Influence of antimicrobial prophylaxis in horses undergoing sutured castrations

To investigate the influence of surgical antimicrobial prophylaxis (SAP) on complication rates and surgical site infections (SSI) in horses undergoing sutured castration in a hospital setting.

Retrospective chart review of a convenience sample.

A total of 220 colts and stallions admitted for sutured castration.

Medical records of sutured castration were assessed for patient characteristics, perioperative and postoperative medications, and postoperative complications within 6 weeks after surgery. The effect of these variables on the occurrence of complications was analyzed using χ² tests, and the association between SAP use and SSI probability was evaluated.

The median age of horses included in the study was 3 years (range 1-14 years), and the overall complication rate was 10.0% (22/220). Surgical antimicrobial prophylaxis was administered to 62% of the patients (136/220). There were no differences in the overall complication rates, with a 7.1% (6/84) complication rate among horses without SAP (SAP-) and an 11.8% (16/136) rate in those receiving SAP (SAP+) (p = .36). There was no association between the use of SAP and the probability of SSI, with an incidence of 3.6% in SAP- and 4.4% in SAP+ (3/84 and 6/136 respectively) (p = 1.0).

Administering SAP did not influence the overall complication rate or the SSI rate following sutured castrations in a hospital setting.

These findings prompt a reconsideration of the use of SAP for sutured castrations under aseptic conditions. The results may also serve as a basis for future randomized controlled trials.