A recent article in MedicalLab Management, authored by Mayo Clinic staff, discusses how to sustain reduced blood-culture contamination. According to the article, blood-culture contamination remains a problematic cause of false positives and diagnostic errors for many clinical laboratories.
According to the College of American Pathologists (CAP), a blood culture is considered contaminated if one or more of the following organisms are identified in only one culture of a series of specimens in a 24-hour period:
Further, CAP has established a blood-culture contamination rate threshold of 3% for corrective action.
However, laboratory leadership at Mayo Clinic Health System–Franciscan Healthcare (MCHS-FH) in La Crosse, Wisconsin, felt the lab could, and should, establish a more stringent threshold than 3% after accounting for the cost-of-poor-quality (COPQ) impacts on patients.
Laboratory leadership observed the practices of senior phlebotomists who had produced no contaminated cultures during a set observation period, and implemented those techniques, coupled with best practices found in literature, as the standard operating procedures for phlebotomy. Exemplary staffers also were asked to help train coworkers on contamination countermeasures that included:
Contamination rates fell significantly. In 2014, the laboratory had a total of 93 contaminated blood cultures out of 5,784 collected, equaling a contamination rate of 1.6%. Over the course of 2015, there were a total of 79 contaminated cultures out of 5,863 collected, further reducing the contamination rate down to 1.3%. (Anything below 1% is considered improbable due to uncontrollable factors such as transient bacteremia.)
Read the full article to learn more.