Role of the dialyzer membrane on the overall phosphate kinetics during hemodialysis.
OBJECTIVE
We investigated the potential role of the membrane type on phosphate kinetics.


METHODS
Six patients on dialysis (HD) were studied using modified cellulose (Hemophan), ethylene-vinyl alcohol (EVAL) and polyacrylonitrile (PAN). Total (TPR), extracellular (EPR) and intracellular (IPR) phosphate removal and effective dialyzer phosphate clearance (K(d)) were determined by the DDQ method. The intercompartment transfer coefficient (K(C)) was calculated using a mathematical model. Erythrocyte phosphate (P(ERY)) and 2,3-biphosphoglycerate (2,3-BPG) concentrations were determined before and after HD.


RESULTS
TPR was 1.2+/-0.4, 1.10+/-0.4 and 1.09+/-0.4 g with Hemophan, EVAL and PAN, respectively (p=n.s.). EPR and IPR were independent of membrane type. There was no difference in K(C) between membranes (321+/-70, 338+/-92 and 341+/-83 ml/min, respectively). The P(ERY) and 2,3--BPG remained statistically insignificant for all membranes.


CONCLUSIONS
Our results show that the type of membrane does not influence the kinetics of phosphate during dialysis, neither in the transfer from plasma to dialysate nor from the intra- to the extracellular compartment.
Katopodis
Konstantinos P
KP
Department of Nephrology, University Hospital of Ioannina, Ioannina, Greece.
Chala
Anna
A
Koliousi
Elli
E
Takouli
Lamprini
L
Kalaitzidis
Rigas
R
Theodorou
Joanna
J
Siamopoulos
Kostas C
KC
D000180:Acrylic Resins; D000328:Adult; D000368:Aged; D002482:Cellulose / Q000031:analogs & derivatives; D005260:Female; D006801:Humans; D007700:Kinetics; D008297:Male; D008567:Membranes, Artificial; D008875:Middle Aged; D010710:Phosphates / Q000097:blood* / Q000302:isolation & purification; D011145:Polyvinyls; D006435:Renal Dialysis / Q000295:instrumentation*
D000180:Acrylic Resins; D008567:Membranes, Artificial; D010710:Phosphates; D011145:Polyvinyls; C054645:Hemophan; C010504:polyacrylonitrile; C020320:ethylene-vinyl alcohol copolymer; D002482:Cellulose