Population-Based Analysis of Incidence and Mortality of Septic Shock: The Registry of Administrative Data Automatically Recorded-Septic Shock Project

Septic shock is the most severe manifestation of sepsis and remains a leading cause of death and healthcare utilisation. Outcomes vary by patient mix (age, comorbidities), acquisition setting, infection source, and hospital performance, underscoring the need for robust, population-level surveillance to guide policy and care pathways. RADAR-Septic Shock leverages routinely collected administrative data to provide standardised measures of incidence, resource use, and outcomes across an entire regional health system.

The study aims to quantify the population incidence of septic shock and describe patient demographics, comorbidity burden, infection sources, organ failures, and use of life-support therapies; 2) estimate in-hospital and short-term mortality and length of stay; and 3) benchmark hospitals using risk-adjusted observed-to-expected (O/E) mortality to identify variation and inform improvement strategies.

It is a population-based cohort using the Catalan Minimum Basic Data Set for Acute Care Hospitals (CMBD-HA), an audited, mandatory discharge registry covering all acute-care hospitals in the public system. The analytic period spans January 2018-December 2023.

It will include all hospital discharges containing a primary or secondary diagnosis code for septic shock (ICD-10-CM R65.21) or post-procedural septic shock (T81.12XA). This definition prioritises specificity and uniformity across centres. Episodes will be stratified by acquisition setting (community- vs hospital-acquired).

Extracted variables include: demographics (age, sex); comorbidities and morbidity burden (Adjusted Morbidity Groups [GMA] index); infection source; organ failures; advanced life-support interventions (mechanical ventilation, renal replacement therapy, ECMO); ICU admission; length of stay; and mortality.