Effects of a Staphylococcus aureus Bacteremia Care Package Intervention on Patient Care in a Community Teaching Hospital: A Propensity-Score Matched Comparison

Background: Staphylococcus aureus bacteremia (SAB) is an important cause of morbidity and mortality. Suboptimal treatment has been associated with poor patient outcomes. Our antimicrobial stewardship team evaluated SAB management based on predefined performance measures both prior to and after instituting a “care package” intervention led by clinical pharmacists and infectious diseases physicians. The primary outcome was time from finalized blood culture to appropriate, targeted antibiotics. Secondary outcomes included a 4-point “optimal care score” (OCS) consisting of targeted antibiotic therapy within 24 hours, repeating blood cultures, antibiotic duration assessment, and appropriate duration of therapy, as well as presence of ID consult, and a combination of infection relapse and mortality.

Methods: This was a quasi-experimental, propensity score matched study of SAB management. Patients were retrospectively evaluated from October 2011 – October 2012, and intervention took place from November 2013 – December 2015. Intervention consisted of a clinical pharmacist contacting the primary team after identification of S. aureus in the bloodstream to recommend 1) appropriate antibiotics within 24 hours, 2) repeat blood cultures to document clearance, 3) assessment to determine appropriate duration of antibiotics, 4) and appropriate duration of therapy. These constituted a 4-point OCS. ID consult was also recommended. Patients were propensity score matched 1:1 based on age, diabetes, presence of hardware, methicillin-resistant S. aureus (MRSA) isolate, and stratified infectious source. Patients > 18 with SAB were included.

Results:

	Pre (N = 83)	Post (N = 83)	p-value
Hrs to app. abx (avg. + SD)	14.68 (27.12)	1.05 (2.61)	<0.001
OCS (med., IQR)	4 (3-4)	4 (4-4)	<0.001
OCS = 4	45 (54%)	78 (94%)	<0.001
App. abx within 24h	62 (75%)	82 (99%)	<0.001
Repeat bld. cx	67 (81%)	82 (99%)	<0.001
Duration assessment	75 (90%)	80 (96%)	0.119
App. duration	66 (80%)	79 (95%)	0.002
ID cons.	61 (73%)	82 (99%)	<0.001
Death or relapse	13 (16%)	3 (4%)	0.009

Conclusion: Antimicrobial stewardship intervention had a positive impact, not only on management of SAB, but also on mortality and relapse. Our data demonstrate a bundled approach can be effective in a community teaching hospital.