b'2019 AAEP CONVENTION WRAP-UPprogress with their referring vets.Of the 49 horses in the treatmentAntimicrobial-Impregnated Gauze Helps Wounds Healgroup, four developed incisional infec-tions (8.1%), compared to 13 horses inEquine practitioners commonly encounter traumatic wounds of distal limbs and joints.the untreated group (32.5%)a statisti- Wounds on the distal limbs of horses heal more slowly than wounds on other parts of cally significant difference. With the ap- the body because of a comparatively decreased blood supply, poor soft tissue coverage, plication of medical-grade honey, horsesand an increased incidence of bacterial contamination because of proximity to the ground, in the study were four times less likely toexplained Isabelle Kilcoyne, MVB, Dipl. ACVS, assistant professor in the University of California get an infection. There also appeared to(UC) Davis School of Veterinary Medicine. be no adverse effects at the incision lineWithout appropriate infection control, even small traumatic wounds can be career-limiting in any of the honey-treated horses. or life-threatening. Bacteriological samples were obtainedPolyhexamethylene biguanide (PHMB) is a synthetic compound with a chemical structure from the incision sites of 12 of the 17similar to broad-spectrum antimicrobials. This antibiotic kills bacteria by binding to the bacte-horses with infected incisions. Eleven ofrial cell membrane, causing lysis (disintegration by cell wall or membrane rupture). the 12 suffered from multiresistant infec- Cotton roll gauze impregnated with 0.2% PHMB was developed as a means of reducing tions to common antimicrobials, andbacterial growth within bandaged wounds in humans, said Kilcoyne, who previously con-three of these suffered from methicillin- firmed a 0.2% PHMB-impregnated dressing could help reduce the incidence of colic surgery resistant Staphylococcus aureus (MRSA)incisional infections. In experimental trials conducted by the manufacturer, the PHMB-infections. Notably, all three were mem- impregnated dressing was effective in reducing numbers of penicillin-resistant staphylococ-bers of the control group, meaning theycal species within the bandage and preventing colonization of the organism on human skin did not receive intraoperative medical- beneath the dressing. grade honey. To compare the efficacy of 0.2% PHMB-impregnated gauze and nontreated gauze in reduc-Applying medical-grade honey on theing the growth of bacteria, Kilcoyne, together with Charlene Noll, DVM, and other veterinary linea alba intraoperatively is a simple,specialists at UC Davis, collected and isolated samples of bacteria from wounds, draining tracts, and incisional infections of horses previously examined at the hospital.easy, and rapid procedure that does notThey created petri dishes of those bacterial colonies and placed 0.2% PHMB gauze appear to have any adverse effects, Gus- squares on the colonies for 24 hours. They measured zones of inhibition and compared tafsson concluded. Medical-grade honeytreated and untreated (control) gauze squares. appears to have strong protective factors,We found that the 0.2% PHMB-impregnated gauze squares significantly inhibited the she added, and using it prophylacticallygrowth of staphylococcal species and Escherichia coli species compared with the untreated offers another line of defense againstgauze squares, relayed Kilcoyne.incisional infection in horses undergoingThe PHMB squares inhibited Staphylococcus spp growth by 33-83.1% and E. coli growth colic surgery.Betsy Lynch by 6.5-37%. They saw no inhibitory effect on the growth of Pseudomonas aeruginosa or Enterococcus spp. ARTICLE SPONSORED BY Based on the results of this study, the use of 0.2% PHMB-impregnated gauze reduced the growth of underlying bacteria commonly implicated in orthopedic wounds and infections of horses, Kilcoyne said.Stacey Oke, DVM, MScsoundness prior to sale. However, withare and how best to view them guides the 50 shades of gray these technologiesWerpy in her prepurchase imaging present, which diagnostic images will berecommendations. Other factors that dic- most revealing? tate the images needed include the horses Well, that depends. age, the vets examination findings, and LAMENESS Florida-based radiologist Natashathe buyers previous experiences and aver-Diagnostic Imaging in Western HorseWerpy, DVM, Dipl. ACVR, said prepur- sion to risk.PPEs chase diagnostic imaging in WesternAs imaging technologies advance, Whether someone has a recreational orperformance horses is becoming morepractitioners have learned the limita-professional interest in owning a reining,complex. Horses across all Westerntions of relying on radiographs alone. X cutting, barrel racing, roping, timed- disciplines commonly show wear andrays might not catch certain problems or event, or cow horse, that animal willtear in their feet, hocks, stifles, and knees.might show anomalies that arent useful likely cost a pretty penny. Not surprising,However, each sport tends to manifest itsfor determining clinical relevance then, that diagnostic imaging has becomeown set of problems. especially when the horse is sound. Is it a a central part of Western performanceWatching these horses work andblemish? Will it impact resale? Or could prepurchase evaluations.understanding their athletic expectationsit affect performance over time? Thats Ultrasound, computed tomographyis really important because there arewhen additional imaging techniques (CT), MRI, and nuclear scintigraphy arevery specific predilection sites for injurycould provide a clearer picture of whats finding a place alongside radiography (Xwithin the different disciplines, she said.really going on below the surface. rays) when it comes to assessing a horsesKnowing what those trouble spotsI provide all the options and explain 50March 2020The Horse|TheHorse.comAAEPWrapUp.indd 50 2/5/20 2:54 PM'