Early Biological and Mechanical Profiling in Sepsis-Associated ARDS

Sepsis-associated acute respiratory distress syndrome (ARDS) is one of the deadliest and most biologically heterogeneous forms of respiratory failure. Despite uniform diagnostic criteria, patients with septic ARDS show wide variability in inflammatory intensity, alveolar epithelial and endothelial injury, alveolar fluid composition, ventilatory mechanical properties, and clinical evolution. Early identification of these differences may enable better prognostication and more precise treatment.

This prospective observational study aims to deeply characterize the earliest phases of septic ARDS by integrating serial bronchoalveolar lavage (BAL) at 0, 24 and 72 hours with parallel plasma biomarker profiling and detailed mechanical ventilation data. This design captures the evolving biological and physiological landscape of septic ARDS during its most dynamic window. The central goal is to identify systemic, alveolar, and hybrid bio-mechano-inflammatory subphenotypes that can inform personalized approaches to support, risk stratification, and future interventional trials.