Clinicopathological Correlates of Sepsis-associated Organ Injury in a Tertiary-Care ICU: A Prospective Post-mortem Needle Biopsy Study

This is a prospective post mortem observational study conducted in the Department of Anaesthesiology Pain Medicine and Critical Care at AIIMS New Delhi to study organ level injury patterns in sepsis and septic shock. The study includes adult patients who die in the intensive care unit due to severe sepsis or septic shock as defined by Sepsis 3 criteria and whose relatives provide written informed consent. Ultrasound guided post mortem core needle biopsies will be performed within six hours of death from liver lung and kidney using sterile technique. Two to three cores per organ will be fixed in 10 percent neutral buffered formalin processed into paraffin blocks and examined by experienced pathologists blinded to clinical data. Routine stains and organ specific special stains will be used to identify characteristic morphological changes. The primary outcome is to describe the spectrum of histopathological lesions in these organs among patients dying of septic shock. Secondary objectives include correlation of histopathology severity with ante mortem organ dysfunction grading of parenchymal and epithelial injury and identification of immune cell infiltration patterns. Exploratory analysis subject to resources will include immunohistochemistry for selected markers of cell death endothelial injury complement activation regeneration and immune exhaustion such as cleaved caspase 3 complement C5b 9 syndecan 1 RIPK1 ki67 and PD1. Findings will be correlated with clinical and laboratory parameters to improve understanding of sepsis related multi organ injury and provide a tissue level framework for future translational biomarker research in critical illness.