Systemic Inflammatory Response Syndrome Criteria in Defining Severe Sepsis

The consensus definition of severe sepsis requires suspected or proven infection, organ failure, and signs that meet two or more criteria for the systemic inflammatory response syndrome (SIRS). We aimed to test the sensitivity, face validity, and construct validity of this approach.

We studied data from patients from 172 intensive care units in Australia and New Zealand from 2000 through 2013. We identified patients with infection and organ failure and categorized them according to whether they had signs meeting two or more SIRS criteria (SIRS-positive severe sepsis) or less than two SIRS criteria (SIRS-negative severe sepsis). We compared their characteristics and outcomes and assessed them for the presence of a step increase in the risk of death at a threshold of two SIRS criteria.