1997. Impact of Blood Culture Fill Volumes
Session: Poster Abstract Session: Diagnostics: Bacteria and Mycobacteria
Saturday, October 6, 2018
Room: S Poster Hall
Posters
  • Blood Culture Refill Volume Poster.jpg (450.5 kB)
  • Background:

    Historically, increases in blood culture (BC) fill volumes (FVs) have been shown to increase yield of BCs and lower contamination rates. Low FV are a common cause of false negative BCs. 10 mL is considered an ideal FV for a BC. In 2015 and 2016, at North Shore University Hospital, FVs averaged <5 mL per BC. In 2017, several interventions were implemented to increase FVs, including convening informal meetings and seminars to educate nursing staff, educational phlebotomy posters, placing 10-mL markings on BC bottles and using butterfly catheters and tabletops for collection. Our aim was to assess trends in overall yield (OY), contaminants and FVs.

    Methods:

    Average FVs, positive BC quantities and organism identification were obtained from 2015 through 2017. Contaminants included bacillus, corynebacterium, coagulase negative staphylococcus, micrococcus and single sets of alpha-hemolytic streptococcus. OY was the number of positive sets, excluding contaminants, divided by the total number of BCs. Subgroup yield (SY) was the number of positive sets in a subgroup divided by the total number of BCs. Trends in OY, SY, and contaminants were assessed using the Cochran Armitage Trend test. The one-way ANOVA test was used to assess differences between FVs by year.

    Results:

    OY increased over the 2015–2017 period (Table 1; P < .0001). All SYs increased except for staphylococcus and anaerobes. Contaminants did not show a decreasing trend (Table 2; P = 0.9002).

    Table 1. Yield by Year

    Yield, %

    Year

    P Value

    2015

    2016

    2017

    OY

    6.37

    7.57

    8.49

    <.0001

    Total Gram Positivesa

    3.1

    3.52

    3.69

    <.0001

    Staphylococcus

    1.79

    2.01

    1.95

    0.1178

    Enterococcus

    0.66

    0.88

    0.98

    <.0001

    Gram Negative

    2.52

    3.03

    3.64

    <.0001

    Anaerobe

    0.22

    0.24

    0.26

    0.3811

    Fungal

    0.15

    0.28

    0.27

    0.001

    Mixed

    0.28

    0.38

    0.42

    0.0026

    Other

    0.09

    0.12

    0.21

    <.0001

    aIncludes staphylococcus and enterococcus

    Table 2. Mean FV by Year

    Year

    Total BC Ordered, n

    Contaminants, %

    Mean FV (SD), ml

    2015

    35624

    2.87

    4.32 (0.26)

    2016

    38440

    2.99

    4.39 (1.39)

    2017

    37042

    2.88

    6.11 (0.98)

    Conclusion:

    BC FVs successfully increased with interventions implemented. While OY increased each year, an association between yield and FVs could not be determined due to small sample sizes. Further evaluation at quarterly intervals is ongoing and may help establish a correlation.

    Ilan Berlinrut, MD1, Aradhana Khameraj, RN, MSN, CIC2, Rebecca Schwartz, PhD3, Rehana Rasul, MA, MPH4, Pranisha Gautam-Goyal, MD1, Bruce Farber, MD1 and Prashant Malhotra, MBBS, FACP, FIDSA1, (1)Infectious Disease, Northwell Health, North Shore University Hospital, Manhasset, NY, (2)Infection Prevention, Northwell Health, North Shore University Hospital, Manhasset, NY, (3)Department of Occupational Medicine, Epidemiology and Prevention, Zucker School of Medicine at Hofstra-Northwell, Manhasset, NY, (4)Biostatistics, Northwell Health, Feinstein Institute of Medical Research, Manhasset, NY

    Disclosures:

    I. Berlinrut, None

    A. Khameraj, None

    R. Schwartz, None

    R. Rasul, None

    P. Gautam-Goyal, None

    B. Farber, None

    P. Malhotra, None

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