Learning Objective #1: State consequences of blood culture contamination

Learning Objective #2: List evidence based practices to reduce blood culture contamination

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Blood culture contamination is associated with an increased length of stay of 4.5 days, adding an additional $ 5000 to the treatment cost (Bates et.al, 1991; Ernst, 2004).The national benchmark generated by the College of American Pathologists Q-track survey is 3.0% (90th percentile). Nevertheless, in many teaching hospitals the contamination rates exceed this rate (Bates 1991, Mimoz 1999, Strand et. al. 1993) Problem: The mean contamination rate from April 2003-2004 was 3.21% in MICU while the goal was 2.5 % (95th percentile). Additionally a pre-test indicated a knowledge deficit concerning the best practice methods and consequences of blood culture contamination. Research literature from clinical microbiology, internal medicine, and nursing indicated that current practice guidelines for the unit were consistent with best practice recommendations. Intervention: A brief educational intervention with a storyboard was developed highlighting the scope of the problem and evidence based practices to reduce blood culture contamination. Additionally, the project members reviewed the cases of contaminated blood cultures to identify other factors contributing to this problem. Findings: Scores on the posttest were 87-100% compared to 53%-87% on the pretest. Tracking the contaminated cultures was a difficult task due the lack of set standards in data collection. A unit-based log was instituted to match patients and RN with culture contamination results. Outcome: The contamination rate dropped to 2.7% when the cultures were procured by MICU RNs and each contaminated culture could be tracked and the source identified. Challenges for the future include sustaining the change, improving data collection and reporting, identifying other factors contributing to the problem, ensuring that new staff are oriented to the procedure and spreading the change to other critical care units.