Using the Pneumonia Severity Index to guide outpatient treatment

March 1, 2007

The Pneumonia Severity Index (PSI), which categorizes patients into 5 groups according to risk of short-term mortality, is used at some centers to determine which patients with community-acquired pneumonia can be safely treated as outpatients. Is this a reasonable practice? Yes, according to a multicenter study conducted in France, which found that use of the PSI in emergency departments (EDs) is associated with a greater likelihood of low-risk patients being treated as outpatients, without compromising patient safety.

The Pneumonia Severity Index (PSI), which categorizes patients into 5 groups according to risk of short-term mortality, is used at some centers to determine which patients with community-acquired pneumonia can be safely treated as outpatients. Is this a reasonable practice? Yes, according to a multicenter study conducted in France, which found that use of the PSI in emergency departments (EDs) is associated with a greater likelihood of low-risk patients being treated as outpatients, without compromising patient safety.

The study included 925 patients (median age, 71 years) with pneumonia from 8 EDs. The PSI was used in 51% of the patients. About 49% of all patients were considered to be at low risk.

About 43% of the low-risk patients in the PSI group were treat- ed as outpatients, compared with about 24% of those in the non-PSI group. A multivariate analysis indicated that the likelihood of receiving outpatient treatment was increased among patients in the PSI group who were in risk class I or II (low risk).

The analysis also found that after adjusting for pneumonia severity, the mortality rate was lower in the PSI group.