Association between the pattern of prophylactic antibiotic use and surgical site infection rate for major surgeries in Korea

Abstract

Objectives : The purpose of this study was to analyze the association between the pattern of prophylactic antibiotic use (PAU) and the surgical site infection (SSI) rate for major surgeries in Korea. Methods : We retrospectively reviewed the medical records of patients who underwent cardiac, colon and gastric surgery, hysterectomies and hip/knee replacements at 20 hospitals, and inclusive of over 500 beds. We randomly sampled 60 cases per surgery type for patients discharged between September and November, 2006. A total fo 2,924 cases were included in our analysis. Cox s proportional hazard analysis was conducted to evaluate the association between the pattern of PAU and SSI rate. Results : The proportion of patients who received their first prophylactic antibiotics (PA) 1 hour before incision was 65.5%, who received inappropriate PAs was 80.8%, and the proportion of patients whose PA was discontinued within 24 hours of surgery was 0.5%. The average duration of PAU after surgery was 9 days. The relative risk (RR) of SSI in patients who received their first PA more than 1 hour before incision was significantly higher than for those who received it within 1 hour prior to incision (RR=8.20, 95% CI=4.81-13.99). Inappropriate PA selection increased SSI rate, albeit with marginal significance (RR=1.97, 95% CI=0.96-4.03). Also, prolonged PAU following surgery had no effect on SSI rate. Conclusions : These results suggest that the pattern of PAU in the surgeries examined was not appropriate. Errors in the timing of PAU and of PA selection increase SSI rate. SSI rate remained unaltered following prolonged PAU after surgery.