A Diagnostic Stewardship Intervention To Improve Blood Culture Use among Adult Nonneutropenic Inpatients: the DISTRIBUTE Study

Abstract

Interventions to optimize blood culture (BCx) practices in adult inpatients are limited. We conducted a before-after study evaluating the impact of a diagnostic stewardship program that aimed to optimize BCx use in a medical intensive care unit (MICU) and five medicine units at a large academic center. The program included implementation of an evidence-based algorithm detailing indications for BCx use and education and feedback to providers about BCx rates and indication inappropriateness. Neutropenic patients were excluded. BCx rates from contemporary control units were obtained for comparison. The primary outcome was the change in BCxs ordered with the intervention. Secondary outcomes included proportion of inappropriate BCx, solitary BCx, and positive BCx. Balancing metrics included compliance with the Centers for Medicare and Medicaid Services (CMS) SEP-1 BCx component, 30-day readmission, and all-cause in-hospital and 30-day mortality. After the intervention, BCx rates decreased from 27.7 to 22.8 BCx/100 patient-days (PDs) in the MICU (P = 0.001) and from 10.9 to 7.7 BCx/100 PD for the 5 medicine units combined (P < 0.001). BCx rates in the control units did not decrease significantly (surgical intensive care unit [ICU], P = 0.06; surgical units, P = 0.15). The proportion of inappropriate BCxs did not significantly change with the intervention (30% in the MICU and 50% in medicine units). BCx positivity increased in the MICU (from 8% to 11%, P < 0.001). Solitary BCxs decreased by 21% in the medicine units (P < 0.001). Balancing metrics were similar before and after the intervention. BCx use can be optimized with clinician education and practice guidance without affecting sepsis quality metrics or mortality.

Keywords: bacteremia; blood culture; diagnostic stewardship; indications.

FIG 1

Trends of blood cultures in the intervention and control units during the study period. Arrows indicate the intervention. Black solid lines indicate average blood culture rate, and each black circle indicates average blood culture rate for each month. Upper and lower dashed gray lines indicate “control” limits (average rate + [3 × SD]).