CLABSI

Confirmation of central-line associated bloodstream infections requires all of:

The CLABSI rate is a key marker of ICU quality and is reported as number of infections per 1000 central line-days.

Epidemiology and Risk Factors

Invasive lines are a major cause of nosocomial infections, causing ~65% of bloodstream infections. Risks depend on:

  • Duration of line insertion
  • Site
    • Femoral possibly highest risk
    • Subclavian possibly lowest risk
  • Line features
    • Non-antimicrobial coated
    • Number of lumens
    • Frequency of access
    • Overly frequent or infrequent dressing changes
  • Type of line
    In descending order:
    • PA catheter
      3.7/1000 line-days.
    • Non-tunneled CVC
      2.7/1000 line-days.
    • Arterial line
      1.7/1000 line-days.
    • Tunneled CVC 1.6/1000 line-days.
    • PICC line 1.1/1000 line-days.
    • Peripheral IVC 0.5/1000 line-days.
    • Midline 0.2/1000 line-days.
  • Colonisation
    Occurs in 5-40% of catheters. Colonisation is a risk factor for infection, but is otherwise of no consequence.

Pathophysiology

Aetiology

A positive blood culture taken from an existing CVC indicates one of:

  • Benign line colonisation
    • Colonisation without bacteraemia
    • Common
      10-25% of lines.
  • Bacteraemia secondary to line colonisation
    i.e. True CLABSI.
  • Bacteraemia with independent to line colonisation
    The bacteraemia is not from the line, and the line may or may not be colonised.
Causative and Cultured Organisms
Probable Bacteraemia Probable Colonisation
Gram Positive Cocci
  • Coagulase-positive staphylococci
    • S. aureus
  • Strep. pneumoniae
  • Strep. pyogenes
  • Strep. agalactiae
  • Coagulase-negative staphylococci
    • S. epidermidis
    • S. haemolyticus
    • S. hominis
    • S. saprophyticus
    • S. lugdunensis
  • Viridans streptococci
    • S. mitis
    • S. sanguinis
    • S. oralis
  • Enterococci
  • Micrococcus spp.
Gram Positive Bacilli
  • Listeria monocytogenes
  • Corynebacterium spp.
  • Bacillus spp.
    Other than anthracis.
  • Propionibacterium acnes
  • C. perfringens
Gram Negative Cocci
  • N. meningitidis
  • N. gonorrhoeae
  • H. influenzae
Gram Negative Bacilli
  • E. coli
  • Enterobacteriaceae
  • P. aeruginosa
  • Bacteroides fragilis
Fungi
  • Crytptococcus neoformans
  • C. albicans
Notes Bacteraemia predominantly match patient endogenous flora 25% of colonisation is by coagulase-negative Staphylococci.

Clinical Manifestations

Diagnostic Approach and DDx

Investigations

Laboratory:

  • Blood cultures

Management

Specific therapy:

  • Pharmacological
    • Antimicrobials
      Agent and duration depends on causative organism:
      • Coagulase-negative Staphylococcus: 5 days
      • S. Aureus: 14 days
      • Candida: 14 days
  • Procedural
    • Remove line
      Line tips should be sent for culture if it suspected as the source for infection.
  • Physical

Preventative:

  • Rationalise line insertion
  • Antibiotic coated lines for immunocompromised patients
  • Aseptic insertion and management
    • Policy around insertion
    • Securing of line to prevent tract inoculation
    • Sterile line dressings
    • Daily line inspection
    • 7-daily dressing changes
  • Dedicated lumen for lipid infusions

Routine changing of lines based solely on catheter-days is not indicated.

Marginal and Ineffective Therapies

Anaesthetic Considerations

Complications

Prognosis

Key Studies

References

  1. Bersten, A. D., & Handy, J. M. (2018). Oh’s Intensive Care Manual. Elsevier Gezondheidszorg.
  2. O’Grady NP, Barie PS, Bartlett JG, et al. Guidelines for evaluation of new fever in critically ill adult patients: 2008 update from the American College of Critical Care Medicine and the Infectious Diseases Society of America. Critical Care Medicine. 2008;36(4):1330.