice to an owner of a colicky horse? “My advice to owners who find their horse acting colicky is to immediately call their veterinarian and describe the symptoms their horse is showing,” she said, because in cases that require surgery, early detection and referral are key to a successful recovery.