Blood purification for critical care medicine: endotoxin adsorption

Many kinds of blood purifying technologies have been applied to the treatment of critically ill patients since 1979 when plasma exchange with hollow-fiber membranes was developed. These technologies have been applied not only to the removal of toxic substances, but also to the treatment of objective diseases and the removal of the factors relating to the associated inflammation. This article summarizes these methods and their efficacies for critically ill patients, especially those with severe sepsis. Attempts have been made to remove endotoxin, the main cause of sepsis, from the circulation using polymyxin B immobilized fiber, charcoal hemoperfusion, and plasma or whole blood exchange. Attempts have also been made to remove proinflammatory cytokines, eicosanoides, and coagulative factors from the circulation in the human body. Continuous hemofiltration or hemodiafiltration is the representative technology. The efficacy of these methods has been established, but several issues remain unresolved. All methods of the treatment of severe sepsis are discussed with reference to treatment indications, efficacy, and outcome parameters. In particular, the clinical results of endotoxin removal with polymyxin B immobilized fiber are summarized in this article.