Clinical and economic outcomes of a prospective antimicrobial stewardship program

Purpose A pre–post analysis of an antimicrobial stewardship program (ASP) involving the use of data-mining software to prospectively identify cases for ASP intervention was conducted. Methods The investigators evaluated clinical outcomes and cost metrics before and after implementation of the ASP, which entailed daily physician review of summary reports on all adult inpatients receiving antimicrobial therapy. The primary outcome measures were annual antimicrobial expenditures and rates of infections due to common nosocomial pathogens; secondary outcome measures included patient survival and length of stay (LOS) in cases involving the indicator diagnoses of pneumonia and abdominal sepsis. Results Antimicrobial expenditures, which had increased by an average of 14.4% annually in the years preceding ASP implementation, decreased by 9.75% in the first year of the program and remained relatively stable in subsequent years, with overall cumulative cost savings estimated at $1.7 million. Rates of nosocomial infections involving Clostridium difficile , methicillin-resistant Staphylococcus aureus, and vancomycin-resistant enterococci all decreased after ASP implementation. A pre–post comparison of survival and LOS in patients with pneumonia ( n = 2186) or abdominal sepsis ( n = 225) showed no significant differences in those outcomes in either patient group, possibly due to the hospital’s initiation of other, concurrent infection-control programs during the study period. Conclusion A prospective collaborative ASP employed automated reports to efficiently identify key data for ASP review. After ASP implementation, antimicrobial expenditures and rates of nosocomial infections caused by resistant pathogens dropped without significant changes in patient survival, LOS, and readmissions for the two studied illness categories.