nosocomial pneumonia

1. CURRENT CONCEPTS IN
PREVENTION OF NOSOCOMIAL
PNEUMONIA
DR ANUSHA CM
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3. OUTLINE
• Definitions
• Epidemiology
• Pathophysiology of nosocomial pneumonia
• Microbiology
• Risk factors
• Prevention
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4. • Healthcare-associated infections impose a
significant economic and clinical burden on
the health care systems which is magnified by
increasing infection rates due to MDR
pathogens
• Nosocomial pneumonia : pneumonia acquired
while in hospital
• Derived from Latin word nosocomium:
“hospital”
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5. DEFINATIONS OF NOSOCOMIAL
PNEUMONIA
1. HCAP(Healthcare associated pneumonia)
Pneumonia diagnosed in any patient who was
hospitalised in an acute care hospital for 2 or
more days within 90days of diagnosis ; resided
in a nursing home or long term care facililty;
recived recent intravenous antibiotic therapy ,
chemotherapy or wound care within the past
30 days of the current infection; or attended a
hospital or hemodialysis clinic
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6. 2. HAP ( Hospital acquired pneumonia)
Pneumonia diagnosed 48 hour or more after
hospital administration
3. VAP ( ventilator associated pneumonia)
Pneumonia diagnosed 48 hour or more after
endotracheal intubation
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7. CLINICAL CRITERIA FOR PNEUMONIA
New or progressive lung infiltrate and atleast 2
of the following
1. Hyperthermia / hypothermia
2. Elevated white blood count
3. Purulent tracheal secretions or sputum
4. Worsening of oxygenation
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9. EPIDEMIOLOGY
• Worldwide,occurs at a rate of up to 21 cases per
1,000 hospital admissions
• Numerous studies indicate that VAP occurs in 9 to
27% of all intubated patients
• VAP risk is highest in the course of hospitalisation
and increases over time
• Early onset VAP confers a better prognosis as the
culprit organisms are more sensitive to antibiotics
as opposed to MDR pathogens which are often
responsible for late onset VAP
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10. PATHOGENESIS
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11. PATHOPHYSIOLOGY
• Histologic hallmark of VAP is heterogeneity
• Lesions vary significantly in age and severity
• Dependent areas > non dependent areas
• Oropharyngeal or tracheobronchial
colonization by gram-negative bacilli begins
with the adherence of the microorganisms to
the host’s epithelial cells
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12. ENDOTRACHEAL TUBE
• Ventilated patients are more prone to
repeated micro aspirations around ET cuff and
gain entry into LRT
• Microbiologic, structural and humoral factors
combine to increase the risk of pneumonia in
critically ill patients
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13. STRESS ULCERS
• Critically ill patients are more prone to
develop stress ulcers
• Alterations in gastric pH promotes the growth
of bacteria in sterile environment
• Hence are often treated with H2 antagonists
and PPI
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14. BIOFILM FORMATION
• Biofilm begins to form both inside and outside
the endotracheal tube within a day of
placement and serves as bacterial reservior
within the trachea and oropharynx
• Suctioning or instillation of aerosols through
ET tube can mobilise bacteria from biofilms
into lungs
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16. HEALTHCARE EQUIPMENTS
• Use of contaminated
respiratory equipments,
hospital water system,
transmission of bacteria via
healthcare workers, spread
of microorganisms through
respiratory droplets
,humidifiers and nebulisers
have led to previous
outbreak of Legionella
species and fungal infections
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17. MICROORGANISMS
• Aerobic gram negative bacilli
represent most prevalent
pathogens causing nosocomial
pneumonia
• Enterobacteriaceae which
include Klebsiella, E.coli,
Enterobacter, Citrobacter,
Proteus, Serratia, Pseudomonas,
Acinebacter, Stenotrophmonas
• Among MDR pathogen, MRSA is
most common
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18. RISK FACTORS
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• Mechanical ventilation is the single most
important risk factor for nosocomial pneumonia
increasing risk upto 20 fold.
• Reintubation is also associated with VAP
• Condensate within the ventilator tubing can get
colonised with bacteria and infect LRT
• Risk of VAP is more in COPD and ARDS patients
due to higher colonisation rates
• Aspiration, more so in the presence of
nasogastric tube contributes to higher risk of VAP

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21. DIAGNOSIS
• According to IDSA 2016 guidelines , Noninvasive
sampling with semiquantitative cultures is the
preferred methodology to diagnose VAP
• . For patients with suspected HAP/VAP, we
recommend using clinical criteria alone, rather
than using bronchoalveolar lavage fluid (BALF)
sTREM-1(Soluble Triggering Receptor Expressed
on Myeloid Cells) plus clinical criteria, to decide
whether or not initiate antibiotic therapy
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22. APPROACH TO MANAGEMENT OF
PNEUMONIA
European Respiratory Review 2007 16: 33-
39
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23. • In suspected VAP, coverage for S. aureus,
Pseudomonas aeruginosa, and other gram-
negative bacilli in all empiric regimens is
recommended
• An agent active against methicillinsensitive S.
aureus (MSSA) (and not MRSA) for the empiric
treatment of suspected VAP in patients
without risk factors for antimicrobial
resistance, who are being treated in ICUs
where <10-20% of S aureus isolates are
methicillin resistant is sugggested
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24. • If empiric coverage for MRSA is indicated,
either vancomycin or linezolid is
recommended
• When empiric treatment that includes
coverage for MSSA (and not MRSA) is
indicated, a regimen including piperacillin-
tazobactam, cefepime, levofloxacin,
imipenem, or meropenem is suggested.
