Association of oXiris Hemoadsorption with Inflammatory, Hemodynamic, Respiratory, and Organ Dysfunction Parameters in Patients with Sepsis and Septic Shock in the Intensive Care Unit: A Retrospective Comparative Cohort Study

Background/Objectives: This study aimed to evaluate the associations of adding oXiris hemoadsorption therapy to standard sepsis treatment with inflammatory markers, organ dysfunction, hemodynamic parameters, respiratory function, and overall survival (OS) in patients with sepsis and septic shock managed in the intensive care unit (ICU). In our ICU, oXiris was used as adjunctive hemoadsorption for endotoxin and cytokine removal, delivered on a continuous venovenous hemodiafiltration (CVVHDF) platform and initiated independently of acute kidney injury (AKI). Methods: This retrospective comparative cohort study included 83 adult patients with sepsis or septic shock admitted to the Internal Medicine ICU. Patients were allocated to either the oXiris group (n = 33), which received oXiris hemoadsorption for 72 h in addition to standard sepsis therapy, or the control group (n = 50), which received standard sepsis therapy without oXiris or another adsorptive CRRT membrane. Conventional intermittent hemodialysis for independent renal indications was permitted and recorded in both groups. C-reactive protein (CRP), procalcitonin (PCT), white blood cell count, updated Sequential Organ Failure Assessment (SOFA-2) score, PaO2/FiO2 ratio, serum lactate, norepinephrine dose, and renal parameters were recorded at baseline, 48 h, and 72 h. Between-group differences in temporal changes were evaluated using adjusted generalized estimating equation models, and robustness was assessed with a propensity-score-based inverse-probability-of-treatment-weighted (IPTW) sensitivity analysis. Survival analysis was performed using the Kaplan–Meier method and log-rank test. Results: The oXiris group had significantly greater baseline clinical severity, including a higher burden of renal dysfunction. This marked baseline imbalance was considered important when interpreting the unadjusted findings and supported the use of adjusted and IPTW analyses. In the oXiris group, CRP, PCT, SOFA-2 score, and norepinephrine requirement showed greater reductions over time, whereas the PaO2/FiO2 ratio improved significantly. After IPTW adjustment, the between-group differences in SOFA-2 score, norepinephrine requirement, and PaO2/FiO2 ratio remained statistically significant, whereas the CRP and PCT differences were no longer statistically significant. Serum lactate levels showed an increasing trend in the oXiris group compared with the control group (p = 0.042). No significant difference in overall survival was observed between the two groups (p = 0.897). Conclusions: The addition of oXiris hemoadsorption to standard sepsis therapy was associated with favorable early temporal changes in organ dysfunction, norepinephrine requirement, and oxygenation. However, the observed CRP and PCT differences were not preserved after IPTW adjustment, and no survival association was identified. These findings should therefore be interpreted as associations rather than evidence of a causal treatment effect.