Aspiration pneumonia: incidence, mortality, and at-risk populations.

Pulmonary aspiration in the hospitalized patient can be devastating. Most aspiration events occur in patients with a swallowing disorder. Aspiration can be divided into 3 separate etiologies: oropharyngeal bacteria, particulate matter, and acidified gastric contents. Reported prevalence data are extremely variable, ranging from 10% to 70%. Mortality is related to the volume and content of the aspirate and is reported to be as high as 70%. Neurologic dysfunction, decreased consciousness, advancing age, gastroesophageal reflux, and tube feeding are all potential risk factors for the development of aspiration.