Device Utilization and Pathogen Distribution of Central Line-Associated Bloodstream Infections in Adult Non-Acute Care Units: A Report from the National Healthcare Safety Network, 2006-2008

Background: Historically, central line-associated bloodstream infection (CLABSI) data submitted by healthcare facilities to the Centers for Disease Control and Prevention (CDC) were limited to infections occurring in intensive care unit (ICU) patients. However, facilities participating in the CDC’s National Healthcare Safety Network (NHSN) are increasingly reporting non-ICU CLABSI data. As use of central lines moves outside of ICU locations, extending CLABSI surveillance to these patient-care areas is increasingly important.

Objective: To determine whether incidence and characteristics of CLABSI are different in non-ICU compared to ICU locations.  

Methods: We calculated pooled incidence of CLABSI/1000 central line days by location type for 2006-2008. We determined incidence density ratios (IDRs) and device utilization ratios (DURs) for medical, medical-surgical, and surgical wards compared to respective ICUs. The analysis accounted for type of hospital (teaching and non-teaching) and ICU size (small (<=15 beds) and large (>15 beds)). The chi-square test was used to evaluate pathogen distributions. 

Results: The number of CLABSIs reported from non-ICU locations increased from 361 reported by 24 facilities in 2006 to 1625 reported by 197 facilities in 2008. During 2006-2008, the majority of CLABSIs were reported from medical-surgical wards (1070; 44.6%), followed by medical wards (562; 23.4%) and surgical wards (246, 10%). Overall, non-ICUs had lower CLABSI incidence compared to ICU locations: IDR was 0.6 (95%CI 0.5-0.7) for surgical wards vs. surgical ICUs; 0.6 (95%CI 0.5-0.7) for medical wards vs. medical ICUs in major teaching hospitals and 0.9 (95%CI 0.8-1.0) for medical wards vs. medical ICUs in non-teaching hospitals. In major teaching hospitals, the IDR was 0.6 (95%CI 0.5-0.7) for medical-surgical wards vs. medical-surgical ICUs; in non-teaching hospitals, the IDR for medical-surgical wards was 0.9 (95%CI 0.8-1) compared to small and 0.8 (95%CI 0.7-0.9) compared to large medical-surgical ICUs. Differences in commonly reported pathogens included significantly higher proportions of Staphylococcus aureus (18.2% vs. 9.1%, p<0.01) from wards CLABSIs compared to ICUs, while less Enterococcus spp. (14.1% vs. 20.3%, p<0.01) and Candida spp. (12.5% vs. 16%, p<0.01) from wards compared to ICUs.

Conclusions: Incidence of CLABSIs was 10%-60% lower in surgical and medical non-ICU locations compared to their ICU counterparts and very similar in medical-surgical wards compared to medical-surgical ICUs. Translating these rates to total disease burden will help to quantify potential impact of prevention efforts in these settings.