Association of septic shock definitions and standardized mortality ratio in a contemporary cohort of critically ill patients.

Purpose: The newly proposed septic shock definition has provoked a substantial controversy in the emergency and critical care communities. We aim to compare new (SEPSIS-III) versus old (SEPSIS-II) definitions for septic shock in a contemporary cohort of critically ill patients. Material and

Methods: Retrospective cohort of consecutive patients, age ≥ 18 years admitted to intensive care units at the Mayo Clinic between January 2009 and October 2015. We compared patients who met old, new, both, or neither definition of sepsis shock. SMR were calculated using APACHE IV predicted mortality.

Results: The initial cohort consisted of 16,720 patients who had suspicion of infection, 7463 required vasopressor support. The median (IQR) age was 65(54-75) years and 4167(55.8%) were male. Compared to patients with old definition, the patients with new definition had higher APACHE III score (median IQR); (73 (57-92) vs. 70 (56-89), p < .01); SOFA score; (6 (4-10) vs. 6 (4-9), p < .01), were older (70 (59-79) vs. 64 (54-74) years, p = .03). They also had higher hospital mortality, N (%) 71, (19.7%) vs. 40 (12.6%), p < .01) and a higher SMR (0.66 vs. 0.45, p < .01).

Conclusions: Compared to SEPSIS-II, SEPSIS-III definition of septic shock identifies patients further along disease trajectory with higher likelihood of poor outcome.