What does hemodialysis mean?
Hemodialysis is a medical treatment used primarily for people with severe kidney failure. Blood is circulated through a machine containing a semipermeable membrane, which removes waste products, excess salts, and fluid before the filtered blood returns to the body. The process also helps correct electrolyte and acid-base imbalances, but it does not cure the underlying kidney disease or restore normal kidney function. Patients commonly undergo hemodialysis several times a week in a clinic or hospital setting. The term distinguishes blood-based dialysis from peritoneal dialysis, which uses the lining of the abdomen as a filtering membrane. Although "dialysis" is often used informally to mean hemodialysis, the more precise term is valuable in medical contexts because different dialysis methods involve different procedures, equipment, risks, and care requirements.
nounA method of treating severe kidney failure in which a patient's blood is circulated through a filtering machine, removing waste products and excess fluid before the blood is returned to the body. It is also called renal or extracorporeal dialysis.
- The process of removing waste products and excess fluid from the blood by passing it through a filtering machine outside the body, usually as treatment for severe kidney failure.
"The patient receives hemodialysis three times a week at the renal unit."
"Her kidney function deteriorated, and she began hemodialysis while awaiting a transplant."
"Hemodialysis removes waste and excess fluid from the blood but does not cure the underlying kidney disease."
The plural is grammatically possible but uncommon because hemodialysis is usually discussed as a treatment or process.
"The study compared outcomes for patients receiving different types of hemodialyses."
Hemodialysis can act as a substitute for failed kidneys, filtering waste and balancing the blood's chemistry several times a week.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Where does hemodialysis come from?
Hemodialysis combines the Greek roots hēma, meaning "blood," and dialusis, meaning "separating" or "distinguishing." The second element comes from dialyzein, "to separate," and appears in related forms such as dialysis and analysis. Hemodialysis belongs to the medical vocabulary developed as machines capable of mechanically filtering blood became established treatments for severe kidney failure.
How hemodialysis is actually used
Hemodialysis is a formal medical term. In general use, "dialysis" often refers specifically to this procedure, although medically it can also include other forms of dialysis.
Easily confused with hemodialysis
Hemodialysis filters waste from blood outside the body, whereas hemolysis is the rupture of red blood cells and the release of their contents into the bloodstream.