What are the latest guidelines for the treatment of Central Line-Associated Bloodstream Infections (CLABSI)?

Treatment of Central Line-Associated Bloodstream Infections (CLABSI)

The management of CLABSI requires pathogen-specific antimicrobial therapy combined with strategic decisions about catheter removal based on the causative organism, clinical severity, and catheter type.

Initial Empirical Antimicrobial Therapy

• Start broad-spectrum IV antibiotics immediately covering both gram-positive organisms (including MRSA) and gram-negative pathogens before culture results are available 1
• Vancomycin 15-20 mg/kg IV every 8-12 hours PLUS an anti-pseudomonal beta-lactam (such as cefepime, piperacillin-tazobactam, or meropenem) should be initiated empirically 1
• Adjust therapy based on culture results and antimicrobial susceptibilities once available 1

Catheter Removal: Mandatory Indications

Immediate catheter removal is required for CLABSI caused by the following organisms 1:

• Staphylococcus aureus (including MRSA)
• Pseudomonas aeruginosa
• Fungi (any Candida species)
• Mycobacteria
• Bacillus species
• Micrococcus species
• Propionibacteria

Catheter removal is also mandatory in these clinical scenarios 1:

• Severe sepsis or hemodynamic instability
• Suppurative thrombophlebitis
• Endocarditis
• Tunnel infection or port pocket infection
• Persistent bacteremia >72 hours despite appropriate antimicrobial therapy
• Septic thrombosis

Catheter Salvage Strategy

For coagulase-negative staphylococci CLABSI in long-term catheters, catheter retention may be attempted using systemic antibiotics with or without antibiotic lock therapy 1

Requirements for Catheter Salvage:

• Pathogen must NOT be S. aureus, P. aeruginosa, fungi, or mycobacteria 1
• No signs of severe sepsis or hemodynamic instability 1
• No tunnel infection, port pocket infection, or endocarditis 1
• Patient must be closely monitored with repeat blood cultures 1

Antibiotic Lock Therapy Protocol:

• Use in conjunction with systemic antibiotics for catheter salvage attempts 1
• Lock solution should remain in the catheter for 24-hour dwell times 2
• Continue for 14 days total 2
• Obtain repeat blood cultures 72 hours after initiating therapy 1
• Remove catheter if blood cultures remain positive at 72 hours 1

Duration of Antimicrobial Therapy

Uncomplicated CLABSI:

• 14 days minimum of systemic antimicrobial therapy after catheter removal for S. aureus, P. aeruginosa, fungi, or mycobacteria 1
• 10-14 days for gram-negative organisms after catheter removal 1
• 7-10 days for coagulase-negative staphylococci if catheter is removed 1

Complicated CLABSI:

• 4-6 weeks of antimicrobial therapy is required for 1:
  • Deep tissue infection
  • Endocarditis
  • Septic thrombosis
  • Persistent bacteremia or fungemia >72 hours after catheter removal despite appropriate antimicrobials

Pathogen-Specific Management

Staphylococcus aureus CLABSI:

• Always remove the catheter 1
• Obtain transesophageal echocardiography (TEE) to exclude endocarditis 3
• Minimum 14 days of therapy if TEE is negative and catheter removed 3
• Extend to 4-6 weeks if endocarditis or persistent bacteremia present 1

Coagulase-Negative Staphylococci:

• Catheter may be retained in long-term catheters with systemic therapy ± antibiotic lock therapy 1
• Remove catheter if bacteremia persists >72 hours on appropriate therapy 1

Gram-Negative Organisms (Pseudomonas, Enterobacter, Klebsiella, E. coli):

• Remove catheter for Pseudomonas aeruginosa 1
• For other gram-negatives, catheter removal is strongly recommended but salvage may be attempted in select cases with limited vascular access 1
• 10-14 days of appropriate systemic therapy after catheter removal 1

Fungal CLABSI (Candida species):

• Mandatory catheter removal 1
• Echinocandin preferred for initial therapy 3
• Minimum 14 days after first negative blood culture and catheter removal 1

Diagnostic Approach

Blood Culture Technique:

• Obtain at least 2 sets of blood cultures: one from the catheter and one from a peripheral vein 1
• Differential time to positivity (DTP) >120 minutes between catheter and peripheral cultures suggests CLABSI 1
• For hemodialysis catheters, peripheral blood samples should be obtained from vessels not intended for future fistula creation 1

Additional Diagnostic Steps:

• Culture any purulent drainage from exit site 1
• Send catheter tip for culture if catheter is removed 1
• Consider imaging (CT with contrast) if deep abscess or septic thrombosis suspected 3

Special Populations

Hemodialysis Patients:

• Always remove catheter for CLABSI due to S. aureus, Pseudomonas species, or Candida species 1
• Insert temporary catheter at different anatomical site 1
• Long-term catheter can be placed once blood cultures are negative 1

Pediatric Patients:

• Indications for catheter removal are similar to adults 1
• Catheter salvage may be considered more liberally given difficulty of obtaining alternate venous access 1
• Close monitoring with clinical evaluation and repeat blood cultures required if catheter retained 1
• Antibiotic lock therapy should be used for catheter salvage attempts 1

Neutropenic/Oncology Patients:

• Same principles apply regarding catheter removal for high-risk organisms 1
• Catheter salvage may be attempted for coagulase-negative staphylococci given limited access sites 1

Monitoring and Follow-up

• Obtain repeat blood cultures 72 hours after initiating therapy 1
• Remove catheter if cultures remain positive at 72 hours 1
• Monitor for clinical improvement: resolution of fever, hemodynamic stability 3
• Assess for complications: endocarditis, septic thrombosis, metastatic infection 1
• For S. aureus bacteremia, obtain TEE to exclude endocarditis 3

Prevention Strategies

• Hand hygiene is the most effective means of preventing CLABSI 1
• Use maximal sterile barrier precautions during catheter insertion 1
• Cutaneous antisepsis with chlorhexidine during insertion 1
• Remove catheters as soon as clinically appropriate 1

Critical Pitfalls to Avoid

• Never attempt catheter salvage for S. aureus, P. aeruginosa, fungi, or mycobacteria 1
• Do not delay catheter removal in hemodynamically unstable patients 1
• Avoid inadequate duration of therapy—minimum 14 days for high-risk organisms 1
• Do not fail to obtain adequate blood cultures before starting antibiotics 1
• Never continue catheter salvage if bacteremia persists >72 hours on appropriate therapy 1
• Ensure vancomycin trough levels are therapeutic (15-20 mcg/mL for serious infections) as subtherapeutic levels are associated with treatment failure 4