Whenever it's possible to perform a procedure with the horse standing and sedated, it's better to do that than to use general anesthesia, said Brian Gilger, DVM, MS, Dipl. ACVO, founder of the Equine Ophthalmologic Service at North Carolina State University. His presentation at the 2002 American Association of Equine Practitioners Convention was "How to Prepare for Ocular Surgery in the Standing Horse."

"Horses with orthopedic or other medical problems might be at higher risk for anesthesia complications and should not undergo routine general anesthesia (i.e., general anesthesia for the purpose of a non-emergency procedure)," he began. "Even healthy horses can injure themselves on recovery from general anesthesia and are predisposed to develop colic, cecal impactions, and myositis (inflammation of voluntary muscle) in the post-anesthetic period. Standing procedures require less hospitalization (time), less technical support, less cost and time, and decreased need for surgical and anesthetic equipment and facilities–and thus decreased cost to the horse owner.

"However, there are challenges with standing ocular (eye) surgery–you generally need magnification, and thus the horse must be perfectly still," he continued. "Many (eye) procedures thus require general anesthesia. But with appropriate tranquilization, ocular nerve blocks, and restraint, many ocular surgeries can be performed adequately in standing horses