Prognostic Accuracy of qSOFA Score, SIRS Criteria, and EWSs for In-hospital Mortality Among Adult Patients Presenting With Suspected Infection to the Emergency Department (PASSEM): Protocol for an International Multicentre Prospective External Validation Cohort Study

Over the past decade, medical advances in sepsis continued to focus on sepsis as a prevalent condition that accounts for 10% of admissions to intensive care units (ICUs) and is associated with a 10-20% in-hospital mortality rate. Standardised protocols and physician awareness have significantly improved survival, but mortality rates remain between 20% and 36%, with ~270,000 deaths annually in the United States. However, of patients with sepsis, 80% are treated in an emergency department (ED), and the remainder develops sepsis during hospitalisation with other conditions. In 2016, the Society of Critical Care Medicine/European Society of Intensive Care Medicine (SCCM/ESICM) task force redefined sepsis based on organ dysfunction and mortality prediction. Sepsis now is defined as life-threatening organ dysfunction caused by dysregulated host response to infection. This definition emphasises the complexity of the disease that cannot be explained by infection or body response to it. Acute change in Sequential Organ Failure Assessment (SOFA) score ≥2 indicates sepsis-related organ dysfunction, a predictor of excess in-hospital mortality. Systemic Inflammatory Response Syndrome (SIRS) and "severe sepsis" terms were omitted from the most recent definition. SIRS has been criticised for its poor specificity, while "severe sepsis" may underestimate sepsis's seriousness. A subset of patients may develop septic shock with underlying profound organ dysfunction and excess mortality. Clinically, septic shock is defined as persistent hypotension requiring vasopressors to maintain mean arterial pressure (MAP) ≥ 65 mm Hg and serum lactate level ≥ 2 mmol/L (18 mg/dL) despite adequate volume resuscitation. Early identification of a patient with infection who may develop sepsis is of utmost importance. Unfortunately, this remains elusive because no single clinical measure or test can reflect complex pathophysiological changes in patients with sepsis. However, multiple clinical and laboratory parameters indicate impending sepsis and organ dysfunction. Screening tools using these parameters can help identify the condition, such as SIRS, quick SOFA (qSOFA), National Early Warning Score (NEWS), or Modified Early Warning Score (MEWS). The 2016 SCCM/ESICM task force recommended using qSOFA, while the 2021 Surviving Sepsis Campaign strongly recommended against its use compared with SIRS, NEWS, or MEWS as a single screening tool for sepsis or septic shock. We hypothesised that qSOFA has greater prognostic accuracy than SIRS and EWS (NEWS/NEWS2/MEWS).