Razlučivanje, raščinjavanje, rastvaranje, smrt; gubljenje ili iscrpljivanje snaga; fiz. odvajanje kristaloida od koloida putem osmoze; izmena tečnosti; filol. i ret. v. diereza i asindeton.
ETYM Latin, separation, from Greek, to part asunder, dissolve; dia through + lyein to loose.
Separation of substances in solution my means of their unequal diffusion through semipermeable membranes.
Technique for removing waste products from the blood in chronic or acute kidney failure. There are two main methods, hemodialysis and peritoneal dialysis.
In hemodialysis, the patient’s blood is passed through a pump, where it is separated from sterile dialysis fluid by a semipermeable membrane. This allows any toxic substances which have built up in the bloodstream, and which would normally be filtered out by the kidneys, to diffuse out of the blood into the dialysis fluid. Hemodialysis is very expensive and usually requires the patient to attend a specialized unit.
Peritoneal dialysis uses one of the body’s natural semipermeable membranes for the same purpose. About two liters of dialysis fluid is slowly instilled into the peritoneal cavity of the abdomen, and drained out again, over about two hours. During that time toxins from the blood diffuse into the peritoneal cavity across the peritoneal membrane. The advantage of peritoneal dialysis is that the patient can remain active while the dialysis is proceeding. This is known as continuous ambulatory peritoneal dialysis (CAPD).
In the long term dialysis is expensive and debilitating, and transplants are now the treatment of choice for patients in chronic kidney failure.
Separation of substances in a solution by diffusion through a membrane, especially such separation of waste products from blood in the kidneys.