Infectious Diseases I
About 90% of hospital-acquired pneumonia episodes in critically ill patients occur during MV. MV is
an independent risk factor for pneumonia.
The incidence of pneumonia increases with the duration of mechanical ventilation, with the highest risk
during the first 5 days. Individual risk factors for VAP include underlying chronic lung disease, acute
lung injury, aspiration, coma, trauma (e.g., chest trauma; traumatic brain injury), burns, reintubation,
and overall severity of illness.
VAP accounts for more than 50% of antibiotic use in critically ill patients and has an attributable cost
of more than $40,000 per episode.
VAP has an estimated all-cause mortality of 20%β50%, which varies among critically ill populations.
VAP has an attributable mortality of about 13%, as seen in a recent meta-analysis.
VAP is a distinct type of hospital-acquired pneumonia that occurs more than 48 hours after endotracheal
intubation. VAP is further classified by the Centers for Disease Control and Prevention (CDC) as a
ventilator-associated event and infection-related ventilator-associated complication. Updated guidelines
from the IDSA for the diagnosis and management of VAP were published in 2016. (Please see Table 2
at the end of this section for summary and comparison with 2005 guidelines.)
caused by viral or fungal pathogens.
The prevalence of specific bacterial pathogens varies between critically ill patient populations,
geographic region, and local antibiotic usage patterns. Risk factors for multidrug-resistant organisms
(MDROs) are summarized in Box 1.
Classification of VAP as early onset (within the first 2β4 days of hospitalization) or late onset (after 5
days or more of hospitalization) to differentiate between suspected pathogens is no longer recommended.
However, longer duration (e.g., 5 days) of hospitalization before the onset of VAP is associated with
nosocomial and MDRO pathogens.
Box 1. Risk Factors for MDROs Causing VAP
Prior intravenous antibiotic therapy in preceding 90 days
Acute renal replacement therapy before VAP onset
5 or more days of hospitalization before the occurrence of VAP
Septic shock at the time of VAP
ARDS preceding VAP
MDRO = multidrug-resistant organism.
VAP is considered a reportable and preventable complication of endotracheal intubation and mechanical
ventilation.
Recommended essential practices for preventing VAP include (Infect Control Hosp Epidemiol 2022;
43:687-713):
Avoid intubation and prevent reintubation if possible.
Minimize sedation of ventilated patients whenever possible.