The nutrition management of the patient with acute renal failure

The clinical status of patients with acute renal failure (ARF) varies greatly. Some individuals have only mild or moderate ARF or may have only mild perturbations of their metabolic status. Other patients exhibit a severe reduction in renal function with oliguria or anuria. Depending upon their comorbid conditions, ARF patients may be among the most hypercatabolic patients in the hospital. Clinical trials have not clearly shown a beneficial effect of nutrition support on morbidity or mortality in patients with ARF, although limitations in sample size and experimental design and inclusion of patients with widely disparate clinical conditions may have contributed to the difficulty in demonstrating benefits. Several recent therapeutic approaches that have been studied either in experimental animals with ARF or in small numbers of humans with ARF hold promise for improving clinical outcome. Continuous arteriovenous or venovenous hemofiltration with or without dialysis is such a therapy. In comparison to intermittent hemodialysis this former treatment more safely removes large quantities of water and solutes from critically ill patients with unstable hemodynamics and allows them to receive rather large quantities of nutrients, including amino acids. Also promising are studies in experimental animals with ARF which indicate that several growth factors may accelerate the recovery of renal function. In rats with ARF, insulin-like growth factor 1 both enhances recovery of renal function and suppresses their enhanced catabolism. For most patients with ARF requiring nutrition support, evidence suggests that both essential and nonessential amino acids should be employed. However, there appears to be a therapeutic role for small quantities of essential amino acids, without nonessential amino acids, in selected patients. Data support the importance of proactive measures to prevent fluid and electrolyte imbalances in patients with ARF.