Experience with enteral nutrition in a hospital population of acutely ill patients.

Enteral feeding has unique metabolic and immune advantages. This article describes the successful use of enteral nutrition, alone or in combination with parenteral feeding, in a tertiary-care hospital. Study participants were 89 patients who received enteral feeding during a 6-month period. These critically ill patients (ranging in age from 55 to 71 years) had severity of illness levels of 7 to 25 according to the Acute Physiologic and Chronic Health Evaluation (APACHE II) system and lengths of hospital stay from 27 to 73 days. Mortality was as high as 50% in patients with liver disease (nonmalignant), 35% in patients with cardiothoracic and vascular diseases, and 17% in patients with cancer and other diseases. Despite the severity of illness, patients met their energy and protein intake goals through enteral or combined feeding with total parenteral nutrition. Serial weights (ie, obtained weekly) and serum albumin concentrations did not improve during hospitalization. Complications related to enteral feeding were minimal (< 17% incidence). Differences were noted between survivors and nonsurvivors: nonsurvivors had lower serum albumin concentrations at the time of admission, had longer hospitalizations, and required total parenteral nutrition for more days than the survivors. Nonetheless, even with extremely sick patients, provision of enteral nutrition can be successful using the administration techniques we describe. Enteral nutrition could best be provided by beginning at a slow rate (10 c3/hour), inserting the feeding tube past the pylorus, and feeding according to sensible energy goals (25 kcal/kg of body weight), and using elemental then polymeric formulas.

A chemical score to evaluate the protein quality of commercial parenteral and enteral formulas: emphasis on formulas for patients with liver failure.

Essential amino acids, found in abundance in high-quality dietary protein, are required daily by hospitalized patients and healthy persons to maintain the dynamic process of protein metabolism. One method for assessing dietary protein quality is by determining a diet's chemical score, ie, the ratio of a gram of the limiting amino acid in a test diet to the same amount of the corresponding amino acid in a reference diet (eg, whole-egg protein) multiplied by 100. This investigation used the chemical score to evaluate the protein quality of 9 parenteral and 17 enteral diets commonly used to feed hospitalized patients. Standard parenteral and enteral products (ie, formulas that had not been designed for patients with a specific disease state) had chemical scores that ranged from 46% to 70%. Limiting amino acids were either methionine (plus cysteine) or phenylalanine (plus tyrosine). Products designed for patients with renal failure had the highest scores, which ranged from 85% to 145%. Products that were enriched with branched-chain amino acids for trauma patients had scores that ranged from 38% to 73%. The only product available for patients with pulmonary compromise had a score of 50%. The lowest scores, which ranged from 5% to 13%, were found in products for patients with hepatic failure. All products, except those with chemical scores below 13%, may be fed in relatively small amounts of protein (7 to 33 g) to satisfy the minimum daily requirements of essential amino acids, although such levels would not meet minimal daily nitrogen requirements. We recommend that dietitians use the chemical score to assess the protein quality of parenteral and enteral diets.

The effect of nutritional support on T-lymphocyte subpopulations in protein calorie malnutrition.

T-lymphocyte subpopulations were measured in the two major types of adult malnutrition, adult marasmus and kwashiorkor-like hypoalbuminemic malnutrition. The population of T-cells (T3) and the percentage of both helper (T4) and suppressor (T8) T-cells were significantly (P less than .05) decreased in patients with kwashiorkor-like hypoalbuminemic malnutrition, but did not differ from control values in patients with adult marasmus. The ratio of helper T-cell (T4), to suppressor T-cells (T8) (range 1.2-1.6) did not vary from control values in either type of malnutrition. One week of nutritional support was not associated with a significant increase in any of the T lymphocyte subpopulations in either type of malnutrition. These T-cell subpopulation changes are consistent with the greater depression of cellular immune function seen in patients with metabolic stresses associated with kwashiorkor-like hypoalbuminemic malnutrition. With the increasing frequency in which abnormalities of T-cell subpopulations are being reported in various diseases, the coexistence of kwashiorkor-like hypoalbuminemic malnutrition should be noted for its potentially confounding effect.