CRRT efficiency and efficacy in relation to solute size

Removal of blood solutes in patients with decreased or absent glomerular fi ltration is the prime objective of continuous renal replacement therapies ( CRRTs). However, because these blood solutes are of different molecular wei ghts, factors such as the porosity and hydrophobicity of the filter membran es and the extracorporeal flow rates determine the CRRT that is the most ef fective filtration system. This article discusses both small and large solu te removal, the interaction of convection and diffusion, and the potential for CRRTs to remove particular inflammatory mediators of acute renal failur e.