DIALYSIS

TYPES:
The two main types of dialysis,
Hemodiaolysis and peritoneal dialysis,remove waste and excess water from the blood in different ways.
Hemodialysis removes waste and water by circulating blood outside the body through an
external filter,called a dialyzer,that contains a semi-permeable membrane.
The blood flows in one direction and the dialysate flows in the opposite.
The counter current flow of the blood and dialysate maximises the concentration gradient of
solutes between the blood and dialysate,which helps to remove more urea and creatinine from the blood.
The concentration,on of the solutes such as(potassium,phosphorus)are undesirably high in the blood,but low or absent in dialysate solution  and constant replacement of the dialysate ensures that the concentration of undesired solutes is kept low on this side of the membrane

The dialysate  solution has levels of minerals like  potassium and calcium that are similar to their
natural concentration in healthy blood.For another solute,

Bicarbonate,dialysis solution level is set at a slightly higher level than in normal blood,to encourage diffusion of bicarbonate in to the blood.