The Impact of the Sepsis-3 Septic Shock Definition on Previously Defined Septic Shock Patients

Objective: The Third International Consensus Definitions Task Force (Sepsis-3) recently recommended changes to the definitions of sepsis. The impact of these changes remains unclear. Our objective was to determine the outcomes of patients meeting Sepsis-3 septic shock criteria versus patients meeting the "old" (1991) criteria of septic shock only. Design: Secondary analysis of two clinical trials of early septic shock resuscitation. Setting: Large academic emergency departments in the United States. Patients: Patients with suspected infection, more than or equal to two systemic inflammatory response syndrome criteria, and systolic blood pressure less than 90 mm Hg after fluid resuscitation. Interventions: Patients were further categorized as Sepsis-3 septic shock if they demonstrated hypotension, received vasopressors, and exhibited a lactate greater than 2 mmol/L. We compared in-hospital mortality in patients who met the old definition only with those who met the Sepsis-3 criteria. Measurements and Main Results: Four hundred seventy patients were included in the present analysis. Two hundred (42.5%) met Sepsis-3 criteria, whereas 270 (57.4%) met only the old definition. Patients meeting Sepsis-3 criteria demonstrated higher severity of illness by Sequential Organ Failure Assessment score (9 vs 5; p < 0.001) and mortality (29% vs 14%; p < 0.001). Subgroup analysis of 127 patients meeting only the old definition demonstrated significant mortality benefit following implementation of a quantitative resuscitation protocol (35% vs 10%; p = 0.006). Conclusion: In this analysis, 57% of patients meeting old definition for septic shock did not meet Sepsis-3 criteria. Although Sepsis-3 criteria identified a group of patients with increased organ failure and higher mortality, those patients who met the old criteria and not Sepsis-3 criteria still demonstrated significant organ failure and 14% mortality rate.