Polymyxin B Hemoperfusion Improves Hemodynamic Status in Patients with Sepsis with Both Gram-Negative and Non-Gram-Negative Bacteria

Background: Direct hemoperfusion with a polymyxin B (PMX) often produces improvement in patients with sepsis caused by bacteria other than those classified as gramnegative. The aim of the present study is to clarify the therapeutic effects of PMX in patients with sepsis caused by bacteria other than gram-negative bacteria. Methods and Findings: We enrolled 41 patients with severe sepsis including various other diseases, which were treated with PMX. We evaluated the improvement in blood pressure, vasopressor requirement, respiratory condition, Sequential Organ Failure Assessment (SOFA), inotropic score, and serum biochemical markers before and after PMX therapy. PMX therapy improved inotropic scores (14.3 to 8.4, p0.01) and small decrease partial SOFA scores (2.8 to 2.1, p0.01). We compared hemodynamic scores between patients with gram-negative bacteria (GN group) and nongram-negative bacteria (non-GN group). Changes in blood pressure, inotropic score and partial SOFA scores by PMX therapy showed no significant differences between the GN and non-GN groups (p = 0.26, p = 0.11 and p = 0.3, respectively). Furthermore, we compared the 28-day mortality between GN and non-GN groups. As a result, there is no significant deference. (p = 0.85). Conclusion: PMX therapy is effective to improve hemodynamic status of septic patients not only with gramnegative but with non-gram-negative bacteria. Main limitation is that the sample size was relatively small and the study was performed in a single center.