Aspiration pneumonia in a trauma case
Aspiration pneumonia is defined as a lower respiratory tract infection, due to the aspiration of oral bacterial flora. Trauma patients are at a particular high risk of aspiration pneumonia because they tend to have full stomachs and impaired airway reflexes.
Aspiration pneumonia secondary to trauma is associated with poor outcome, although it is unclear whether this is causation or correlation. The first view is that aspiration is a major preventable factor in the majority of trauma cases2,3. The second view is that aspiration tends to occur in those with severe neurological injury, and these patients are more predisposed to morbidity and mortality4. The corollary of this theory is that patients who were always going to have a poorer outcome will tend to also have aspiration pneumonia.
In one prospective study5, aspiration pneumonia more frequently presented as a bronchopneumonia type pattern with a posterior lung predominance. This is consistent with the case report here demonstrating posterobasal lung collapse.
The management of aspiration pneumonia is with antibiotics. The Australian Antibiotic Therapeutic Guidelines emphasis anaerobic and aerobic sources of infection contributing to aspiration pneumonia. The suggested antibiotic cover is with benzylpenicillin and metronidazole.
Case contributed by A/Prof. Pramit Phal.