dialysator

Dialysator, also known as a dialyzer, is a medical device used in hemodialysis to remove waste products and excess fluids from the blood when kidney function is impaired. It consists of a blood compartment and a dialysate compartment separated by a semi-permeable membrane. Blood flows on one side of the membrane, while dialysate flows on the opposite side; solutes and water diffuse or are ultrafiltered across the membrane according to size, concentration, and transmembrane pressure.

Most modern dialyzers use hollow-fiber or flat-plate membranes made from synthetic polymers such as polysulfone, polyethersulfone, or polyacrylonitrile, and may be described as low-flux or high-flux based on permeability. Materials derived from cellulose are found in older designs. The device's performance is assessed by solute clearance (for example urea and creatinine) and by dialysis dose metrics such as Kt/V.

Dialysis treatment requires anticoagulation to prevent clotting of the blood in the circuit. In some settings dialyzers are sterilized and reused between patients, though many programs use single-use devices. Reprocessing and reuse require strict adherence to sterilization protocols and regulatory standards.

Potential risks during dialysis include hypotension, muscle cramps, disequilibrium syndrome, and, rarely, air embolism. Proper circuit priming, monitoring, and adherence to protocols reduce these risks. Regulatory oversight for dialyzers varies by country, with agencies such as the United States Food and Drug Administration and European CE marking governing safety and performance.