[Nutrition and renal insufficiency]

Renal failure patients in the intensive care unit comprise a heterogeneous group of subjects with widely differing metabolic patterns and nutritional requirements. This group includes patients with acute kidney injury (AKI), acute-on-chronic renal failure, chronic kidney disease, and those on regular hemodialysis therapy. Renal failure is associated with a broad spectrum of specific metabolic alterations. In addition to these alterations and the often underrated impact of renal replacement therapy, the metabolism is also affected by the underlying disease process as well as associated organ failures and complications, especially infections. Nutritional support for renal failure is not fundamentally different from other disease processes, but in designing a nutrition regimen the variations in metabolism and nutrient requirements should be considered. Nutritional needs can differ widely between patients but also in the same patient during the course of disease. Thus, patients with renal failure require an individualized approach to nutritional support. Moreover, because of the altered metabolism of many nutrients and the intolerance of fluids and electrolytes, close monitoring of the nutritional therapy is mandatory in patients with renal failure.