Effect of oXiris-CVVH on the Clinical Outcomes of Patients with Septic Shock: An Inverse Probability of Treatment-Weighted Analysis

Abstract

Background: Limited previous studies had proved that oXiris-continuous veno-venous hemofiltration (CVVH) could decrease endotoxins and inflammatory factors, thereby improving circulation’s stability. However, conclusive data are lacking regarding the comparison between oXiris membrane (with the function of removing endotoxins and decreasing inflammatory factors) and AN69 filters (with the only function of decreasing inflammatory) on the mortality of patients with septic shock. The potential mechanisms of oXiris that might influence the mortality of septic shock patients remain unexplored. Methods: This is a single-center, retrospective cohort study. The experimental group (30 patients with septic shock) was treated with oXiris-CVVH, and the control group (46 patients with septic shock) was treated with AN69 filter-CVVH. We employed the inverse probability of treatment-weighting method (IPTW), doubly robust estimation, and mediating effect analysis to analyze those clinical outcomes, with a special focus on the results of 28-day mortality, 72-h lactate, the need for norepinephrine (NE) in the next 72 h. Results: A total of 76 patients with septic shock who received blood purification therapies were enrolled. After IPTW, differences in patient characteristics have been minimized. The 28-day mortality in the control group is higher than in the treatment group (73.3% vs. 47.3%, p < 0.001; median survival time: 10 vs. ≥28 days, log-rank p = 0.0366). And the 25% decrease and the 50% decrease in demand for NE in the next 72 h are different between the treatment and control groups (median time of 25% decrease in demand: 24 vs. >72 h, log-rank p = 0.0126; median time of 50% decrease in demand: 24 vs. >72 h, log-rank p = 0.0322). The 72-h lactic acid level and white blood cell (WBC) counts in the oXiris group are lower than in the control group. The 72-h lactate fully mediated the effects of oXiris on 28-day mortality after confounds adjustment. Conclusions: For septic shock patients, the use of oXiris-CVVH was associated with lower mortality and appeared to reduce lactate, NE dosage, PCT, and WBC counts, as compared to AN69-CVVH.