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.