Standard Enteral Formula Research Articles

The In Vitro Effect of the Addition of Ion Exchange Resins on the Bioavailability of Electrolytes in Artificial Enteral Feeding Formulas

ObjectiveTo determine in vitro free ion concentration in 3 standard artificial enteral feeding formulas following the addition of ion exchange resins. MethodThree standard types of AEF were chosen: Osmolite HN®, Nutrison Standard®, and Isosource Standard®. The ion exchange resins used were: sodium polystyrene sulfonate and calcium polystyrene sulfonate. In a beaker were mixed 100mL of AEF with 1.5g or 3g of ion exchange resins for 48 hours at 37°C. Subsequently, the samples were precipitated and the supernatant obtained was used for determining the concentrations of calcium, magnesium, sodium, and potassium ions. ResultsThe addition of sodium polystyrene sulfonate to different types of enteral feeding formulas reduced the concentrations of potassium, calcium, and magnesium ions by 70%, 78.2%, and 77.6% in the case of Osmolite HN®; by 72.3%, 69.2%, and 63.5% in the case of Nutrison Standard®; and by 78.3%, 80.5%, and 74.5% in the case of Isosource Standard®. In contrast, the addition of calcium polystyrene sulfonate reduced the concentration of potassium and magnesium by 50.5% and 55.5% in the case of Osmolite HN®; by 49.8% and 43% in the case of Nutrison Standard®; and by 42.6% and 37.7% in the case of Isosource Standard®. ConclusionThe addition of ion exchange resins to different types of enteral feeding formulas, allows the in vitro free ion content of these to be reduced.

Synbiotics, Prebiotics, Glutamine, or Peptide in Early Enteral Nutrition: A Randomized Study in Trauma Patients

Since the hepatosplanchnic region plays a central role in development of multiple-organ failure and infections in critically ill trauma patients, this study focuses on the influence of glutamine, peptide, and synbiotics on intestinal permeability and clinical outcome. One hundred thirteen multiple injured patients were prospectively randomized into 4 groups: group A, glutamine; B, fermentable fiber; C, peptide diet; and D, standard enteral formula with fibers combined with Synbiotic 2000 (Synbiotic 2000 Forte; Medifarm, Sweden), a formula containing live lactobacilli and specific bioactive fibers. Intestinal permeability was evaluated by measuring lactulose-mannitol excretion ratio on days 2, 4, and 7. No differences in days of mechanical ventilation, intensive care unit stay, or multiple-organ failure scores were found between the patient groups. A total of 51 infections, including 38 pneumonia, were observed, with only 5 infections and 4 pneumonias in group D, which was significantly less than combined infections (p = .003) and pneumonias (p = .03) in groups A, B, and C. Intestinal permeability decreased only in group D, from 0.148 (0.056-0.240) on day 4 to 0.061 (0.040-0.099) on day 7; (p < .05). In group A, the lactulose-mannitol excretion ratio increased significantly (p < .02) from 0.050 (0.013-0.116) on day 2 to 0.159 (0.088-0.311) on day 7. The total gastric retention volume in 7 days was 1150 (785-2395) mL in group D, which was significantly more than the 410 (382-1062) mL in group A (p < .02), and 620 (337-1190) mL in group C (p < .03). Patients supplemented with synbiotics did better than the others, with lower intestinal permeability and fewer infections.

Efficacy of Enteral Nutrition for the Treatment of Pancreatitis Using Standard Enteral Formula

Efficacy of Enteral Nutrition for the Treatment of Pancreatitis Using Standard Enteral Formula

Efficacy of Enteral Nutrition for the Treatment of Pancreatitis Using Standard Enteral Formula

