Parenteral nutrition in renal failure

Nutrition and the kidney: how to manage patients with renal failure

Nutrition is believed to play a key role in the management of chronic and acute renal failure. Considerable evidence suggests that unrestricted protein diets accelerate the progression of chronic renal failure. As a result, recommendations have evolved limiting the quantity and quality of nitrogen intake with the goal of slowing the progression to dialysis dependency. Acute renal failure offers different challenges in view of its common association with hypermetabolic states. With respect to nitrogen substrate administration, the use of mixed formulations of essential plus nonessential amino acids seems to be as effective as essential amino acids alone.

Nutritional support in the critical care setting (Part 1)

Over the past two decades nutritional support has rapidly become an integral part of the medical care of critically ill patients. As scientific evidence accumulates supporting the important role of underlying nutritional status in determining the eventual outcome of many illnesses, aggressive nutritional intervention has become commonplace in our medical and surgical ICUs. However, nutritional support, particularly parenteral alimentation, is expensive and associated with important morbidity and even mortality. Furthermore, definite evidence of its clinical efficacy under certain specific conditions is often lacking and in need of properly done prospective studies. This review summarizes the basic principles of nutrition as applied to the critically ill patient in the clinical setting. Special emphasis is on practical considerations regarding cost, efficacy (or lack thereof), and potential advantages, disadvantages, and risk of complications of each proposed approach.

Disorders of urine volume in the critically ill child

This article will provide a pathophysiologic basis for the assessment of critically ill children who have developed disorders of urine volume. The anatomical and pathophysiologic causes of oliguria and polyuria are considered. The physiologic basis for the use of urinary sodium and osmolarity as a guide to the assessment of patients with disorders of urine volume are discussed in detail. In addition, guidelines for the management of children with acute renal failure, with particular emphasis on the consideration for nutritional support of these patients, is discussed as a part of the comprehensive approach to this problem. This article emphasizes an understanding of the pathophysiology of salt and water excretion by the kidney as a foundation to the diagnosis and management of patients with oliguria and polyuria.

Fat elimination in acute renal failure

Lipid metabolism and elimination of parenterally administered fat were investigated in 15 patients with acute renal failure (ARF). The mean triglyceride level was elevated to 2.56 +/- 1.43 mmol/l and the mean cholesterol level was 3.32 +/- 0.66 mmol/l, which is slightly below the normal range. A type IV hyperlipoproteinaemia was present in 47 per cent of the patients. The triglyceride content of LDL and VLDL was elevated and the cholesterol concentration of HDL and of LDL was reduced markedly. The fractional removal rate of triglycerides (K2) evaluated by an intravenous fat tolerance test using a bolus technique was reduced to 2.44 +/- 1.56 per cent/min which is about half of normal and correspondingly the elimination half life was prolonged to 28.4 min. No correlation could be demonstrated between the impairment of fat elimination and residual renal function, basal and VLDL triglyceride concentration or HDL cholesterol content.

Splenic lipidosis after administration of intravenous fat emulsions

Spleens showing fatty infiltration and necrosis of the pulp were found at necropsy on several patients who had received intravenous fat emulsions during their terminal illnesses. The postmortem findings are described and the clinicopathological correlation is discussed with special reference to the phenomenon of creaming of the emulsion.

Prognostic significance of serum albumin urea ratio in suture line leakage of the alimentary tract

Prognostic significance of postoperative changes in serum albumin and urea concentrations as well as their ratio was statistically evaluated in 73 patients with suture line leakage of the abdominal alimentary tract. Increase in serum urea was associated with poor prognosis regardless of the site of leakage. Although the serum albumin concentration was poorly correlated to prognosis, its ratio to serum urea was of more prognostic significance than the urea value alone. When the ratio of the serum albumin nitrogen to the urea nitrogen fell below 10, there was a sharp rise in mortality as well as in morbidity, associated with poor local defense reaction, high incidence of spreading peritonitis, severe systemic complications, and decreased tolerance to tube feeding as well as parenteral hyperalimentation. A special therapeutic policy was suggested for the management of leakage in patients with critically low albumin/urea ratios.