Past, present, and future of quantified peritoneal dialysis.

The role of peritoneal dialysis (PD) as a modality in renal replacement therapy has been well established. In this article we review various aspects in the evolution of PD, with special emphasis on adequacy. Until the late 1950s PD was still considered as a last resort in the treatment of terminal uremia. The introduction of a chronic indwelling catheter made chronic PD possible. The concept of continuous ambulatory peritoneal dialysis (CAPD), proposed in 1975, had a major impact on the way PD was performed later. The value of determining the adequacy, using urea clearance normalized to total body water (Kt/V) or creatinine clearance normalized to body surface area, was clearly highlighted by the Canada-USA (CANUSA) study. Introduction of standardized peritoneal equilibration tests has been very helpful in enhancing the efficiency of PD. In 1995 the National Kidney Foundation-Dialysis Outcomes Quality Initiatives (NKF-DOQI) established guidelines to improve patient survival and outcome on dialysis. These guidelines established minimum criteria for PD adequacy. Compliance and malnutrition remain important factors determining the efficacy of PD. The "healthy start" concept emphasizes an early start of dialysis in patients with end-stage renal disease (ESRD). The quest for an ideal PD modality has recently led to renewed interest in the idea of continuous flow peritoneal dialysis (CFPD). PD continues to grow and at the same time faces many challenges. Its role as a renal replacement therapy is likely to evolve further in the years to come.