ADHERENCE OF METALS TO CELLOPHANE MEMBRANES AND REMOVAL BY WHOLE BLOOD. A MECHANISM OF SOLUTE TRANSPORT DURING HEMODIALYSIS

Serum copper concentration changes in chronic hemodialyzed patients

We studied the behavior of copper during hemodialysis and the relationship between serum copper levels and hematologic parameters such as red blood cell count (RBC), hematocrit (Hct), hemoglobin (Hb), and serum iron in 48 hemodialyzed patients. To study diffusion, we measured copper in the arterial blood and in the dialysate at the inflow and outflow sites of the dialyzer. To study hemoconcentration, the change in hematocrit values and total serum protein values were examined. To study liberation of copper from the dialyzer membrane, copper concentrations in normal saline were measured before and after the saline was used to wash dialyzers of various kinds. We found that changes in serum copper concentration were due mainly to hemoconcentration and liberation, but partly also to diffusion, and that the net result of changes was a significant increase in serum copper. We observed no correlation between serum copper levels and RBC, Hct, Hb, and serum iron levels.

Principles of dialysis and dialysis of drugs

Consideration of the interactions of drugs and dialysis must include an understanding of the mechanisms of transport during dialysis, i.e., diffusion, ultrafiltration and membrane-protein binding effects. Clearance is a function of molecular size, blood and dialysate flow, membrane area and permeability, and dialyzer support geometry. Protein binding and hematocrit decrease the in vivo clearances in comparison to those measured in vitro with aqueous solutions. The effect on the serum half-life is also determined by the distribution space and clearance by other routes. Other factors such as metabolic alterations of dialysis can affect pharmacologic activity, and the clinical response is the end product of many determinants. Numerous drugs are effectively removed by hemodialysis or at a slower rate by peritoneal dialysis, which occasionally allows considerable influx. The influence of intestinal contents on elimination rates by peritoneal dialysis is unknown. Peritoneal dialysis can be influenced considerably by vasoactive drugs.

Haemodialysis and copper fever

A syndrome of headache, chills, sweating, nausea, and exhaustion during and after haemodialysis is described and likened to metal fume fever. A patient has been cured of this syndrome following removal of copper-containing parts from the water-path of her home dialysis system.

Acute zinc toxicity in haemodialysis

A country patient on home haemodialysis suffered acute nausea, vomiting, and fever during dialyses when she used water stored in a galvanized tank. She subsequently was found to have severe anaemia with raised plasma and erythrocyte zinc concentrations. Intercurrent hospital haemodialyses and subsequent home dialyses with deionized water were symptom-free.Experimental haemodialyses of dogs against small concentrations of zinc showed a disproportionate rise in plasma zinc and possible uptake of zinc by the liver.