bluuebunny/crossref_metadata_2025 huggingface dataset:
Unclogging feeding tubes with pancreatic enzyme
Authors: Marcuard SP , Stegall KS
Published: May 2008

Occlusion of small‐bore feeding tubes (Dobbhoff, 8 French) was observed at our institution in 32 of 90 patients (35%) over an 8‐month period. The purpose of this study was to evaluate possible causes of tube occlusion and to assess the efficacy of an activated pancreatic enzyme solution to clear obstructed feeding tubes. A Drum cartridge catheter was inserted into the occluded feeding tube to displace any liquid formula and to apply the enzyme solution close to the obstruction site. Water was injected first and served as control. The feeding tubes of 32 patients occluded 60 times during an 8‐month period and declogging was attempted in 44 instances. Water was able to clear the obstruction in 12 cases. In the remaining 32 cases, the activated pancreatic enzyme was injected, and the obstruction was cleared in 23 cases (72%). The causes of failure to clear the obstruction were determined in seven cases: tablet impaction (three cases), knotted feeding tube (two cases), tomato seed occluded the feeding port (one case), formula clot in two‐third length of the tube for 24‐hr (one case). Thus, the pancreatic enzyme solution was successful in restoring tube patency in 23 of 24 instances (96%) where formula clotting was the likely cause of occlusion and Coke or water had failed.
Treatment of acid maltase deficiency with a diet high in branched‐chain amino acids
Authors: Mobarhan S , Pintozzi RL , Damle P , Friedman H
Published: May 2008

Acid maltase deficiency in adults is associated with progressive muscle weakness and may effect respiratory muscles resulting in respiratory failure. The biochemical and clinical manifestations of acid maltase deficiency arise from a marked deficiency of the lysosomal enzyme alpha‐glucosidase (acid maltase), which normally degrades glycogen to free glucose. In the past few years, high‐protein diets have provided an alternative energy source for these patients and resulted in improved muscle strength. Recently, we treated a ventilator‐dependent acid maltase‐deficient patient with a general diet supplemented with branched‐chain amino acids. Branched‐chain amino acids are the principal amino acids involved in muscle protein synthesis and utilization. While on this diet, the patient had improvement of respiratory function and muscle strength and was able to be weaned from the ventilator during the day. In addition to his nutritional status, levels of serum branched‐chain amino acids, showed improvement within 2 months after the diet started. This diet shows potential advantages over a high‐protein diet without supplemented branched‐chain amino acids for the treatment of acid maltase deficiency. These include theoretical sparing of amino acids required for muscle protein synthesis by providing higher concentrations of postprandial branched‐chain amino acids in the circulation. Also, the liquid formula would be better tolerated by a ventilator‐dependent or debilitated patient rather than a high‐protein general diet. Further experience with branched‐chain amino acid formulas will be needed to substantiate their efficacy in the treatment of acid maltase deficiency.
Feeding the Rat Intravenously with Ketone Bodies following Colon Anastomosis
Authors: Nagayama Masayoshi , Thomford Neil R. , Birkhahn Ronald H.
Published: May 2008

Ketone bodies are an important metabolic fuel for the gastrointestinal system and as a consequence may promote colonic healing. Ketone bodies and glucose were compared in a dose dependent manner as nonprotein fuels for support of resected colon. Rats had their descending colons resected and received all nutrients by vein for 5 days postoperation. Colonic healing was evaluated from the air pressure required to break the wound. All rats received constant nutrients except for non‐protein energy which was fed at 10.5, 21, 31.5, and 42 kcal/day using either glucose or monoacetoacetin as substrate. Colonic bursting pressure was measured on day 5 after surgery. When energy intake was 21 kcal/day or greater, the bursting pressure was two‐thirds of nonwounded tissue and was independent of energy quantity and source. At 10.5 kcal/ day, bursting pressure for glucose‐fed animals was similar to that for animals with no added nonprotein energy while, in contrast, bursting pressure for animals fed monoacetoacetin was similar to that for animals fed 42 kcal/day. It was concluded that bursting pressure was influenced by dietary intake only if the energy intake was sufficiently low, and then ketone bodies were better than glucose for support of colonic healing. (Journal of Parenteral and Enteral Nutrition 14:245–249, 1990)
Stability of Imipenem and Cilastatin Sodium in Total Parenteral Nutrient Solution
Authors: Zaccardelli David S. , Sanders Krcmarik Claudia , Wolk Robert , Khalidi Nabil
Published: May 2008

