CHRONIC RENAL FAILURE

Chronic Renal Failure

Chronic Renal Failure

Pathophysiology

The kidney suffers from a chronic disease behaves as if he had lost a part of His remaining nephrons and those were still intact (Ward, 2005). In a chronic kidney disease substantial part of renal function may be lost without the occurrence striking alterations in fluid balance. This is due to the ability of the nephrons residues (which behave as if they were normal) to increase the fraction excreted sodium and water filtered (US Census Bureau, 2004). However, the increase of the fraction excreted sodium and water occur precisely because the extracellular volume is expanded. The increase in the fraction excreted indicates, therefore, a renal failure, namely the inability of the kidney to maintain homeostasis of the VEC (Janssen & Katzmarzyk, 2004). The kidney is not enough operate normally, even as an organ of excretory metabolites, either as producing hormones (erythropoietin, vitamin D).

Pathophysiology

When renal blood flow decreases, so does the basic driving force filtration. Also, the kidneys no longer receive oxygen and other nutrients vital to the cellular metabolism. As a result of the decrease in glomerular filtration is waste products accumulate in the body and therefore, the patient will experience increase in serum creatinine and BUN (blood urea nitrogen), which azotemia called (McCulloch & Iribarren, 2006). To avoid renal hypoperfusion requiring kidney Mean arterial pressure of at least 60-70 mmHg, in case of not reaching this pressure the kidneys are launched two important adaptive responses: Autoregulation: Keeps glomerular hydrostatic pressure through the expansion of the afferent arteriole and constriction of the efferent arteriole saw increases blood flow in the glomerular capillary bed and delaying the output of blood from same, obtaining a pressure increase and the rate of glomerular filtration. Activation of the renin-angiotensin-aldosterone system (Iseki & Ikemiya, 2004). This system stimulates ...