Antimicrobial use in critically ill horses.

The study focuses on the issue of antimicrobial use in critically ill horses and the increasing problem of antimicrobial resistance. It evaluates the current practices used in veterinary medicine, highlighting various challenges and suggesting possible adjustments to existing protocols.

Methodology

• The study was conducted using PubMed searches from the period of 1970-present. The researchers searched with specific terms such as “horse,” “foal,” “antimicrobial,” “prophylaxis,” “infection,” “surgery,” “sepsis” and “antimicrobial resistance” to locate relevant articles.

Findings

• The results pointed towards the increasing problem of bacterial antimicrobial resistance which has led to a change in first-line antimicrobial choices, and shortening of duration of prophylactic and therapeutic treatment in horses.
• The veterinary medicine trend appears similar with growing bacterial resistance, but much of it lacks high-level evidence.
• The study outlines medical dilemmas such as cases where the most effective drug is a reserved antimicrobial or distinguishing infectious from noninfectious diseases, and questions around the duration and necessity of prophylactic antimicrobials and their use in primary gastrointestinal disease.
• Important examples noted included purulent infections, neonatal sepsis, colic surgery, and treatment of colitis in horses.

Treatment and Recommendations

• The study indicates that enrofloxacin, cephalosporins, and doxycycline reach therapeutic concentrations within the lungs of healthy horses but should not be used as first-line treatment due to their reserved status.
• For neonatal foals at high risk of bacterial sepsis, antimicrobial treatment remains essential but the length of treatment should perhaps be reduced.
• One study suggested no difference between 3 and 5 days of perioperative antimicrobial treatment in colic surgery but shorter durations were not evaluated.
• No high-level evidence exists to recommend antimicrobial treatment of adult horses with undifferentiated diarrhea.

Conclusions

• The study concludes there are few conclusive, evidence-based recommendations but commonly used antimicrobial combinations remain vital for treating purulent infections.
• Antimicrobial treatment for compromised foals should be halted after recovery.
• Prophylactic antimicrobials are likely not necessary beyond three days after colic surgery and perhaps even shorter durations could be equally effective. Antimicrobial prophylaxis in adult horses with diarrhea is considered unlikely to be beneficial.