[Terminal chronic kidney failure: treatment by dialysis. Confirmations and controversies after 35 years of experience].

There are currently more than 500,000 people on long-term renal dialysis throughout the world, some have been treated for more than 20 years. Despite this major success in the treatment of chronic renal failure, many unsolved problems remain, often leading to controversial debate. Should dialysis be "adequate" or "optimal"? To answer this question results are evaluated on the basis of mid-term and long-term survival rates, morbidity and quality of life criteria including psychological tolerance. While the need for a reliable vascular access and an appropriate dialysis system is obvious for haemodialysis, debate has focused on the optimal dialysis time; total weekly duration under 10-11 hours is sometimes advocated. Nephrologists have emphasized that peritoneal dialysis frees patients from the risk of vascular puncture and the need for anticoagulation while providing better haemodynamic stability. The higher morbidity and risk of infectious complications are however major drawbacks of peritoneal dialysis. Both techniques may require use of recombinant human erythropoietin and daily protein intake of about 1.2 g/kg body weight is mandatory. Despite all the progress made in dialysis concepts and technical applications, several factors may lead to "inadequate" dialysis in some patients. Some, such as insufficient blood flow, are subject to corrective measures, others are cost-related. What is the optimal duration of a dialysis session? How often should dialysers be reused? Are bio-compatible membranes or systems for producing sterile haemodialysis fluid cost-effective? Finally, our understanding of the uraemic toxicity syndrome is still insufficient for a totally satisfactory treatment of renal failure. Further advances in technology and in our understanding of the pathophysiology of renal function and dialysis are needed to reduce morbidity of patients treated for end-stage chronic renal failure and improve their quality of life.