Impact of perioperative prophylactic antibiotics on surgical site infection rate after skin tumor removals in dogs: a prospective observational study.

Abstract

To identify the overall surgical site infection (SSI) rate after skin tumor resections and to explore the association between various factors on SSI development with a particular interest in perioperative prophylactic antibiotics (PPA) and infection rates of mast cell tumor (MCT) removal.Dogs that underwent skin tumor removal were prospectively enrolled in active SSI surveillance (30 days) between 2020 and 2022. Collected data included: tumor type, ASA (American Society of Anesthesiologists) score, surgery and anesthesia time, PPA usage, hypothermia and hypotension status, and duration of hospitalization. Descriptive statistics and logistic regression were used to explore the association between the above factors and SSI development.One hundred and four out of 174 eligible dogs were included. The SSI rate in the studied population was 9.6% (95% CI 5 to 17, 10/104). The rate of SSI after mast cell tumor (MCT) removal was 11.5% (95% CI 4 to 23, 6/52) and in other skin tumors it was 7.7% (95% CI 2 to 19, 4/52). PPA was administered in 23.1% of cases (95% CI 4 to 19, 24/104). SSI occurred in 10.0% (95% CI 4 to 19, 8/80) of dogs without PPA and in 8.3% (95% CI 1 to 27, 2/24) of dogs with PPA. Logistic regression showed no significant association between PPA use or tumor type and SSI occurrence. Neither PPA nor MCT had a significant impact on SSI.In the study population skin tumor resections had an increased SSI risk compared to the expected 4-5% reported in clean procedures in literature. Additionally, MCT resections seem to exhibit a higher SSI rate than resections of other skin tumors. PPA usage showed no protective effect which is in line with the current recommendations to not give PPA.