How to achieve accurate blood culture volumes: the BD BACTEC FX blood volume monitoring system as a measuring instrument and educational tool

Collecting adequate volumes of blood in blood culture bottles is crucial for sensitive detection of bacteremia and fungemia. Tools enabling easy collection of data on the degree of blood culture bottle filling at different hospital departments are an important step toward quality measurement and improvement. In this study, we verified the accuracy of a software tool for the monitoring of blood culture bottle filling developed by Becton Dickinson, BD blood volume monitoring system (BVMS) that was adjusted for use on plastic BACTEC bottles, and evaluated its ease of use in routine practice. In total, 538 negative plastic BD BACTEC Plus Aerobic/F blood culture bottles collected in two secondary care hospitals in Belgium were included in the study. The BVMS software demonstrated good performance, with an acceptable mean difference of − 0.3 mL or − 4.0% between the mean volume estimated by BVMS and the mean weight-based volume. Data (mean blood volume and standard deviation) and figures (box-and-whisker and histogram plots) on blood culture bottle filling are easily acquired. They provide information on the current situation in a hospital (department) and can be used as a tool for quality improvement measurements and follow-up. Caution is required when interpreting BVMS results for hospital wards where a substantial amount of the bottles collected come from patients with hematocrit values < 30%. This study demonstrated that BVMS is a reliable and easy to use tool which facilitates monitoring and coordination of optimization of blood culture bottles filling by the clinical laboratory.