[Transport processes--ultrafiltration in peritoneal dialysis].

In patients with terminal renal failure treated by peritoneal dialysis diffusion and ultrafiltration are used for removal of substances from the blood. Neofiltration is realized via the osmolar gradient, determined by different concentration of glucose and dialysis solutions. Osmotic water transport during peritoneal dialysis is limited. In the course of one exchange of two liters of the dialysate, exponential reduction of glucose levels in the peritoneal fluid ensues against time. Substance of low molecular weight, such as glucose, are resorbed from dialysate reducing the osmotic gradient between blood and dialysis fluid. Two successive phases in the course of exchange lasting for several hours are the main features of ultrafiltration during peritoneal dialysis. The first phase includes positive ultrafiltration, transport of water and soluble substances from the blood into the dialysate. Peritoneal volume increases gradually up to a certain maximum. Time needed to achieve that depends on the glucose concentration in the dialysate and time. The second phase starts when osmotic concentration of peritoneal solution becomes lower than osmotic concentration of the blood due to glucose resorption. It results in negative ultrafiltration, i.e. return of water and soluble substances from dialysis solution back into the blood: The paper reviews the production of concentration haemodialysis solutions at the Department of Pharmacy. Military Medical Academy, Belgrade. The first series of 3400 liters was produced during 1971. It is only 3% of the current production. Ever since, the extent of production and number of new products have increased annually. Today, 2500 lit of five types of solutions for hemodialysis are manufactured weekly at the Institute of Pharmacy. The quality of these solutions is secured by good manufacturing practise, quality control of substances and physico-chemical control of the produced solutions. The Institute of Pharmacy collaborates with the Clinic of Nephrology permanently improving and adjusting the production program.