Non-observance of guidelines for surgical antimicrobial prophylaxis and surgical-site infections

Objective: a prospective multicentre study was conducted to assess major aspects of surgical prophylaxis and to determine whether inappropriate antimicrobial prophylaxis was a factor associated (risk or protective factor) with surgical site infection (SSI). Method: surgical prophylaxis practices were assessed by analysing four variables: indication, antimicrobial agent, timing and duration. Univariate and multivariate analyses were carried out to identify predictors of SSI among patient-specific, operation-specific and antimicrobial prophylaxis-specific factors. Results: The frequency of SSI was 2.7% (13 SSI in 474 observations). Total compliance of the prescription with guidelines was observed in 41.1% of cases (195 prescriptions). Of the 139 patients who received an inappropriate drug, 126 (90.6%) received a drug with a broader spectrum than the recommended drug. Prophylaxis was prolonged in 71 (87.7%) of the 81 patients who received prophylaxis for inappropriate lengths of time and 43 (61.4%) of the 70 patients who did not receive prophylaxis at the optimal moment were treated too late. Multivariate analysis clearly demonstrated that SSI was associated with multiple procedures (relative risk 8.5), short duration of prophylaxis (relative risk 12.7) and long-term therapy with antimicrobial agents during the previous year (relative risk 8.8). Conclusions: the ecological risk of the emergence of resistance associated with the frequent use of broad-spectrum antibiotics and prophylaxis for longer periods was not offset by individual benefit to the patients who received inappropriate prophylaxis.