Current Antimicrobial Use in Horses Undergoing Exploratory Celiotomy: A Survey of Board-Certified Equine Specialists

SIMPLE SUMMARY: Recommendations for antimicrobial prophylaxis are well described for abdominal surgery in human medicine, but the information is limited for equine veterinary practice. In addition, recent studies support a reduced duration of antimicrobials postoperatively in horses undergoing celiotomy compared to what has been previously reported; however, protocols vary widely between practices. The overall objective of this study was to provide an updated characterization of the ‘current state of play’ of antimicrobial use in horses undergoing emergency colic surgery and the perceived risk of postoperative complications. Specifically, the aim was to poll veterinary internists and surgeons to determine current usage among respondents in the United States. Improved knowledge of recommendations for antimicrobial prophylaxis for commonly performed procedures in equine practice, such as abdominal surgery, may help to reduce postoperative complications and enhance antimicrobial stewardship at a time when resistance is increasing in equine practice. ABSTRACT: In the past decade, there has been a considerable increase in the recognition of antimicrobial resistance in equine practice. The objective of this study was to survey the current clinical use of antimicrobials for a commonly performed surgical procedure (exploratory celiotomy) with the goal of understanding how recent literature and changes in microbial resistance patterns may have impacted antimicrobial selection practices. An electronic survey was distributed to veterinary professionals within the American College of Veterinary Internal Medicine (ACVIM) and the American College of Veterinary Surgery (ACVS). A total of 113 completed surveys were returned. Practitioners reported antimicrobials were most frequently given 30–60 min preoperatively (63.1%). Two antimicrobial classes were typically administered (95.5%), with gentamicin (98.2%) and potassium penicillin (74.3%) being the most common. Antimicrobials were typically not re-dosed intraoperatively (78.6%). Factors that affected overall treatment length postoperatively included resection (81.4%), bloodwork (75.2%), enterotomy (74.3%), fever (85.0%), incisional complications (76.1%), and thrombophlebitis (67.3%). The most common duration of antimicrobial use was 1–3 d for non-strangulating lesions (54.4% of cases) and inflammatory conditions such as enteritis or peritonitis (50.4%), and 3–5 d for strangulating lesions (63.7%). Peri-incisional and intra-abdominal antimicrobials were used by 24.8% and 11.5% of respondents, respectively. In summary, antimicrobial usage patterns were highly variable among practitioners and, at times, not concordant with current literature.