The chemical stability and compatibility of imipenem‐cilastatin sodium (Primaxin) in two different total parenteral nutrient (TPN) solutions was determined. TPN solutions consisted of 4.25% and 5% amino acids with 25% and 35% dextrose, respectively.

Imipenem‐cilastatin sodium was constituted with 10 ml of sterile water and admixed with 90 ml of TPN solution for a final concentration of 5 mg/ml of each drug. The final solutions were assayed at times 0 (immediately after admixture), 15 min, 30 min, 1, 4, 8, and 24 hr by a stability‐indicating high‐performance liquid chromatographic assay. Concurrently, test TPN solutions were monitored for pH changes, color changes, and precipitate formation. The potential effect of imipenem‐cilastatin sodium on the stability of amino acids and other TPN additives was not evaluated.

Imipenem and cilastatin sodium was stable (≥90% recovered) in each TPN solution at 15 min. A significant (≥10%) and steady decrease of imipenem recovery occurred at subsequent sampling times. Cilastatin appeared more stable than imipenem in both TPN solutions. A physical color change from colorless to dark orange appeared in each TPN solution over the 24‐hr study period.

Imipenem‐cilastatin sodium is stable for 15 min in the TPN solutions studied; however, until the stability of the amino acids can be determined, the antibiotic should be administered through a separate line or Y‐site while the TPN infusion is interrupted. (Journal of Parenteral and Enteral Nutrition 14:306–309, 1990)
Optimum Branched‐Chain Amino Acids Concentration for Improving Protein Catabolism in Severely Stressed Rats
Authors: Kawamura Isao , Yamazaki Kazuma , Tsuchiya Hiroaki , Miyazawa Yukimasa , Isono Kaichi , Akiyama Tadashi , Higashino Hiroshi , Okamoto Mitsuru
Published: May 2008

In this study, an experiment was performed to investigate the optimal concentration of branched chain amino acid (BCAA) in hyperalimentation to be administered when protein catabolism is accelerated by sepsis or bodily injury. Amino acid solutions containing BCAA 25%, 30%, 40%, 45% and 50% were prepared and were administered iv for three days with other essential amino acid‐containing nitrogen in the same volume into rats with peritonitis which had been developed by ligature and puncture at the cecum, and the results were compared. After observing for three days, the influence over nitrogen balance, improvement of 3‐methyl‐histidine/creatinine in urine, weight loss in muscles, and aminogram in serum and muscles indicated that the hyperalimentation under stress is utilized most effectively when amino acid contains 45% of branched‐chain amino acid. (Journal of Parenteral and Enteral Nutrition 14:398–403, 1990)
Enteral Nutrition in Anorexia Nervosa
Authors: Bufano Giovanni , Bellini Carlotta , Cervellin Gianfranco , Coscelli Carlo
Published: May 2008

