There are three types of aspiration:

1. Large foreign bodies or food particles
2. Liquid aspiration
3. Bacterial aspiration

Aspiration of solid particles leads to atelectasis and/or recurrent post-obstructive pneumonia. Consequences to liquid aspiration vary depending on the nature of liquid. Acidic stomach contents can lead to diffuse alveolitis and ARDS. Bacterial aspiration leads to lung abscess.

Common predisposing states for aspiration are

• coma
• vomiting
• defective deglutition reflex
• esophageal disease
• drug overdose
• stroke
• post-op state
• seizures
• alcoholism

Children are prone to aspiration.

Diagnosis

Aspiration should be considered if the clinical setting is appropriate in the differential of atelectasis, recurrent pneumonia, ARDS and lung abscess.

Treatment

• Bronchoscopy to remove the foreign body should be considered in patients with atelectasis or recurrent pneumonia.
• ARDS is managed as usual with oxygen, PEEP and ventilators. Large doses of steroids are considered beneficial in the first 24 hours following aspiration.
• Therapy for anaerobic infection should be considered in patients with foul smelling sputum and when the aspiration occurred in a community setting. If the abscess or pneumonia follows aspiration in a hospitalized patient, gram negative coverage should be initiated.