Impact of monitoring blood volume in the BD BACTEC™ FX blood culture system: virtual volume versus actual volume

• Published in: Diagnostic microbiology and infectious disease 2015-02, Vol.81 (2), p.89-93
• Main Authors: Chang, Jeonghyun, Park, Jeong Su, Park, Sookja, Choi, Byeonghoo, Yoon, Nam Seop, Sung, Heungsup, Kim, Mi-Na
• Format: Article
• Language: English
• Subjects: Adult; Aerobic bottle; Anaerobic bottle; Bacteremia - diagnosis; Bacteriological Techniques - methods; Blood - microbiology; Blood culture; Blood volume; Humans; Infectious Disease; Internal Medicine; Monitoring; Prospective Studies; Sensitivity and Specificity; Specimen Handling - methods; United States
• ISSN: 0732-8893; 1879-0070
• DOI: 10.1016/j.diagmicrobio.2014.11.001

Abstract The BACTEC™ FX (BD, USA) has been recently upgraded to measure virtual blood volume (VV) in batches of 25 PLUS Aerobic/F bottles. VVs were compared with manually measured actual volumes (AVs). The mean AV was larger in anaerobic bottles: 2.6 ± 1.9 mL in 2995 Aerobic/F bottles and 3.3 ± 1.8 mL in 3053 Lytic/10 Anaerobic/F bottles ( P < 0.001). The VV of Aerobic/F bottles was 2.4 ± 1.4 mL, and there was a significant correlation between the VVs and AVs of each department ( P < 0.001). The potential positivity in aerobic bottles increased 1.2-fold with a 1-mL increase in the AV ( P < 0.001). AV and VV were consistently less than adequate. Although the proportional effect of volume on positivity can be proven only with the AV, VVs are a reliable substitute for AVs to monitor the overall blood volumes and provide feedback to the individual departments or locations.