Oxacillin, nafcillin, or cefazolin are preferred
agents for treatment of proven MSSA, but are
not necessary for the empiric treatment of
VAP if one of the above agents is used.
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28. PREVENTION
• Selective decontamination of the digestive tract
(SDD) and Selective oropharyngeal
decontamination( SOD) consisted of
oropharyngeal application only of the same
antibioticis designed to prevent bacterial
colonization and lower respiratory tract infection
in mechanically ventilated patients .
• SDD is aimed at preventing oropharyngeal and
gastric colonization with aerobic gram-negative
bacilli and Candida sp. without altering the
anaerobic flora .
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29. PREVENTION
Chances of aspiration can be minimized by
• Placing the patient in a semi recumbent position
• Withholding enteral feeding if the residual
volume in the stomach is large or if bowel sounds
are not heard upon auscultation of the abdomen)
• Using flexible, small-bore enteral tubes
• Placing the enteral tube below the stomach (e.g.,
in the jejunum)
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30. C-A-S-S TUBE
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31. • The primary mechanism for the development
of VAP is through the aspiration of bacteria-
laden subglottic secretions across the ETT cuff
• Semi recumbent position reduces aspiration of
gastric contents (Following tracheal
intubation, mucus flow is reversed in the semi
recumbent position: Possible role in the
pathogenesis of ventilator-associated
pneumonia)
• Raising the head of the bed potentially
increases the hydrostatic pressure exerted
above the ETT cuff by oropharyngeal
secretions, resulting in risk of aspiration.
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32. ROTATION THERAPY
• Normal persons, even during sleep, change their
position approximately every 12 min, which is
minimum physiologic mobility requirement.
• In contrast, critically ill patients are often cared for in
the supine position for extended periods of time.
• In the supine position, the functional residual capacity
is decreased because of alveolar closure in dependent
lung zones. Immobility may impair mucociliary
clearance, with the accumulation of mucus in
dependent lung regions. This can lead to atelectasis
and infection of dependent lung zones.
• As standard practice, patients in the ICU are usually
turned every 2 hours by the nursing staff
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33. ROTATION THERAPY
• Rotational therapy, which includes kinetic
therapy and continuous lateral rotation
therapy (CLRT)
• Kinetic therapy is the continuous turning of a
patient to at least 40 degrees on each side.
The entire kinetic bed frame rotates the
patient from side to side at a speed of about
half a degree per second.
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34. ROTATION THERAPY
• With CLRT, the degree of turn to each side is
less than 40 degrees. The degree of turning
and the length of time the patient spends on
each side are programmable .
• Kinetic beds can provide percussion and
vibration therapy, and they allow for elevation
of the head of the bed
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35. INTERRUPTION OF TRANSMISSION OF
MICROORGANISMS
• Thorough cleaning of instruments before
sterilization or disinfections.
• Sterilize or use high-level disinfection for semi
critical equipment or devices (i.e., items that
come into direct or indirect contact with mucous
membranes of the lower respiratory tract)
• To use sterile (not distilled, unsterile) water for
rinsing reusable semi critical equipment and
devices used on the respiratory tract after they
have been disinfected chemically
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36. RECOMMENDATIONS RATIONALE INTERVENTION QUALITY
EVIDENCE
Special approaches Good evidence that
the intervention
improves the
outcomes but
insufficient data
available on
posssible risks
May lower VAP
rates but insuffient
data to determine
impact on duration
of mechanical
ventilation, length
of stay or mortality
•Selective oral or
digestive
decontamination
•Regular oral care with
chlorhexidine
•Prophylactic probiotics
• Ultrathinpolyurethane
endotracheal tube cuffs
•Automated control of
ET cuff pressure
•Saline instillation
before tracheal
suctioning
•Mechanical tooth
brushing
High
Moderate
Moderate
Low
Low
Low
Low
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37. RECOMMENDATIONS RATIONALE INTERVENTION QUALITY EVIDENCE
Generally not
recommended
No recommendation
Lowers VAP rates
but ample data
suggest no impact
on duration of
mechanical
ventilation, length of
stay or mortality
No impact on VAP
rates or other
patient outcomes,
unclear impact on
costs
Silver coated ET
Kinectic beds
Prone positioning
Closed / in line ET
suctioning
Moderate
Moderate
Moderate
Moderate
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38. PREVENTION BUNDLES
• It is group of intervention related to ventilator
care that, when all intervntions are
simultaneously applied there is enhanced
reduction in incidence of VAP than when each
intervention used seperately
• Measures often include educational
programmes, technical measures ,
survelliance and feedback
• Practical way to enhance care
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39. PREVENTION BUNDLES : EVIDENCE
• Eight practices: Hand hygiene, glove, gown
compliance, elevation of head of the bed, oral
care with chlorhexidine, maintaing an ET cuff
pressure >20cmH20, orogastric rather
nasogastric feeding tubes, avoiding gastric
over distention, and eliminating non essential
tracheal suctioning
• Rate of VAP reduced from 23 to 13 VAP
episodes per 1000 ventilator days
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40. PREVENTION BUNDLES : EVIDENCE
• Five interventions: semi recumbent position,
stress ulcer prophylaxis, DVT prophylaxis,
adjustment of sedation, and daily assesment
for extubation
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41. THANK YOU
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