Central-Line Associated Bloodstream Infection (CLABSI) B Rates – Low for Years then the Pink Pathogens Appear

 Background:  In 2002 UPMC-Presbyterian, a 766 bed university hospital with a case mix index of 2.29 focused on perfecting CL insertion practices and achieved a 77% ICU CLABSI rate reduction (5.2 to 1.2/1000 CL days). Rates further decreased to ≤1 with the nadir of 0.6 in 2007. Since 9/06, house wide (HW) CLABSI rates have been collected with an aggregate rate ≤ 0.7. Reduction was attributed to near perfect compliance with the CL insertion bundle and gram positive (GP) skin flora pathogens were reduced.  There have been multiple studies suggesting an association between positive displacement needleless connectors (PDNCs) and higher CLABSI rates. In 8/10 the FDA had concerns about the device safety and issued a notice asking for CLABSI analysis. In 3/08, Carefusion SmartSite (CFSS) needleless connectors were implemented. While rates remained relatively low, pathogen predominance switched from GP to gram negative (GN). In an attempt to decrease GN CLABSIs, SwabCap™ (SC) were implemented in 12/09.

 

Objective: To determine if the GP and/or GN CLABSIs rate had changed after the introduction of CFSS or SC Luer Access Valve Disinfection Cap.

Methods:  HW CLABSIs were defined using NHSN criteria. Monthly CLABSI rate were trended. CLABSIs were stratified by GP and GN pathogens. The 49 month study period was divided into 3 periods. Period 1 was the baseline when CL bundle was used. Period 2 was CL bundle + CFSS and period 3 was CL bundle + CFSS + SC. An interrupted time series analysis was done using segmented regression analysis.

 

Results:

GP CLABSI Rate		GN CLABSI Rate
Baseline Level	1.196	Baseline Level	0.342
Slope Trend in Period 1	-0.046 (p=0.003)	Slope Trend in Period 1	-0.005 (p=0.56)
Period 2 vs. Period 1
Level Change	-0.024 (p=0.91)	Level Change	0.013 (p=0.92)
Change in Trend in Period 2	0.043 (p=0.03)	Change in Trend in Period 2	0.02 (p=0.08)
Slope Trend in Period 2	-0.003	Slope Trend in Period 2	0.015
Period 3 vs. Period 2
Level Change	0.072 (p=0.78)	Level Change	-0.394 (p=0.01)
Change in Trend in Period 3	0.015 (p=0.68)	Change in Trend in Period 3	0.016 (p=0.47)
GP CLABSIs - In period 1 and 2 there were significant slope changes but there was no significant difference in   period 3.  GN CLABSI – In period 1 there was no significant slope change. In period 2, the slope changed but not significantly.  In period 3 the slope did not change significantly but the base rate did drop significantly by 0.394.

Conclusions:

During period 1, GPs accounted for most CLABSIs and was most affected by the reduction efforts whereas the GN CLABSI rate was low and unchanged. During the CFSS period, the GP CLABSI rate continued to decrease while the GN CLABSI rate increased. After implementing the SC, only the GN CLABSI rate dropped significantly. SC appears to help decrease GN CLABSIs but did not change the already low GP CLABSI rate.