Antimicrobial/Anti-infective Catheters: Comparison of BSI Rates in a Community Hospital

BACKGROUND: Missouri Baptist Medical Center is a 499-bed community hospital with 30 ICU beds and approximately 92,281 patient days per year. Primary bloodstream infection (BSI) rates are monitored in the intensive care unit (ICU) and range from 3.09/1000 to 16.19/1000 central line days (CLD). In 2001 a study was initiated to compare BSI rates among patients with anti-infective (chlorhexidine- and silver-sulfadiazine-coated) catheters versus those with anti-microbial (minocycline and rifampin)-coated catheters. METHODS: The quasi-experimental study included patients from ICU and general patient-care areas (PCA) with multi-lumen catheters. Anti-infective catheters were used during the Phase I of the study from January through June, and anti-microbial catheters were used during the Phase II of the study from July through December. Patients excluded from the study were those with 1 and 4 lumens, those with dialysis catheters, and those with catheters placed by guidewire exchange. BSI rates, line duration, and time to infection were compared by univariate analysis to determine if implementation of antimicrobial catheters decreased infection rates. RESULTS: During the study period, 27 patients developed BSI. Fifteen of the 27 cases were excluded from the study. The BSI rate for the entire study period was 4.79/1000 CLD. BSI rate for Phase I was 4.81, and 4.78 for Phase II. There was no statistically significant difference noted. BSI rates were higher in ICU patients compared to patients in PCA (7.89 and 1.62/1000 CLD, respectively). No statistical difference was found for line duration or time to infection among the catheter types. In all, infected cases the lines were placed in either the subclavian or internal jugular veins. CONCLUSION: There were no statistical differences in BSI rates between Phase I and Phase II. Limitations of the study included sample size bias, which impeded our ability to detect differences in rates due to inadequate power. Although the study was conducted for a full year, the small numbers of infections made it difficult to demonstrate statistical significance. Literature has shown that the use of central venous catheters impregnated with minocycline and rifampin are associated with lower rates of colonization than those coated with chlorhexidine silver sulfadiazine. However these findings were not duplicated in our study.