Impact of an Antimicrobial Stewardship Bloodstream Surveillance Program (BSP) in Hospitalized Patients
Bloodstream infections (BSI) in hospitalized patients represent sentinel events characterized by increased mortality. These infections represent an attractive stewardship opportunity because they warrant rapid initiation of empiric antimicrobial therapy, deft transition to directed (gram stain guided) and definitive (susceptibility guided) therapy.
Methods: Under a retrospective pre-post study design, a review of patient charts 18 months before and 18 months after initiation of a hospital BSP was carried out. Pre-intervention, the hospital ward and attending physician were notified of all positive blood cultures (standard of care). Post-intervention an infectious disease pharmacist collaborating with an infectious disease consultant was notified in addition to standard notifications.
Results: 226 patients with BSI were identified pre-intervention and 195 patients post-intervention. The two cohorts were similar in baseline characteristics: the most common source of infection was urinary tract (Figure 1); the most common blood stream isolates were E. coli, S. aureus, beta-hemolytic streptococci and K. pneumoniae (Figure 2); 71.7% of infections were community acquired; 11.4% were polymicrobial. Empiric therapy was given in 82.6% of patients (16.3% non-susceptible). Directed therapy was given in 54.9% of patients (3.5% non-susceptible). The post-intervention cohort received directed therapy on average 4.36 hours earlier (p=.003), were more likely to receive adequate definitive therapy (99.0% post vs 79.1% pre, p<.001), and were stepped down to oral therapy earlier (6 days vs 8 days). Prescription of second generation cephalosporins (0.0% vs 4.3%, p=.05), quinolones (16.7% vs 32.7%, p=.005), clindamycin (2.6% versus 10.3%, p=.03) and aminoglycosides (6.1% vs 14.6%, p=.05) were decreased for directed therapy post-intervention.
Conclusion: A hospital BSP can improve time to first dose of parenteral antimicrobial directed therapy and adequacy of definitive therapy, shorten time from IV to oral step-down and reduce prescription of targeted antimicrobial classes. A BSP can be an effective stewardship strategy in hospitalized patients.
J. Allard, None