Origins of the CLAB definition

1
Origins of the CLAB definition

• AICA National Advisory Board 2001-2 adapted
  National Nosocomial Infection System definition
  with minor clarification
• Endorsed National Quality and Safety Council 2004
• NSW Health Infection control program quality
  monitoring indicators, version 1(2003) 2
  (current) all hospitals with ICUs report
• CLAB rates in ICUs (stratified by peripherally
  and centrally-inserted) currently per 1,000
  line-days
• Multi-resistant bacterial events in ICU (MRSA,
  MR-Acinetobacter baumannii)

2
Blood Stream Infection Detection and
Categorisation

• Pathogenesis of central line infection
• Contamination of line tip during insertion
  (commonest)
• Hub contamination (occurs during line
  disconnection etc)
• Infusate contamination (unusual)
• Detection of bacteraemia/fungaemia
• Blood culture collection
• Line tips- not recommended/required
• 3. Categorisation of positive blood culture
  events
• Is the isolate significant?
• Is it a new unique event?
• Is the event ICU-associated?
• Is the event intravascular-line associated?

3
Detection of bloodstream infection

• Detection of bacteraemia/fungaemia in adults is
  dependent on volume of blood at least 40mLs
  recommended (2 x independently collected sets
  best practice)
• Collection via old lines (IA or Central)
  potential for contamination from hub and/or
  infection of line- not recommended.
• Persistently febrile patients (eg. neurosurgical)
  will require regular blood cultures (eg. every 48
  hrs) - single set acceptable
• Collection technique
• alcohol skin disinfection (wet site well, allow
  30 seconds for action),
• no-touch needle insertion,
• best to use vacutainer sleeve for blood culture
  bottle,
• do not overfill bottles

4
Detection of line infection

• Ensure appropriate blood culture collection
  (above)
• Examine line exit sites daily for exudate and/or
  inflammation
• If line sepsis suspected, submit aseptically
  collected line tip for semi-quantitative culture
• No routine requirement for culture of line tips
  in asymptomatic patients

5
Is an isolate significant?

• criterion 1 recognised pathogen
• No clinical correlate required. Single blood
  culture set accepted.
• criterion 2 common skin contaminant (criterion
  3 children lt 1 year with common skin
  contaminant)
• Symptoms of infection
• AND EITHER
• 2 sets positive with the same isolate within
  48hrs (some sort of micro ID required of CNS not
  mixed CNS)
• OR (only for potential CLAB events)
• 1 set positive and appropriate antimicrobial
  therapy is commenced against that isolate

6
Significance accepted pathogens

• 1 positive set acceptable
• Primary events treatment and/or line removal
  instigated
• Diagnosed focus events symptoms/signs of
  infection at a particular primary site
  (microbiological confirmation not required)
• EXCLUDE
• events where no treatment given or action taken
  and patient remained well at 7 days

7
What are common skin contaminants?

• Coagulase negative staphylococci
• Bacillus species
• Corynebacterium species
• Rarely
• Micrococci
• Propionobacterium species
• Environmental Gram negative bacteria

8
Is it a unique (new) event?

• 14 day rule repeat similar blood isolate events
  within 14 days are disregarded

9
Is the event ICU-associated?

• Defined as a significant blood event that is
  detected more than 48 hrs after ICU admission
  where the patient was not overtly infected upon
  admission
• Also includes events detected within 48 hrs of
  patient discharge from ICU

10
Is the event line-associated?

• Requirements include
• No other diagnosed/likely source of sepsis
• Intravascular line present within 48 hr of
  detection
• In an ICU Patient with multiple sites of
  potential active infection, do not classify as
  line-associated unless direct evidence of line
  infection and/or multiple positive blood cultures
  with CNS
• Patient with multiple lines, in the absence of
  direct line site/tip culture evidence to
  associate one line with the event, then assume
  central line is responsible gt IA line gt
  peripheral

11
Blood culture review requirements

• All positive cultures require careful review,
  including events in non-ICU patients within the
  hospital
• For ICU, classify
• Contaminant events
• ICU-associated events due to other infective
  sites
• ICU line-associated events
• Community acquired events
• Need a surveillance system that classifies events
  in the same manner over time eg. look at
  significant shifts in classification of coag neg
  staph event significance

12
Coag neg staph issues
13
Liaison possibilities with Microbiology/IC/ ID

• Classification of blood events in d/w ICU
  clinician(s)
• Micro/Infectious Diseases ICU Rounds antibiotic
  advice, review of microbiology
• Routine periodic review of events that have
  occurred with ICU group
• Capacity to complete the BSI part of the CLAB
  checklist form providing data on events post ICU
  discharge (but would require a duplicate central
  line form in order for the form to remain in the
  medical record at ICU discharge)