Methods: This is a retrospective, non-inferiority, cohort study comparing outcomes of patients who received cefazolin plus metronidazole versus cefoxitin for perioperative elective CRS prophylaxis. The study was approved by the network Institutional Review Board at Seton Healthcare Family. Patients at least 18 years of age who received at least one dose of antimicrobial prophylaxis with cefazolin plus metronidazole or cefoxitin for elective colorectal surgery were included. Exclusion criteria are emergency colorectal surgery, revision of previous colorectal surgery, bacterial infection at the time of procedure, perforation during surgery, antimicrobial therapy within one week prior to procedure, patients greater than 89 years of age and pregnancy. The primary outcome is the incidence of surgical site infections within 30 days after surgery. A one-sided test for non-inferiority with a multivariable regression analysis was used for the primary outcome. Secondary outcomes include incidence of Clostridium difficile infection and incidence of secondary bloodstream infection.
Results: After 400 colorectal procedures, 36 patients (9%) developed SSIs. Twelve SSIs (6%) occurred in the cefazolin plus metronidazole group compared to 24 (12%) in the cefoxitin group. There were no cases of C. difficile or secondary bloodstream infections in the study cohort.
Conclusion: Fewer patients in the cefazolin plus metronidazole group developed SSIs within 30 days of CRS than in the cefoxitin group. These results support the use of cefazolin plus metronidazole for prevention of SSIs in CRS.
D. Rose, None
T. Knight, None