New Sepsis and Septic Shock Definitions: Clinical Implications and Controversies

New sepsis definitions shift emphasis from the systemic inflammatory response syndrome to organ dysfunction, quantified using the Sequential Organ Failure Assessment (SOFA) score. The new definitions also propose Quick SOFA criteria to rapidly identify potentially infected patients at risk for poor outcomes. The diagnosis of septic shock requires vasopressor dependence and increased lactate levels. Strengths of these definitions include their simplicity and clear association with adverse outcomes. However, their utility in identifying patients with serious infections before frank sepsis ensues remains to be seen. This article reviews challenges in defining sepsis, strengths and weaknesses of the new definitions, and unresolved issues.