Adding Urea to the Final Dialysis Fluid

At times patients with advanced renal failure present with severe hyperkalemia or acidosis and very high serum blood urea nitrogen (BUN) concentrations. These patients cannot be dialyzed aggressively as the lowering of serum BUN may results in disequilibrium syndrome but on the other hand they need aggressive dialysis in order to lower their serum potassium or fix their severe acidosis. If one is able to add urea to the dialysis fluid, one can prevent the rapid lowering of serum BUN and osmolality at the same time as doing aggressive dialysis to lower serum potassium and/or fix the metabolic acidosis.