Severe sepsis and septic shock are the primary causes of multiple organ dysfunction syndrome (MODS), which is the most frequent cause of death in intensive care unit patients. Many water-soluble mediators with pro- and anti-inflammatory action such as TNF, IL-6, IL-8, and IL-10 play a strategic role in septic syndrome. In intensive care medicine, blocking any one mediator has not led to a measurable outcome improvement in patients with sepsis. CRRT is a continuously acting therapy, which removes in a nonselective way pro- and anti-inflammatory mediators; "the peak concentration hypothesis" is the concept of cutting peaks of soluble mediators through continuous hemofiltration. Furthermore, there is evidence of increased efficacy of high-volume hemofiltration compared to conventional CVVH, and other blood purification techniques that utilize large-pore membranes or sorbent plasmafiltration are conceptually interesting.