Confounding factors in the assessment of delivered hemodialysis dose

A satisfactory dialysis patient's outcome results from an effective and personalized therapy. However, the higher the prescribed efficiency, the more likely it is that the prescribed dose is incorrectly administered. Avoiding discrepancies between the prescribed and delivered doses calls for a continuous surveillance, from urea kinetics to urea biosensors. An unexpectedly low efficiency result may affect several patients or may just be limited to the individual patient. An inadequate calibration of blood and dialysate pumps or manufacturing defects in blood tubings or needles may be responsible for a more diffuse phenomenon. The most frequently detected factors in the individual patient are poor vascular access, recirculation, decreases in dialyzer performance and insufficient anticoagulation. However, urea removal per se is not enough to satisfy all the assumptions underlying an adequate dialysis therapy. Indeed, dialysis adequacy is achieved by way of a complex combination of numerous elements transcending urea removal alone: acidosis correction, the achievement of dry body weight, fluid and electrolyte homeostasis, good blood pressure control, overall biocompatibility, anemia and malnutrition correction, and finally, a customized schedule together with treatment duration.