Epidemiology of sepsis and septic shock in intensive care units between sepsis-2 and sepsis-3 populations: sepsis prognostication in intensive care unit and emergency room (SPICE-ICU)

BACKGROUND: Diagnosing sepsis remains difficult because it is not a single disease but a syndrome with various pathogen- and host factor-associated symptoms. Sepsis-3 was established to improve risk stratification among patients with infection based on organ failures, but it has been still controversial compared with previous definitions. Therefore, we aimed to describe characteristics of patients who met sepsis-2 (severe sepsis) and sepsis-3 definitions. METHODS: This was a multicenter, prospective cohort study conducted by 22 intensive care units (ICUs) in Japan. Adult patients (≥ 16 years) with newly suspected infection from December 2017 to May 2018 were included. Those without infection at final diagnosis were excluded. Patient’s characteristics and outcomes were described according to whether they met each definition or not. RESULTS: In total, 618 patients with suspected infection were admitted to 22 ICUs during the study, of whom 530 (85.8%) met the sepsis-2 definition and 569 (92.1%) met the sepsis-3 definition. The two groups comprised different individuals, and 501 (81.1%) patients met both definitions. In-hospital mortality of study population was 19.1%. In-hospital mortality among patients with sepsis-2 and sepsis-3 patients was comparable (21.7% and 19.8%, respectively). Patients exclusively identified with sepsis-2 or sepsis-3 had a lower mortality (17.2% vs. 4.4%, respectively). No patients died if they did not meet any definitions. Patients who met sepsis-3 shock definition had higher in-hospital mortality than those who met sepsis-2 shock definition. CONCLUSIONS: Most patients with infection admitted to ICU meet sepsis-2 and sepsis-3 criteria. However, in-hospital mortality did not occur if patients did not meet any criteria. Better criteria might be developed by better selection and combination of elements in both definitions. TRIAL REGISTRATION: UMIN000027452