SURGICAL ACCESS FOR CHRONIC DIALYSIS

Abstract

The kidney has one major function, to maintain nearly const<mt the volume ,md composition of body fluids in the face of fluctu.1tions in the volume and composition of daily intake, thus permitting safe habitation in a wide range of external environments (Andereoli et i.ll, 1990).

The regulation is precise, and the kidney can adjust to major variations in intake or production of different substances (Field et al , 1994). The renal contribution to the homeostasis of body fluids

involves a number of individual, specialized renal functions; these include the excretion of metabolic end products and toxins, the regulation of body fluid volume and solute composition, and additional metabolic and honnon.1l functions (Andreoli et al, 1990).

The kidney filters a large volume of blood each day, and from this filtrate most of the sodium chloride and bicarbonate and water is reabsorbed, together with other small, import<mt substances, e.g phosphate. In addition there is selective reabsorption of essential molecules like amino acids and glucose, and specific secretion of unwanted substances (Field et al, 1994).