Elemental formula delivered distal to the ligament of Treitz has demonstrated efficacy in patients with pancreatitis, presumably by decreasing pancreatic stimulation. Few data exist on the use of standard enteral formula in such patients. This study describes the outcomes of pancreatitis patients managed with long-term standard enteral nutrition (EN). One hundred twenty-six patients managed at the University of Virginia Health System with pancreatitis requiring nutritional support between August 2000 and June 2004 received a standard formula delivered distal to the ligament of Treitz and were followed prospectively to resolution of their disease process. Predictors of improvement in CT Severity Index, duration of EN, and length of hospital stay were identified. Changes in body weight and serum albumin were determined. Mean age was 50.8 +/- 15.2 yr (male, 83). Etiology included alcohol (46), gallstones (49), idiopathic (15), post-ERCP (7), drug (5), hyperlipidemia (3), and pancreas divisum (1). EN lasted a median of 18.9 (2.4 to 111.7) wk. Median CT Severity Index decreased from 4 to 2 (p < 0.001). Underweight patients gained 9.8 lbs; overweight and obese patients lost 7.2 and 28.8 lbs, respectively. Albumin concentration increased from 3 to 3.8 g/dL (p < 0.001). Standard enteral formula is effective in the management of patients with complicated pancreatitis.

Evaluation of Nutritional Status in Cancer Patients Receiving Radiotherapy

The purpose of the present study was to evaluate the nutritional status of cancer patients receiving radiotherapy (RT) and to assess the possible contributions of nutritional support to patients with malnutrition. Prospectively, 207 patients referred to our outpatient radiotherapy department were included. The patients were classified according to tumor site (head/neck, breast, lung, stomach, or colorectal). Nutritional status at the onset, at the end of RT, and 3 and 6 months after irradiation was evaluated with the subjective global assessment (SGA). All of the patients were supported with additional portions of meal or standard enteral feeding formula during and after the irradiation period as long as they were in the moderately or severely malnourished groups, respectively. At the onset, malnutrition was present in 31% of all patients, and it increased to 43% at the end of RT. This difference predominated in head/neck cancer patients. Malnutrition ratios in head/neck cancer patients at the onset and after RT were 24% and 88%, respectively. By a 6-month follow-up, the ratio of patients with malnutrition decreased to 8%. Nutritional status of all groups was found to improve during the 6-month follow-up period, except for the breast cancer group, which included no patients with severe malnutrition at any time. The results of the present study may be helpful in planning an appropriate nutritional support for cancer patients undergoing radiotherapy according to the irradiation site.

ESPEN Guidelines on Enteral Nutrition: Intensive care

Enteral nutrition (EN) via tube feeding is, today, the preferred way of feeding the critically ill patient and an important means of counteracting for the catabolic state induced by severe diseases. These guidelines are intended to give evidence-based recommendations for the use of EN in patients who have a complicated course during their ICU stay, focusing particularly on those who develop a severe inflammatory response, i.e. patients who have failure of at least one organ during their ICU stay. These guidelines were developed by an interdisciplinary expert group in accordance with officially accepted standards and are based on all relevant publications since 1985. They were discussed and accepted in a consensus conference. EN should be given to all ICU patients who are not expected to be taking a full oral diet within three days. It should have begun during the first 24h using a standard high-protein formula. During the acute and initial phases of critical illness an exogenous energy supply in excess of 20-25 kcal/kg BW/day should be avoided, whereas, during recovery, the aim should be to provide values of 25-30 total kcal/kg BW/day. Supplementary parenteral nutrition remains a reserve tool and should be given only to those patients who do not reach their target nutrient intake on EN alone. There is no general indication for immune-modulating formulae in patients with severe illness or sepsis and an APACHE II Score >15. Glutamine should be supplemented in patients suffering from burns or trauma.

