Identifying patients at risk for severe CAP: A model for the ED

June 1, 2007

A number of prediction models have been developed to identify patients with community-acquired pneumonia (CAP) who are at increased risk for severe illness. España and associates have developed a relatively simple model that can be used in the emergency department (ED), and they report that it compares favorably with other prediction models, such as those developed by the American Thoracic Society (ATS) and the British Thoracic Society (BTS).

A number of prediction models have been developed to identify patients with community-acquired pneumonia (CAP) who are at increased risk for severe illness. España and associates have developed a relatively simple model that can be used in the emergency department (ED), and they report that it compares favorably with other prediction models, such as those developed by the American Thoracic Society (ATS) and the British Thoracic Society (BTS).

They developed their clinical prediction rule based on data from 1057 patients presenting to an ED. The prediction rule was validated in 2 populations: 719 patients from the same center and 1121 patients from 4 other hospitals. Multivariate analysis identified 8 independent predictors of severe CAP: arterial pH less than 7.3, systolic blood pressure less than 90 mm Hg, respiration rate greater than 30 breaths per minute, altered mental status, blood urea nitrogen level greater than 30 mg/dL, arterial oxygen tension less than 54 mm Hg or ratio of arterial oxygen tension to fraction of inspired oxygen less than 250 mm Hg, age 80 years or older, and multilobar/bilateral lung involvement.

The authors found that their clinical prediction model was better at identifying patients at risk for severe CAP than the modified ATS rule, the BTS CURB-65, or the Pneumonia Severity Index.