Blood volume collected for cultures in infants with suspected neonatal sepsis.

ABSTRACT

OBJECTIVES: To evaluate blood culture sample volumes, identify factors linked to insufficient samples, and compare volumes among neonates treated for culture-negative-sepsis, sepsis-rule-outs, and bloodstream infections (BSI). METHODS: Observational cohort of blood cultures collected during NICU stay. Association of age, weight, gender, source, and collection time with lower-than-recommended volumes was determined by logistic regression. Blood culture inocula of patients with culture-negative-sepsis, sepsis rule-out, and BSI were compared using ANOVA. RESULTS: 742 blood cultures were obtained from 292 neonates. Median inoculum was 1 mL (IQR0.6-1.4), and 259 bottles (35%) had inocula <0.9 mL. Night shift sample collection was associated with lower-than-recommended volumes (p = 0.006). No difference in sample volumes was observed between culture-negative-sepsis, sepsis-rule-outs, and BSI (p = 0.5). CONCLUSIONS: Median NICU blood culture volumes align with recommendations. Night shift collections correlate with lower volumes. Sample volumes don't differ in patients with culture-negative-sepsis, BSI, and sepsis-rule-out, and should not be a justification for longer duration of antibiotics.