Etiology and Initial Management of Short Bowel Syndrome

o he normal human small intestine ranges between 3 and 8 m in length, depending on whether measureent is made by radiologic or surgical techniques or at utopsy when the intestine may be desicated.1–5 Short owel syndrome is defined in adults as 200 cm of small ntestine. Although usually acquired because of one or ore enterectomies, short bowel syndrome may also be ongenitally acquired. Nutrient, electrolyte, and fluid bsorption is proportional to the amount of residual ntestine. The degree of intestinal function is better escribed in terms of energy absorption/loss rather than ength of residual intestine.6 Intestinal failure may be efined as the inability to sustain adequate nutritional, lectrolyte, or hydrational status in the absence of speialized nutritional support. This requires an increase in ral intake because absorption is compromised. Clinially, nutrient assimilation is a function of intake and bsorption. As such, some patients with short bowel yndrome will not have sufficient loss of functional caacity as to develop intestinal failure. Significant indiidual variability in jejunal absorption efficiency may be ncountered.7 The patients with the greatest risk for development of ehydration, generalized protein-calorie malnutrition, nd multiple nutrient deficiencies are those with a duoenostomy or jejunoileal anastomosis and 35 cm of esidual small intestine; jejunocolic or ileocoloic anastoosis, and 60 cm of residual small intestine; or end ejunostomy with 115 cm of residual small intesine.6,8–11 Those patients with residual colon in continuty will have enhanced energy and fluid absorption. ence, such patients can tolerate greater loss of small ntestine and retain their nutritional autonomy.

Pediatric Enteral Nutrition

Common to all pediatric patients receiving enteral nutrition is the inability to consume calories orally. This is often secondary to issues of inadequate weight gain, inadequate growth, prolonged feeding times, weight loss, a decrease in weight/age or weight/height ratios, or a persistent triceps skinfold thickness <5% for age. Enteral nutrition requires enteral access. In the neonatal period the nasoenteric route is usually used. In pediatric patients requiring long-term enteral access, surgically, endoscopically, or radiologically placed percutaneous feeding tubes are common. Jejunal feeding tubes are used in pediatric patients with gastric feeding intolerance or persistent gastroesophageal reflux. Low-profile enteral access devices are preferred by most pediatric patients because of their cosmetic appearance. For most children, a standard pediatric polypeptide enteral formula is well tolerated. There are specialized pediatric enteral formulas available for patients with decreased intestinal length, altered intestinal absorptive capacity, or altered pancreatic function. Weaning patients from tube feeding to oral nutrition is the ultimate nutrition goal. A multidisciplinary approach to patients with short bowel syndrome will maximize the use of enteral nutrition while preserving parenteral nutrition for patients with true enteral nutrition therapy failure.

Fructooligosaccharides and Fiber Partially Prevent the Alterations in Fecal Microbiota and Short-Chain Fatty Acid Concentrations Caused by Standard Enteral Formula in Healthy Humans

The intestinal microbiota are important during enteral tube feeding because they exert colonization resistance and produce SCFAs. However, the effect of the enteral formula composition on major bacterial groups of the microbiota has not been clearly defined. The aim of this study was to investigate the effect of enteral formulas with and without prebiotic fructooligosaccharides (FOS) and fiber on the fecal microbiota and SCFAs. Healthy subjects (n = 10; 4 men, 6 women) consumed both a standard enteral formula and one containing FOS (5.1 g/L) and fiber (8.9 g/L) as a sole source of nutrition for 14 d in a randomized, double-blind, crossover trial with a 6-wk washout phase. Fecal samples were collected at the start and end of each formula phase, and were analyzed for major bacterial groups and SCFA concentrations using fluorescent in situ hybridization and GLC, respectively. Although there were reductions in total fecal bacteria due to both formula treatments, concentrations were higher after the FOS/fiber formula period compared with the standard formula period (11.2 +/- 0.2 vs. 11.0 +/- 0.2 log(10) cells/g, P = 0.005). The FOS/fiber formula increased bifidobacteria (P = 0.004) and reduced clostridia (P = 0.006). Compared with the standard formula, the FOS/fiber formula resulted in higher concentrations of total SCFA (332.4 +/- 133.8 vs. 220.1 +/- 124.5 micromol/g, P = 0.022), acetate (219.6 +/- 96.3 vs. 136.8 +/- 74.5 micromol/g, P = 0.034) and propionate (58.4 +/- 37.4 vs. 35.6 +/- 25.5 micromol/g, P = 0.02). This study demonstrates that standard enteral formula leads to adverse alterations to the fecal microbiota and SCFA concentrations in healthy subjects, and these alterations are partially prevented by fortification of the formula with FOS and fiber.

