Clinical benefit of preserving residual renal function in dialysis patients: an update for clinicians.

Residual renal function (RRF) remains important even after beginning of dialysis. RRF contributes significantly to the overall health and well-being of patients on dialysis. It plays an important role in maintaining fluid balance, phosphorus control, nutrition, and removal of middle molecular uremic toxins and shows inverse relationships with valvular calcification and cardiac hypertrophy in patients on dialysis. RRF may allow for a reduction in the duration of hemodialysis sessions and the need for dietary and fluid restrictions in both patients on peritoneal dialysis and hemodialysis. More importantly, the loss of RRF is a powerful predictor of mortality. This article will review the evidence supporting the importance of RRF on outcome and outline potential strategies that may better preserve RRF in patients on dialysis.