Hemodialysis is the artificial blood filtration made by specific machines in substitution of the kidneys. Hemodialysis may be necessary in patients suffering from diseases that cause renal failure, like diabetic renal complications, lupic renal complications and others. During hemodialysis the blood of the patient is deviated to the filtering machine and after the filtration it returns to the body. Hemodialysis is generally done two, three or more times a week in a process that takes several hours. Sometimes kidney transplantation is an alternative to hemodialysis.