Evolution of Fatty Acid Profile and Lipid Oxidation During Enteral Formula Storage

Enteral formulas can be stored for up to 2 years. Fat oxidation during storage can lead to the loss of nutritive value and generation of toxic products such as lipid peroxides. Two standard enteral formulas were stored for short periods at high temperatures (1-4 weeks at 32-55 degrees C) or for long periods at low temperatures (12-36 weeks at 4 degrees C, 20 degrees C, or 30 degrees C). The present study included the assessment of lipid oxidation by measuring related fluorescent compounds and the evolution of fatty acids profile. Enteral formula fat was oxidized under all assayed conditions, including storage at 4 degrees C. The loss of essential fatty acids (linoleic and linolenic acids) was always higher when time and temperature were increased. The omega6/omega3 ratio was increased by storage from 5.6 to 7.8, which could exacerbate the inflammatory response in critically ill patients. Fluorescence intensity increased with time and temperature of storage and was correlated with the decrease in essential fatty acids (lineal correlation between -0.9416 and -0.9996). Enteral formula fat was oxidized during storage, leading to a loss of nutritional value. These formulas should be stored under refrigeration to minimize this loss. Finally, fluorescence measurement proved to be a fast and easy method to assess fat oxidation status.

Efficacy of Home Enteral Nutrition for the Treatment of Pancreatitis Using Standard Enteral Formula

Efficacy of Home Enteral Nutrition for the Treatment of Pancreatitis Using Standard Enteral Formula

Role of Enteral Immunonutrition in Patients with Gastric Carcinoma Undergoing Major Surgery

To evaluate the influence of postoperative immunonutrition on immune and nutritional parameters in patients with gastric carcinoma. From September 2002 to August 2003, 40 patients with gastric carcinoma who had undergone major surgery were randomly divided into an immunonutrition group and standard nutrition group, each of 20 patients. On postoperative Day 2, patients in the standard nutrition group received a standard enteral formula, while those in the immunonutrition group received an enteral formula enriched with glutamine, arginine and omega-3 fatty acids. Nutritional support was continued for 7 days. Blood samples were obtained to determine plasma albumin, prealbumin and transferrin on Days 0, 5 and 9. On Days 0, 1 and 9, blood samples were collected to detect immunoglobulin (Ig) A, IgG, IgM, CD4 and CD8 cell counts, the ratio of CD4/CD8, interleukin (IL)-2, IL-6 and tumour necrosis factor (TNF)-alpha, respectively. There were no significant differences between the two groups in protein and immune parameters preoperatively and no significant differences in management perioperatively. No serious adverse effects were recorded with the two formulas. Postoperative procedures were smooth in both groups. On Day 9, serum levels of prealbumin and transferrin were higher in the immunonutrition group than in the standard nutrition group (p<0.01). After 7 days' nutritional support, patients in the immunonutrition group had higher levels of immunoglobulin, CD4 cell counts, CD4/CD8 ratio and IL-2 than those in the control group, whereas IL-6 and TNF-alpha levels were significantly lower in the immunonutrition group. Compared with standard enteral nutrition, enteral immunonutrition can improve defence mechanisms and modulate inflammatory action after major elective surgery for gastric carcinoma.

