Polymyxin B immobilized column is effective for hydrochloric acid-induced lung injury in rats

The purpose of this study was to examine whether hemoperfusion using polymyxin B (PMX) immobilized column improves hydrochloric acid (HCl)-induced lung injury. Rats weighing 350 g underwent hemoperfusion for 30 min at a flow rate of 120 ml/h after the intratracheal instillation of hydrochloric acid or water. Rats were divided into those that underwent hemoperfusion, with or without polymyxin B column, 30 min after HCl instillation ("HCl+PMX" and "HCl"), and hemoperfusion with or without polymyxin B column 30 min after water instillation ("Aqua+PMX" and "Aqua"). Systolic blood pressure, arterial blood gas analysis and white blood cell count and neutrophils were measured before, 1 and 3h after hemoperfusion. Plasma and bronchoalveolar lavage fluid concentrations of growth-related oncogene/cytokine-induced neutrophils chemoattractant-1 (GRO/CINC-1) were measured at 1 and 3h after hemoperfusion. Arterial oxygen concentrations were higher in the "HCl+PMX" group than in the "HCl" group. The total numbers of cells and neutrophils in the bronchoalveolar lavage fluid were significantly higher in the "HCl" group than in the others. The GRO/CINC-1 concentrations in the plasma and bronchoalveolar lavage fluid and the albumin ratio in the "HCl+PMX" group were significantly lower than in the "HCl" group. Direct hemoperfusion using polymyxin B immobilized column treatment affects the recruitment of circulating neutrophils to the lungs due to the decrease in mediators for non-endotoxic lung injury.