ICU admission and severity assessment in community-acquired pneumonia

The past 15 years have seen major advances in our understanding of severity assessment in community-acquired pneumonia (CAP). Prognostic tools have been promoted to guide all major management decisions in CAP, including admission to the critical care unit. Several recent studies, including the study by Renaud and colleagues, have challenged us to re-evaluate how we consider severe CAP, a concept for which there is still no universally accepted definition. Existing severity scores such as the Pneumonia Severity Index and the CURB65 score are designed to predict 30-day mortality. As a result, they are heavily weighted by age and co-morbidity. They perform less well when predicting other outcomes such as requirement for ICU admission and are of limited use in the critical care environment. This commentary discusses recent attempts to develop useful severity criteria to guide the use of ICU resources in patients with severe CAP.