A prospective study of postoperative surgical site infections in dogs and cats

OBJECTIVE: To assess postoperative surgical site infection (SSI) rate and to identify associated predictive factors. STUDY DESIGN: Prospective clinical study. ANIMALS: Dogs and cats that had surgery (1010 interventions) during 58 weeks from April 1999 to June 2000. METHODS: Data sheets were completed by clinicians. Patients were controlled for clinical evidence of SSI at suture removal. Two definitions of SSI ("infection" and "infection/inflammation") were developed specifically for this study and used for statistical analysis. Logistic regression models were built in order to identify significant predictive factors for SSI. RESULTS: Wounds with "infection/inflammation" occurred in 5.8% and "infected" wounds in 3% of patients. The outcome "infection" was associated with 3 major risk factors (duration of surgery, increasing number of persons in the operating room, dirty surgical site) and 1 protective factor (antimicrobial prophylaxis). The outcome "infection/inflammation" was associated with 6 significant factors (duration of anesthesia, duration of postoperative intensive care unit stay, wound drainage, increasing patient weight, dirty surgical site, and antimicrobial prophylaxis). CONCLUSIONS: SSI frequency in companion animals is comparable with the frequency observed in human surgical patients. Several significant predictive factors for SSI in small animals surgery were identified. CLINICAL RELEVANCE: Baseline information for SSI surveillance in our hospital and for comparison with other studies was defined. The factors identified may help to predict infections in surgical patients and to take adequate preventive measures for patients at risk.