Immunonutrition in the critically ill: from old approaches to new paradigms

In this issue of Intensive Care Medicine, Keift et al. [1]report the results of a multicenter, randomized, double-blind, controlled trial comparing an enteral formula en-riched with arginine, glutamine, antioxidants and con-taining omega 3 fatty acids with an isocaloric, non-isonitrogenous standard enteral formula, in a mixedpopulation of 597 critically ill patients. When analyzedboth using an efficacy analysis (those fed for more than48 h) and by an intention-to-treat analysis, the authorsfailed to demonstrate any difference in clinical outcomesin the overall analysis or several subgroup analyses.Mortality, infectious complications, ICU length of stay,and duration of mechanical ventilation were the samebetween the two groups. Although the lack of a treatmenteffect on clinical outcomes has been shown in other trials,given the highly controversial nature of the topic of im-munonutrition in critically ill patients, this article is sig-nificant, particularly since this is the largest and one ofthe more robust randomized trials of immune-enhancingdiets in an ICU population.When the results of this large trial are added to theexisting trials, in the form of a meta-analysis, the overalltreatment effect is consistent with no effect on mortality(relative risk [RR] 1.05 and 95% confidence intervals [CI]0.89, 1.25), infectious complications (RR 0.97, CI0.81,1.15) or length of stay in ICU (weighted mean dif-ference [WMD] 1.59, CI 3.25,0.08) [2]. After 20 yearsof research, 18 randomized trials of 2,348 critically illpatients, and countless millions of research dollars, why isit that we are unable to demonstrate a positive treatmenteffect associated with these immune-enhancing products?Do we need more trials like this one to prove the virtuesof these special nutrients? Or, do we have to ask ourselveswhether there are fundamental problems with our ap-proach to proving the hypothesis that certain nutrientswith immunologic and metabolic properties will improvethe outcomes of critically ill patients? We have arguedbefore that there are significant methodological limita-tions to the existing literature that limit the inferences wecan make from these studies [3]. As we argue below,perhaps the problem is further compounded by the factthat multiple nutrients are combined into single nutri-tional products and tested in heterogeneous patient pop-ulations.For any sick patient, “metabolic resuscitation” of thegastrointestinal tract by providing adequate nutrition, ingeneral, and defined immuno-modulating substratesspecifically, to maintain gut-barrier integrity and functionand to reduce regional oxidative stress, will have to beconsidered as key therapeutic strategies. However, withina given patient over time or across different patientpopulations, the severity of “gut failure”, the amount ofbacterial translocation, the degree of cellular immunedysfunction, the balance of inflammation/anti-inflamma-tion, and the regional and systemic generation of reactiveoxygen species will vary. Generally speaking, electivesurgical patients experience minimal activation of cy-tokines and some degree of suppression of the cellulardefense function following surgical stress, putting them athigher risk for acquired infectious morbidity and mor-tality. It follows that nutrients, such as arginine, thatstimulate the cellular defense system may reduce infec-tious complications in the elective surgical patient. Incontrast, the associated changes to the systemic inflam-matory response accompanying critical illness are farmore intense, complex, variable, and less well-defined,but best characterized by an over-amplified inflammatory

Application of dietary fiber in clinical enteral nutrition: A meta-analysis of randomized controlled trials

To evaluate the effects of dietary fiber (DF) as a part of enteral nutrition (EN) formula on diarrhea, infection, and length of hospital stay. Following electronic databases were searched for randomized controlled trials about DF: Chinese Biomedicine Database (CBM), MEDLINE, EMBASE and Cochrane Controlled Trials Register. RevMan 4.1 was used for statistical analysis. Seven randomized controlled trials with 400 patients were included. The supplement of DF in EN was compared with standard enteral formula in five trials. Combined analysis did not show a significant reduction in occurrence of diarrhea, but there were valuable results for non-critically ill patients. Combined analysis of two trials observing the infection also did not show any valid evidence that DF could decrease the infection rate, though the length of hospital stay was reduced significantly. Based on the current eligible randomized controlled trials, there is no evidence that the value of DF in the diarrhea can be proved. Though length of hospital stay was shortened by the use of DF, there is no available evidence in preventing infection by DF. Further studies are needed for evaluating the value of DF in EN.

Reducing Costs and Patient Morbidity in the Enterally Fed Intensive Care Unit Patient

