Preventing Hospital Acquired Pneumonia

Hospital acquired pneumonia (HAP), or nosocomial pneumonia is an acute lower respiratory tract infection that is acquired after 48 hours of admission to hospital and is not present at the time of admission. Diagnosis requires new symptoms of pneumonia (See table 2) with new radiographical features on chest imaging. HAP can be defined as early or late onset, with diagnosis in the first 4 days of admission being labelled ‘early’, and anything afterward being ‘late’. Early onset HAP is typically associated with similar microorganisms as community acquired pneumonia (Streptococcus pneumoniae, Haemophilus Influenzae, Influenza A, Mycoplasma Pneumoniae). Late onset HAP is most frequently caused by microorganisms present in the hospital environment including Pseudomonas, methicillin resistant Staphylococcus aureus (MRSA) and other Gram-negative bacteria. This is also true for patients who develop ventilator-associated pneumonia (VAP) within the intensive care unit.