and aspiration are implemented. These measures are based on avoiding or improving the
specific risk factors identified to promote VAP in studies involving multivariate analysis.
The recently published SHEA/IDSA practice recommendation on “Strategies to Prevent
Ventilator-Associated Pneumonia in Acute Care Hospitals” is a compendium of recommen-
dations sponsored in partnership with the Association for Professionals in Infection Control
and Epidemiology (APIC), the Joint Commission, and the American Hospital Association
(AHA) (Table 3).
The core recommendations are designed to interrupt the three most common
mechanisms whereby VAP develops: aspiration of secretions, colonization of the aerodigestive
tract, and use of contaminated equipment.
Key components are (i) ensuring staff education and infection surveillance, (ii)preventing
the transmission of microorganisms, and (iii) modifying host risk factors for infection. When
fully implemented, guidelines to prevent VAP have been shown to improve patient outcomes
and are cost effective (117–121).
Effective infection-control measures, hand hygiene, and patient isolation to reduce cross-
infections are routine mandatory practices (2,33,96,112,122). Recommended practices are the
surveillance of ICU infections to identify and quantify endemic and new MDR pathogens and
the acquiring of recent data on which to base infection monitoring and antimicrobial therapy in
patients with suspected HAP or other nosocomial infection (2,32,33,78,96,112,122–125).
The time of invasive ventilatory support and, therefore, the risk of VAP can be reduced
by noninvasive ventilatory support (126) and protocol-driven weaning (127). Reintubation also
increases the risk of VAP (2,27,33,34,110,128–130).
In high-risk populations, early tracheostomy in patients predicted to require prolonged
mechanical ventilation has been proposed as a preventive strategy and shown to reduce the
incidence of VAP (131).
The use of orotracheal intubation and orogastric tubes rather than nasotracheal
intubation and nasogastric tubes has been reported to prevent nosocomial sinusitis and to
reduce the risk or VAP, although a direct link has not been demonstrated (2,33,34,94,112,132).
Good oral hygiene can reduce the load of infective microorganisms in the oropharynx
and can be a cost-effective way of preventing VAP (133). The use of oral chlorhexidine has
served to avoid ICU-acquired HAP, and at present, the SHEA/IDSA recommendation is to
undertake regular oral care with an antiseptic solution (134–139). The optimal frequency for
oral care remains unresolved.
Table 2 Risk Factors for Nosocomial Pneumonia and VAP
Category
Unventilated or wide range
of hospital patients Mechanically ventilated patientsHost related Advanced age, severe illness, trauma/
head injury, poor nutritional status,
coma, impaired airway reflexes,
neuromuscular disease
Advanced age, chronic lung disease,
severe illness, reduced
consciousness or coma, organ
failure, severe head trauma, shock,
blunt trauma, burns, stress ulceration
Device related Endotracheal intubation, nasogastric
tube, bronchoscopy
Prolonged mechanical ventilation,
reintubation or self-extubation,
ventilator circuit changes at intervals
<48 hr, emergent intubation after
trauma, PEEP, tracheostomy
Drug related Immunosuppression therapy Prior antimicrobial therapy, antacid or
H 2 blocker therapy, barbiturate
therapy after head trauma
Miscellaneous Thoracic or upper abdominal surgery,
prolonged surgery, prolonged
hospitalization, large-volume
aspiration
Thoracic or upper abdominal surgery;
gross aspiration of gastric contents,
supine head position, fall-winter
seasonAbbreviations:H2,histamine type 2; PEEP, positive end-expiratory pressure.
Source: Data obtained from Refs. 2,12,18,26,32–34,67,82,83,87–114.
Nosocomial Pneumonia in Critical Care 183