Hemodialysis allows people with kidney failure to survive vital organ failure; however, most do not recover premorbid functional status. Despite early efforts focused on increased removal of small molecular weight solutes, high levels of morbidity and mortality persist due to the condition underlying kidney failure, co-morbid medical conditions, and poor clearance of larger molecules. Early studies demonstrated that hemodiafiltration (HDF) increases removal of larger molecules through convective clearance.