[Biological adequacy--what does it mean?]

Appropriate initiation of dialysis is of an outstanding importance in the treatment of patients with end-stage renal disease. It prevents development of irreversible uremic complication and enables selection of the most appropriate dialysis modality for the individual patient. The major causes of morbidity and mortality in dialysis patients are cardiovascular diseases. Hypertension and hyperlipidemia are commonly found in dialysis patients as well as anemia, chronic inflammation and fluid overload, all of which are found to be risk factors for the development of cardiovascular diseases. Arterial hypertension is the main risk factor for left ventricular hypertrophy, and there is clear evidence that control of hypertension has a beneficial effect on left ventricular hypertrophy. It is best achieved by correction of overhydration and maintenance of dry weight. Modern dialysis machines are capable of changing electrolyte concentrations, which reduces intradialytic cardiovascular complications, incidence of cardiac arrhythmias and hypotension. Correction of anemia with erythropoietin results in regression of left ventricular hypertrophy and improvement of the quality of life and defense against microorganisms. Chronic inflammation can be prevented with the use of biocompatible high-flux dialysis membranes and sterile dialysate, which are also important for the prevention of oxidative stress involved in the increase of LDL oxygenation and incorporation into the intimal layer of the vessels. Low molecular weight heparins by their action on lipoprotein lipase serve as an additional factor that suppresses development of atherosclerotic plaque in dialysis patients. Optimal dialysis dose decreases the mortality and morbidity rates. High-flux membranes or prolongation of dialysis session are modalities for dialysis dose improvement. Individualized approach to preparation of dialysis solutions has resulted in better control of fluid overload and intradialytic hyper- or hypotension, reduction in the incidence of arrhythmias, improvement of hemodynamic stability, and delay of renal osteodystrophy. Malnutrition is a relatively common problem in dialysis patients that may be secondary to poor nutritional intake, inadequate amount of dialysis, lack of appetite, acidosis, associated disease, and/or increase in protein catabolism. The most appropriate approach includes individualization of dietary prescription according to the nutritionist's advice, increase of dialysis dose with biocompatible membranes, and use of sterile bicarbonate dialysate with glucose and erythropoietin. The major goal of adequate dialysis is not just improvement in survival of dialysis patients, but also improvement in the quality of their lives.