Critically ill patients are at high risk for nosocomial infections and resultant organ dysfunction and death. These patients typically have protracted intensive care unit (ICU) courses and consume increasingly limited resources. Enteral nutrition with specific immune-modulating components has been previously shown to improve outcomes in select populations of patients, but results have been mixed in critically ill patients. Impact 1.5 (Novartis Nutrition, Minneapolis, MN) is a commercially available enteral formula containing ingredients known to improve several parameters of immune function. We hypothesized that administration of Impact 1.5 tube feedings would reduce the incidence of nosocomial infection and ICU resources in critically ill patients admitted to the ICU for severe trauma, burns, or sepsis insults. The Impact 1.5 group (n = 17) was compared with a historical cohort of ICU patients (n = 21) of similar illness severity that received a standard high-energy enteral formula. The incidence of nosocomial infections and mortality, and the consumption of multiple ICU resources were examined. A cost analysis based on these results was then performed to determine the cost effectiveness of this proprietary immunonutrition enteral formula. A pronounced reduction in nosocomial pneumonia (12% vs 52%, p < .01) was identified, with consequent trends toward a reduction in duration of mechanical ventilation and ICU length of stay. Urinary tract infections that may have less influence on ICU resources were increased in the Impact 1.5 group. No difference in mortality was identified, despite the inclusion of patients with severe sepsis in the study group. According to the average number of ICU days required for each study cohort, the Impact 1.5 group led to a cost savings of at least $193,350.00. ICU patients with significant illness severity experienced a decrease in the incidence of an important nosocomial infection that is commonly associated with increased use of ICU resources and length of stay. This decrease in patient morbidity led to substantial cost savings despite the small size of our study trial.

Consejo nutricional aislado frente a suplemento y consejo nutricionales en pacientes con infección por el virus de la inmunodeficiencia humana

Nutritional intervention is a controversial area. The aim of the study was to compare the influence on nutritional status of nutritional supplementation with a standard polymeric formula as well as nutritional counselling versus isolated nutritional counselling in a group of HIV-infected patients. There were 70 patients, 66 of whom were fully evaluated for each study end point after application of prospectively determined evaluability criteria. Of these, 35 were randomized to group I (standard formula) and 35 were randomized to unsupplemented group II. Group I patients received standard enteral formula (3 cans/day, 250 ml per can). Patients were submitted to a prospective serial assessment of their nutrition status (anthropometric and biochemical status) and the nutritional intake was determined by means of 24-hours written food records. Determinations were performed at baseline and at 3 months. Treatment with oral supplements in group I resulted in a significant and sustained increase in weight (2.75%; p < 0.05) which was mostly due to fat mass (10.8%; p < 0.05). In contrast, no changes were detected in group II patients. The increase in body weight and tricipital skinfold was significant in group I. Total body water and fat free-mass remained without changes. CD4 counts and viral load remained stable in both groups. Oral nutritional supplements for a 3-months period resulted in body weight gain in HIV-infected patients, increasing the fat mass. An isolated nutritional counselling did not result in such an increase.

Nutritional Approach in Malnourished Surgical Patients: A Prospective Randomized Study

Hypothesis: Perioperative administration of a supplemented enteral formula may decrease postoperative morbidity. Design: Randomized clinical trial. Setting: Department of surgery at a university hospital. Patients: One hundred ninety‐six registered malnourished patients (weight loss &gt; or = 10%) who were candidates for major elective surgery for malignancy of the gastrointestinal tract. Intervention: After randomization (n = 150), one group received postoperative enteral feeding with a standard diet within 12 hours of surgery (control group; n = 50). Another group orally received 1 L/d for 7 consecutive days of a liquid diet enriched with arginine, omega‐3 fatty acids, and RNA (preoperative group; n = 50). After surgery, patients were given the same standard enteral formula as the control group. A third group orally received 1 L/d for 7 consecutive days of the enriched liquid diet. After surgery, patients were given enteral feeding with the same enriched formula (perioperative group; n = 50). Main Outcome Measures: Postoperative complications and length of hospital stay. Results: The 3 groups were comparable for baseline demographics, biochemical markers, comorbidity factors, and surgical variables. The intent‐to‐treat analysis showed that the total number of patients with complications was 24 in the control group, 14 in the preoperative group, and 9 in the perioperative group (p = .02, control group versus perioperative group). Postoperative length of stay was significantly shorter in the preoperative (13.2 days) and perioperative (12.0 days) groups than in the control group (15.3 days) (p = .01 and p = .001, respectively, versus the control group). Conclusion: Perioperative immunonutrition seems to be the best approach to support malnourished patients with cancer.

Dangers of growth hormone therapy in critically ill patients.

