Surgical antibiotic prophylaxis – The evidence and understanding its impact on consensus guidelines

Background: Surgical site infections are complications of surgical care that may be prevented with appropriate surgical antibiotic prophylaxis (SAP). SAP is the most common indication for antimicrobial use in Australian hospitals; however, it is associated with high rates of inappropriate use. Inappropriate SAP is associated with adverse consequences for both the patient and the community. The underlying reasons for inappropriate use, however, are not well delineated. Potential factors include the quality of the evidence base regarding SAP use and available guidelines. Methods: The literature review focused on research classified as having Level 1 evidence according to the National Health and Medical Research Council (NHMRC) evidence hierarchy. Findings were then compared to the current Australian recommended guidelines (Therapeutic Guideline: Antibiotic Surgical Prophylaxis). Results: Overall, 50 systematic reviews (SR) and meta-analysis (MAs) were identified for the review. The evidence examined highlights that first-generation cephalosporins are the antimicrobial agents of choice and single-dose prophylaxis is effective for the majority of surgical procedures included in this review. There is limited evidence pertaining to a specific optimal antimicrobial, dosing and timing. Thus, there is no overarching Level 1 evidence combining all elements for an optimal SAP regimen (i.e., choice of agent, dose, route and duration) to support individual Therapeutic Guideline: Antibiotic recommendations, although there may be Level 1 evidence for the individual elements. Conclusions: Considerable evidence supports the use of SAP; however, there are gaps in the evidence behind recommendations for the most appropriate SAP regimen for different surgical procedures. Expert consensus guideline development aims to narrow these gaps, but guideline implementability and uptake are influenced by multiple factors including the comprehensiveness of the evidence. Further research is warranted to examine guideline implementability and uptake, and to identify problematic areas surrounding surgical prophylaxis prescribing.