Renal replacement therapy


Renal replacement therapy is therapy that replaces the normal blood-filtering function of the kidneys. It is used when the kidneys are not working well, which is called kidney failure and includes acute kidney injury and chronic kidney disease. Renal replacement therapy includes dialysis, hemofiltration, and hemodiafiltration, which are various ways of filtration of blood with or without machines. Renal replacement therapy also includes kidney transplantation, which is the ultimate form of replacement in that the old kidney is replaced by a donor kidney.
These treatments are not truly cures for kidney disease. In the context of chronic kidney disease, they are more accurately viewed as life-extending treatments, although if chronic kidney disease is managed well with dialysis and a compatible graft is found early and is successfully transplanted, the clinical course can be quite favorable, with life expectancy of many years. Likewise, in certain acute illnesses or trauma resulting in acute kidney injury, a person could very well survive for many years, with relatively good kidney function, before needing intervention again, as long as they had good response to dialysis, they got a kidney transplant fairly quickly if needed, their body did not reject the transplanted kidney, and they had no other significant health problems. Early dialysis in acute kidney failure usually brings more favorable outcomes.

Types

Hemodialysis, hemofiltration, and hemodiafiltration can be continuous or intermittent and can use an arteriovenous route or a venovenous route. This results in various types of RRT, as follows: