Why the blood flows through many small channels in the dialysis unit, rather than through a single large channel?
Answers
Dialysis is the major treatment for kidney failure. It is the medical word for filtering waste products and removing fluid from your body that your kidneys are no longer able to remove.
There are two forms of dialysis: Haemodialysis andPeritoneal Dialysis There are two forms of dialysis: Haemodialysis andPeritoneal Dialysis
Haemodialysis
Haemodialysis is a process by which excess waste products and water are removed from the blood by using a dialyser, also known as an artificial kidney. This form of treatment means the blood is transported outside the body through the dialyser via a specially created vein in the forearm known as arterio-venous fistula. This process requires the use of a machine.
In haemodialysis, the blood channels through tubing to the dialyser. The dialyser is a bundle of hollow fibres made up from a semi-permeable membrane. The membrane is thin film with thousands of microscopically small holes. The holes allow water and small dissolved substances to pass through but retain the proteins and blood cells, which are too large.
During the dialysis treatment the blood is allowed to flow on one side of the membrane and dialysate solution on the other, and exchange (diffusion) takes place from the blood to the dialysate solution and visa-versa. The dialysate solution has a salt composition similar to blood but without the waste products. Usually one session takes about 4 hours.