How should we measure peritoneal dialysis adequacy in the clinic.

Several different dialysis adequacy indices have been suggested for peritoneal dialysis (PD) patients, but at present mainly Kt/V urea (urea clearance normalized to total body water) and to some extent weekly creatinine clearance (normalized to body surface area) are used as estimates of PD adequacy. These indices can easily be calculated from a 24-hour collection of dialysate and urine, which may also be used to evaluate several other aspects of the dialysis adequacy and the dialysis process including fluid and sodium removal, protein intake, peritoneal albumin clearance and a rough estimate of the diffusive transport. Today, there is general agreement that the target Kt/V urea in PD patients should be 1.7 or higher. However, PD adequacy should also involve many other aspects of the treatment, such as fluid status, adequate mineral metabolism, control of phosphate levels, anemia and acidosis, treatment of comorbidity, and prevention of cardiovascular and infectious complications.