Hemodialyzer performance: biological indices

In the last decade there has been a rapid increase in the number of biological indices that could potentially be used as measures of hemodialyzer or membrane biocompatibility. Consequently, it has become more challenging for all of those involved in renal replacement therapy to evaluate the relative merits of one membrane versus another when faced with their ever increasing variety of parameters. This review attempts to summarize the current array of biological parameters described in the literature as indices of biocompatibility and provide a critique of their utility. Emphasis is placed on measures of activation of the plasma cascade systems, complement, coagulation, and kinin as primary indices of biocompatibility. Additional information on neutrophil, monocyte, platelet, lymphocyte and natural killer (NK) cell effects may provide further insight into blood-membrane mediated interactions although many of these may parallel plasma cascade systems activation. The importance of good statistical design and analysis is emphasized to ensure meaningful interpretation of any study.