Prolonged length of stay is the major challenge for modern intensive care because of the associated morbidity and the impact on resource utilization. Severe trauma or infection is associated with a catabolic response, which is characterized by increased protein turnover and negative nitrogen balance. Severe catabolism leads to end-organ dysfunction and muscular weakness, prolonging the need for mechanical ventilation. Catabolism cannot be prevented with standard parenteral or enteral nutritional formulas. In order to prevent the complications of catabolism in intensive care patients, recombinant growth hormone has been applied as an experimental therapy for two decades in patients requiring parenteral nutrition and in patients with respiratory failure. Administration of recombinant growth hormone has resulted in positive nitrogen balance, and studies in mechanically ventilated patients suggest that it may shorten the need for ventilatory support. In contrast to the results of these relatively small studies, a recent multinational randomized controlled trial revealed that the administration of recombinant growth hormone (with doses 10-20 times higher than used for replacement therapy) increases mortality of critically ill patients. The excessive mortality in patients treated with recombinant growth hormone was related to infections and development of multiple organ failure, leading to the conclusion that administration of high doses of recombinant growth hormone cannot be recommended for critically ill patients. This review reinforces that conclusion.

Dangers of growth hormone therapy in critically ill patients

Prolonged stay of patients is the major challenge for modern intensive care because of its effects on morbidity and resource utilization. Severe trauma or infection are associated with the catabolic response, characterized by increased protein turnover and negative nitrogen balance. Severe catabolism leads to end-organ dysfunction and muscular weakness prolonging the need for mechanical ventilation. Catabolism cannot be prevented with standard parenteral or enteral nutritional formulas. In order to prevent the complications of catabolism in intensive care patients, recombinant growth hormone (rhGH) has been applied during two decades as an experimental therapy for patients requiring parenteral nutrition and for those with respiratory failure. Administration of rhGH has resulted in positive nitrogen balance, and studies in mechanically ventilated patients suggest that it may shorten the need for ventilatory support. In contrast to the results of these relatively small studies, a recent multinational randomized controlled trial revealed that the administration of rhGH (with doses 10-20 times higher than those used for replacement therapy) increases the mortality of critically ill patients. This excessive mortality in patients treated with rhGH was related to infections and development of multiple organ failure. Administration of high doses of rhGH to critically ill patients cannot thus be recommended.

Whole-protein-based enteral formula stimulates intestinal ornithine decarboxylase activity more than single amino acids but does not affect mucosal adenosine triphosphate content in early postsurgical refeeding.

To restore intestinal integrity after starvation and trauma, luminal nutrients are essential. Specific nutrients such as glutamine support mucosal proliferation and energy metabolism. The aim of this study was to compare effects of enteral formula vs specific amino acids on ornithine decarboxylase (ODC) activity and adenine nucleotide metabolism in jejunal mucosa. Male Wistar rats (240 to 280 g) were starved for 48 hours and subjected to intestinal transection, gastrotomy, and jejunal instillation of 5mL nutrient solution. In the first experiment, standard enteral formula (EF) was compared with isonitrogenous formula supplemented with the glutamine precursor, alpha-ketoglutarate (alpha-KG). In a second experiment, 2% glutamine was compared with isonitrogenous ornithine alpha-KG, arginine alpha-KG, glycine and diluted standard enteral formula (EF), or saline. The ODC activity, adenosine triphosphates (ATP), and RNA and protein in the jejunal mucosa were analyzed 2 hours after surgery. The ODC peak in jejunal mucosa in animals treated with EF was higher than when supplemented with alpha-KG (p < .05). Compared with specific amino compounds, EF resulted in a significantly higher ODC peak and no differences were seen between the different specific amino acids. Differences seen in ATP or energy charge between the groups were not significant. Immediate postoperative enteral feeding by standard EF results in rapid increase of ODC activity. This response was attenuated when the enteral nutrition was supplemented with alpha-KG and was absent when isonitrogenous single amino acids were administered. We found no significant effects on ATP content in the small bowel mucosa by supplementing the diet with alpha-KG.