VentilatorAssociated Pneumonia

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Ventilator-Associated Pneumonia
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Introduction

• Definition
• 48 hours after intubation
• mechanically ventilated
• No clinical evidence of pneumonia prior to
  intubation
• Time of onset of pneumonia is important
• specific pathogens and outcomes
• Early-onset VAP (lt4 days)
• better prognosis, antibioticsensitive
• Late-onset VAP (5 days or more)
• MDR pathogens
• increased patient mortality and morbidity.

ATS/IDSA Guidelines Guidelines for the
management of adults with VAP
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Pathogenic mechanisms
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Diagnosis and Epidemiology

• Difficult
• Based on clinical indicators such as new or
  persistent infiltrates and purulent sputum
• Invasive bronchoscopic quantitative methods (
  brush and bronchoalveolar lavage) more
  precisely
• invasive, expensive, and may be less useful in
  patients with antibiotics
• quantitative cultures are not available in all
  hospitals.

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ATS/IDSA Guidelines Guidelines for the
management of adults with VAP

• Evidence-based guideline
• Early, appropriate antibiotics in adequate doses
• Avoiding excessive antibiotics
• Based on microbiologic cultures, clinical
  response, shortening the duration to the minimum
  effective period.

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Major epidemiologic points

• Polymicrobial especially in ARDS (Level I)
• Aerobic
• G(-) bacilli (P. aeruginosa, K. P, and
  Acinetobacter species)
• G() cocci (S. aureus, much of which is MRSA)
• Anaerobes are an uncommon cause (Level II)
• Nosocomial virus and fungus are uncommon in
  immunocompetent patients. (Level I)
• MDR pathogens
• severe, chronic underlying disease, late-onset
• varies by patient population, and type of ICU
  (Level II)

ATS/IDSA Guidelines Guidelines for the
management of adults with VAP
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Risk factors for VAP

• Duration of mechanical ventilation
• Aspiration of gastric contents
• COPD
• Use of PEEP
• Reintubation
• Duration of hosptalization
• Supine head positioning
• (head of bed not elevated)
• Fall or winter season
• Nasal intubation or sinusitis

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Modifiable Risk Factors and
Recommendation

• Intubation and mechanical ventilation
• Aspiration, body position and enteral feeding

ATS/IDSA Guidelines Guidelines for the
management of adults with VAP
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Modifiable Risk Factors and
Recommendation

• Modulation of colonization oral antiseptics and
  antibiotics
• Stress bleeding prophylaxis, transfusion and
  glucose control

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Recommendations for the clinical strategy.

• Tracheal aspirate Gram stain can be direct
  initial therapy
• A negative tracheal aspirate has a strong value
  (94 )
• progressive radiographic infiltrate 23
  clinical features represent the most accurate
  clinical criteria.
• Re-evaluation of using antibiotics based on the
  results of semi-quantitative, by Day 3 or sooner
  (Level II)

ATS/IDSA Guidelines Guidelines for the
management of adults with VAP
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Recommendations for initial antibiotic therapy

• Select an initial empiric therapy based on risk
  factors for MDR
• Local microbiology, cost, availability, and
  formulary restrictions
• For patients who have recently received an
  antibiotic? a different antibiotic class

ATS/IDSA Guidelines Guidelines for the
management of adults with VAP
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Initial antibiotic therapy MDR risk factor
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Initial antibiotic therapy
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Recommendations for optimal antibiotic therapy

• Aerosolized antibiotics not been proven (Level
  I)
• MDR with poor response as adjunctive therapy
  (Level III)
• Combination therapy at initial
• Though no data compared with monotherapy
• aminoglycoside regimen, stopped after 5-7 days
  (Level III)
• If appropriate antibiotic, shorten the duration
  of therapy as 7 days (not P. aeruginosa !)
  (Level I).

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Recommendations for selected MDR pathogens

• Combination therapy is recommended.
• Resistance ?on monotherapy
• Appropriate and effective (Level II)
• Acinetobacter carbapenems, sulbactam, colistin,
  polymyxin.
• ESBL Enterobacteriaceae monotherapy of
  carbapenems (Level II)
• Adjunctive therapy ( inhaled aminoglycoside or
  polymyxin) for MDR G(-) (Level III)
• Linezolid is an alternative to vancomycin
• MRSA, renal insufficiency, nephrotoxic agents
  (Level III).

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• Ventilator Circuit Change and VAP
• UpToDate November 16, 2005

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Ventilator circuit change

• Most important routes of bacterial invasion
• aspiration of oropharyngeal secretions
• inhalation of aerosols containing bacteria
• Common colonization of circuits with large
  numbers of microorganisms.
• Circuits were changed daily? 23 days?
• not a benign procedure, particularly for
  critically ill patients.
• Cost and time !!

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Summary of Studies
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Recommendations

• Recommend that ventilator circuits can be changed
  at weekly
• Less frequent intervals without increasing the
  risk of VAP
• Required if gross soiling with blood or vomitus
  occurs
• The impact upon VAP is presently unclear for
  issues
• heated versus unheated circuits
• artificial noses versus heated humidifiers.

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• Summery

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Summery

• MDR pathogens
• A lower respiratory tract culture needs to be
  collected
• Negative cultures stop antibiotic therapy
• An empiric therapy regimen should include agents
  that are from a different antibiotic class than
  the patient has recently received.

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Summery

• Combination therapy and short-duration (5 days)
• P. aeruginosa aminoglycoside ß-lactam
• Linezolid is an alternative to vancomycin, for
  proven MRSA.
• Aerosolized antibiotics to MDR pathogens.
• Ventilator circuits changed at weekly

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References

• ATS/IDSA Guidelines Guidelines for the
  management of adults with HAP, VAP, and HCAP
  American Thoracic Society, Am J Respir Crit Care
  Med 2005 171388.
• Ventilator circuit change and ventilator-associate
  d pneumonia UpToDate November 16, 2005

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• Thanks for attention!