Hemoperfusion with an immobilized polymyxin B fiber column improves tissue oxygen metabolism

Recently, direct hemoperfusion with a polymyxin B-coated fiber column (DHP-PMX) has been increasingly used for the treatment of sepsis, and an improvement in outcomes has been reported. However, the mechanism of the method is not known in detail. In the present study, we examined whether the performance of DHP-PMX improved tissue oxygen metabolism in patients with sepsis. Twenty-two patients with sepsis, satisfying the following criteria, were enrolled in the study: (i) signs of systemic inflammatory response syndrome caused by infection; and (ii) mean arterial blood pressure > or =60 mm Hg (irrespective of the use of catecholamines). A thermodilution catheter was inserted prior to DHP-PMX for appropriate intravenous infusion, and the DHP-PMX was carried out twice within 24 h (for 3 h each time). Then, the gastric mucosal-arterial PCO(2) difference (PCO(2) gap) was calculated as the gastric mucosal PCO(2) minus arterial PCO(2). A PCO(2) gap > or =8 mm Hg was used to define abnormal tissue oxygen metabolism. PCO(2) gap was measured before PMX-DHP, as well as 24, 48, and 72 h afterward. PCO(2) gap was 20 +/- 4.9 mm Hg before DHP-PMX vs. 16 +/- 2.7 mm Hg (P = 0.189) at 24 h, 12 +/- 2.8 mm Hg (P = 0.046) at 48 h, and 11 +/- 2.2 mm Hg (P = 0.045) at 72 h afterward, showing a significant decrease from 48 h onward compared with before treatment. These findings suggest that DHP-PMX improves tissue oxygen metabolism.