Central line-associated bloodstream infection

Central line-associated bloodstream infection is defined by the U.S. Centers for Disease Control and Prevention (CDC) as a primary bloodstream infection occurring in a patient with a central line at the time of or within 48 hours before the infection, with no other apparent source. The catheter disrupts the skin barrier and provides a surface for microbial adhesion and biofilm formation, allowing skin flora—most commonly coagulase-negative staphylococci, Staphylococcus aureus, and Candida species—to migrate extraluminally along the catheter tract or intraluminally through the hub. Biofilm-embedded organisms resist both host defenses and antimicrobial therapy, making catheter removal often necessary for cure.¹

CLABSIs are among the most common healthcare-associated infections, with an estimated 30,000 cases annually in U.S. intensive care units (ICUs) alone, though rates have declined significantly since the early 2000s due to prevention bundles. The attributable mortality ranges from 12% to 25%, and each episode adds an average of $46,000 to hospital costs and prolongs length of stay by up to 19 days. The burden is disproportionately high in low- and middle-income countries, where surveillance and prevention resources are limited. In the United States, the CDC's National Healthcare Safety Network (NHSN) tracks CLABSI rates as a quality metric, and public reporting has driven substantial reductions.²³

Prevention of CLABSI relies on a bundle of evidence-based practices: hand hygiene, maximal sterile barrier precautions during insertion (including cap, mask, sterile gown, and full-body drape), chlorhexidine skin antisepsis, and daily review of catheter necessity with prompt removal of unused lines. Additional measures include using chlorhexidine-impregnated dressings and antimicrobial-coated catheters for high-risk patients, and educating insertion and maintenance teams. The 'central line bundle' introduced by the Institute for Healthcare Improvement (IHI) has been shown to reduce CLABSI rates by more than 60% in ICUs. Compliance with maintenance checklists, such as proper hub disinfection and dressing changes, is equally critical.

Beyond the ICU, CLABSIs occur in outpatient hemodialysis, oncology, and long-term care settings, where peripherally inserted central catheters (PICCs) are increasingly used; these infections are often underreported. A notable edge case is the 'catheter salvage' strategy in which infected lines are retained and treated with antibiotic lock therapy—effective for uncomplicated infections with biofilm-susceptible organisms, but contraindicated in sepsis or with S. aureus. Historically, the first central venous catheter was described by Werner Forssmann in 1929, who inserted it into his own arm, but the infection risk was not systematically studied until the 1970s. The term 'CLABSI' itself was coined to distinguish catheter-related infections from other primary bloodstream infections, and it has been adopted globally for benchmarking.⁴

Central venous catheter

A catheter inserted into a large vein, such as the subclavian or jugular, used for administering fluids, medications, or monitoring.

Biofilm

A community of microorganisms attached to a surface, encased in a protective matrix that resists antibiotics.

Antibiotic lock therapy

A technique where a high concentration of antibiotic is instilled into the catheter lumen to eradicate biofilm.

Bundle

A set of evidence-based practices implemented together to improve patient outcomes.