Blood purification therapy for severe sepsis: a multicenter, observational cohort study in northern Japan

Background: Sepsis is associated with life-threatening organ dysfunction caused by a dysregulated host response to infection. However, no specific therapy has been shown to improve mortality in patients with sepsis. We conducted a study to clarify the utilization status of various BPTs and the clinical characteristics of patients who received BPTs in northern Japan. In addition, the association of various BPTs with clinical outcomes was examined. Methods: This is a sub-analysis of the Tohoku Sepsis Registry, a multicenter, prospective, observational cohort study. To determine whether BPT was independently associated with in-hospital mortality in patients with severe sepsis, the following analyses were performed. Differences between survivors and non-survivors were assessed using Wilcoxon rank sum tests for continuous variables and Chi-square tests for categorical variables. Univariate logistic regression analysis was used to evaluate the factors associated with in-hospital mortality. In the multivariate logistic regression analysis, adjustments were made for the variables that were significant in the univariate logistic regression analysis. Clinical factors associated with mortality were analyzed. Results: We enrolled 616 consecutive patients (≥ 18 years) with median Sequential Organ Failure Assessment scores of 8.0. During median of 22 days hospitalization, 139 patients died (mortality 22.6%). 20.7% of patients with severe sepsis received any type of BPT (mortality 38.6%). BPT consisted of 65.1% continuous renal replacement therapy (CRRT) with renal indication (mortality 48.8%), 26.0% CRRT with non-renal indication (mortality 21.2%), 22.2% intermittent renal replacement therapy (mortality 32.1%), and 33.1% polymyxin B-immobilized fiber column-direct hemoperfusion (mortality 42.9%). Meanwhile, no BPT group (mortality 18.5%) showed a significantly lower mortality than any BPT group. Besides, in multivariate analyses, all BPT modes were not independently associated with all-cause mortality. Conclusions: This study suggested the clinical status of BPTs for severe sepsis patients in northern Japan. Among all types of BPT, continuous renal replacement therapy (CRRT) for renal indication was most frequently selected. Severe sepsis patients received BPT had a higher mortality and severity; however, the BPT implementation may not be associated with mortality. Trial registration UMIN-CTR, UMIN000010297, Registered on 22 March 2013, https://upload.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000012055).