Knowing that information, equine veterinarians can compare their own castration track records to a new “gold standard” to see how their results fare, said said Claire Hodgson, BVetMed, CertAVP(EM), MRCVS, a clinical practice veterinarian working in association with the University of Liverpool School of Veterinary Science, in Neston, U.K.
“One of the main purposes of this study was to provide a benchmark for clinicians against which they can audit their individual and practice performances,” she said. “Clinical audit is now routine in human medicine and is becoming commonplace in veterinary medicine as a way to constantly compare performance against a gold standard and strive for the highest performance possible. Hopefully, by providing the baseline standards in general practice, we have made this task easier for clinicians in general practice.”
Hodgson and Gina Pinchbeck, BVSc, CertES, PhD, Dipl. ECVPH, MRCVS, of the University of Liverpool Department of Epidemiology and Population Health, prospectively investigated nearly 500 equine castrations performed by more than 50 veterinarians. The pair collected complication data on the day of each castration and again 30 days post-operatively.
Complications during the procedure occurred in nearly 15% of cases and largely included bleeding and the horse moving around too much, Hodgson said. In the 30 days after surgery, attending veterinarians reported that 11% of horses had complications—mainly swelling, infection, and gait stiffness. She said it’s possible that some “complications” were so minor owners didn’t bother to contact the veterinarian.
“As a procedure that is generally done in the field, in less-than-sterile conditions (compared to a hospital), a degree of swelling and discharge is expected by most involved,” Hodgson said. “But despite this, our general complication rates were very respectable.
“It’s important to remember that ‘complication’ is a broad technical term that covers everything from the animal being a bit quiet and not eating with his usual enthusiasm—which would not be surprising to anyone following a surgical procedure—to the unfortunate situation in which the animal dies,” she added. And, she noted, no horses died in this study.
Because castration procedures have “practically changed very little over the years,” Hodgson said, there’s limited evidence-based medicine methodology (treatment based on well-designed scientific research instead of just experience compiled over the years) to go with it. While that follows the concept of “not fixing what isn’t broken,” in a sense, it doesn’t give a basis for comparison or a starting point for conversations about ways to improve the technique, she said.
“This is part of the reason that there is variation in technique,” Hodgson said. “Some of it is the individual clinicians’ personal preferences because the available current evidence does not suggest that one technique—such as standing sedated castration versus that done in recumbence under general anesthetic—has any significant difference in outcome.”
Their study, while restricted to U.K. practices, should provide a starting point for the development of science-based “best practices” for castration in horses worldwide, she said.
The study, “A prospective multicentre survey of complications associated with equine castration to facilitate clinical audit,” was published in the Equine Veterinary Journal.