Aspiration usually occurs in patients who :

- Have a depressed level of consciousness.

- Have dysphagia resulting from neurologic or esophageal disorders.

- Have an endotracheal (nasotracheal or orotracheal), tracheostomal, or enteral (nasogastric or orogastric) tube in place.

- and/or are receiving enteral feeding .

Although prevention of pneumonia in such patients may be difficult, methods that make regurgitation less likely (e.g., placing the patient in a semirecumbent position {i.e., by elevating the head of the bed} may be beneficial .