Hemodialysis

Hemodialysis removes uremic toxins, excess fluid, and metabolic waste products by circulating the patient's blood across a semipermeable membrane (dialyzer) in contact with dialysate solution. Solute removal occurs via diffusion (movement down concentration gradients from blood to dialysate for urea, creatinine, and potassium) and convection (solute dragged with water during ultrafiltration). Fluid removal (ultrafiltration) is achieved by applying transmembrane pressure to move water from blood to dialysate compartment. Dialysis adequacy is quantified by Kt/V (target greater than 1.2) and urea reduction ratio (target greater than 65%). The nurse managing hemodialysis must understand vascular access types (arteriovenous fistula, graft, central venous catheter), recognize acute complications (intradialytic hypotension from rapid fluid removal, disequilibrium syndrome from rapid urea clearance causing cerebral edema, air embolism, hemolysis from dialysate errors), manage anticoagulation during treatment, and coordinate the complex chronic disease management of end-stage renal disease patients including erythropoietin therapy, phosphate binder administration, and dietary restrictions.