CRBSI Rates May Be Biased by Differences of Blood Culture Sampling and CRBSI Definition

Catheter-related bloodstream infection (CRBSI) surveillance serves as a quality improvement measure that is often used to assess performance. Cherifi, et al. (2013) reviewed the total number of microbiological samples collected in three Belgian intensive care units (ICU) in 2009 to 2010, and described variations in CRBSI rates based on two factors: microbiological documentation rate and CRBSI definition which includes clinical criterion for coagulase-negative Staphylococcus (CNS) episode.

CRBSI rates were 2.95, 1.13 and 1.26 per 1,000 estimated catheter-days in ICUs A, B and C, respectively. ICU B cultured fewer microbiological samples and reported the lowest CRBSI rate. ICU C had the highest documentation rate but was assisted by support available from the laboratory for processing single CNS positive blood cultures. With the exclusion of clinical criterion, CRBSI rates would be reduced by 19 percent, 45 percent and 0 percent in ICUs A, B and C, respectively.

The researchers concluded that CRBSI rates may be biased by differences of blood culture sampling and CRBSI definition. These observations suggest that comparisons of CRBSI rates in different ICUs remain difficult to interpret without knowledge of local practices. Their research was published in Antimicrobial Resistance and Infection Control.

Reference: Cherifi S, Mascart G, Dediste A, et al. Variations in catheter-related bloodstream infections rates based on local practices. Antimicrobial Resistance and Infection Control 2013, 2:10 doi:10.1186/2047-2994-2-10