Clinical effectiveness and risk of emerging resistance associated with prolonged use of antibiotic-impregnated catheters: more than 0.5 million catheter days and 7 years of clinical experience.

OBJECTIVES: Catheters coated with minocycline and rifampin are proven to decrease the rates of central line-associated bloodstream infection; however, it is unclear whether success occurs independent of other infection control precautions. We evaluated the effect of catheters coated with minocycline and rifampin with and without other infection control precautions on our rates of central line-associated bloodstream infection in critically ill patients and on antibiotic resistance throughout the hospital and in the intensive care unit.
DESIGN: Retrospective clinical cohort study conducted during 1999-2006 with an observational laboratory component.
SETTING: A tertiary university-based cancer center. PATIENTS: All 8009 patients admitted to the medical intensive care unit were subjects for the surveillance of central line-associated bloodstream infection. All Staphylococcus aureus and coagulase-negative staphylococci clinical isolates cultured at our institution during the same period were subjects for laboratory testing.
INTERVENTIONS: Using catheters coated with minocycline and rifampin and implementing infection control precautions.
MEASUREMENTS AND MAIN RESULTS: Incidence of central line-associated bloodstream infection in the medical intensive care unit. Change in resistance to tetracycline and rifampin in clinically relevant staphylococcal isolates in the intensive care unit and hospitalwide. During the study period, 9200 catheters coated with minocycline and rifampin were used hospitalwide over a total of 511,520 catheter days. The incidence of central line-associated bloodstream infection per 1000 patient days in the medical intensive care unit significantly and gradually decreased from 8.3 in 1998 to 1.2 in 2006 (p ≤ .001). The resistance of S. aureus and coagulase negative staphylococci clinical isolates to tetracycline or rifampin in the intensive care unit and on a hospitalwide level remained stable or decreased significantly during the same period.
CONCLUSIONS: Catheters coated with minocycline and rifampin significantly decreased the incidence of central line-associated bloodstream infection in the medical intensive care unit in a manner that was independent and complementary to the infection control precautions. Although this study strongly suggests an association between catheters coated with minocycline and rifampin use and a decrease in central line-associated bloodstream infection, because of multiple other concurrent interventions, the results should be interpreted cautiously until a prospective study is conducted. Furthermore, long-term use of these devices is not associated with increased resistance of staphylococcal isolates to tetracycline and rifampin in the intensive care unit or throughout the hospital.