Prospective Trial of a Passive Diversion Device to Reduce Blood Culture Contamination

Blood culture contaminants can lead to inappropriate antibiotic use, prolonged length of stay, and additional hospital costs. Several devices have been developed to reduce the risk of blood culture contamination by diverting a portion of the initial blood sample from the blood culture bottle. We assessed the effectiveness of 1 blood diversion device (BDD) in a prospective trial performed at the 2 separate emergency departments (EDs) of an academic medical center.

A multiphase prospective crossover trial was performed with the BDD in use at 1 ED and standard equipment at the other ED for 10 weeks, and a second 10-week study phase was conducted with the use of the BDD and standard equipment in the EDs reversed. Contaminants were identified both by standard clinical microbiology lab criteria and by independent retrospective review by 3 infectious disease (ID) physicians. The primary analysis was performed based on intention-to-use data using the physician review of positive blood cultures.

A total of 5637 blood samples were obtained, with 5625 samples analyzed after 12 blood culture results were deemed inconclusive by the ID physician review. The University ED had a higher blood culture contamination rate of 2.9% compared with the Memorial ED at 1.4%. In an intention-to-use analysis, the overall contamination rates were 2.0% and 2.9% in the BDD and standard equipment periods, respectively (P = .03), and in an actual-use analysis the contamination rates were 1.2% and 3.0% for the BDD and standard equipment, respectively (P < .001).

The BDD was associated with significantly lower blood culture contamination rates at the institution's 2 EDs, with a stronger effect noted at the campus caring for higher acuity patients.