Biochemical and anthropometric data were collected in 9 subjects with anorexia nervosa before and after enteral nutrition by the nasogastric route. All subjects but one accepted the treatment which was stopped as soon as an adequate spontaneous food intake was resumed. Enteral nutrition caused a significant increase of mid‐arm muscle circumference and of tricipital skinfold. Body weight gain was remarkable, averaging a rate of 8.22 kg/month. This value was not different from the levels attained by anorectic subjects put on total parenteral nutrition. Furthermore, a significant rise of some biochemical indexes, namely prealbumin and total iron binding capacity, was achieved. The most impressive drawbacks of enteral nutrition were occasional hypophosphatemia and moderate rise of serum aspartate and alanine aminotransferases. Both of these abnormalities were transient and apparently not associated with clinical disturbances. (Journal of Parenteral and Enteral Nutrition 14:404–407, 1990)
Effect of Tracer and Intravenous Fat Emulsion on the Measurement of Reticuloendothelial System Function
Authors: Hirschberg Yulia , Pomposelli James J. , Mascioli Edward A. , Bistrian Bruce R. , Blackburn George L.
Published: May 2008

Since the addition of lipid to intravenous feeding formulas, animal and human studies have shown impairment of the reticuloendothelial system (RES) due to slow rates of clearance and gradual accumulation of long chain triglycerides (LCT) in the liver. Medium chain triglycerides (MCT) accumulate only minimally in the liver and do not impair the RES. However, results from animal studies using technetium sulfur colloid (TSC) to assess RES function have been inconclusive. The present study reevaluates RES function after lipid infusion in guinea pigs as measured by organ distribution of TSC. Guinea pigs were fed 300 kcal/kg/day of total parenteral nutrition (TPN) for 2.5 days, with 50% of nonprotein calories as fat in the form of LCT or MCT, then injected intravenously with 2.5 or 25 μCi of TSC, and uptake by liver, spleen, and lungs was determined. Liver, lungs, and spleen all increased in size after TPN with LCT or MCT. Liver TSC uptake was significantly affected by the dose of TSC (p < 0.05), with the high dose probably inducing an increased capacity of the liver to clear TSC from the blood. Liver uptake was not influenced by diet, but feeding MCT did significantly stimulate lung uptake of TSC (p < 0.0001). This suggests that the hepatic TSC uptake system is not saturable, and may not be an appropriate measure of Kupffer cell function since the colloid is not phagocytosed. However, TSC blood clearance remains an excellent prognostic indicator for bacteremia and mortality in humans, and is useful for measuring global RES function. (Journal of Parenteral and Enteral Nutrition 14:463–466, 1990)
Preincubation with Intravenous Lipid Emulsion Reduces Chemotactic Motility of Neutrophils in Cord Blood
Authors: Kohelet David , Peller Shoshana , Arbel Eliana , Goldberg Michael
Published: May 2008

Neutrophils from cord blood of healthy term infants were isolated and incubated for 30 min with varying concentrations of intravenous lipid emulsion (ILE) solution (4, 8, 20 mg/ml). In vitro assay of chemotaxis was performed after incubation for 120 min with endotoxin‐activated serum (EAS). Neutrophil random motility was unchanged after ILE incubation yet chemotactic factor (EAS)‐stimulated motility was significantly reduced in a dose‐related pattern. (Journal of Parenteral and Enteral Nutrition 14:472–473, 1990)
Superior Vena Caval Obstruction in Patients with Gut Failure Receiving Home Parenteral Nutrition
Authors: Beers T.R. , Burnes J. , Fleming C.R.
Published: May 2008

Clinical suspicion and venographic conformation were used to diagnose 15 cases of superior vena caval obstruction (SVCO) in 107 home parenteral nutrition (HPN) patients over 379 cumulative years of HPN (3.9 cases/100 patient‐years). Patients with SVCO had been on HPN a mean of 51.5 months and had used 6.2 (range 1–50) central catheters, including short‐ and long‐term, before SVCO was diagnosed. The frequency of inflammatory bowel disease (IBD) with SVCO was approximately the same as that in our general HPN population. Positive blood cultures were present immediately preceding the diagnosis of SVCO in 40% (six of 15) of cases. Atypical line placements were noted in two cases. The most common management strategies employed were conversion to enteral feedings in five patients and placement of a new catheter directly into the right atrium by thoracotomy in another five patients. Two of the five with right atrial catheters experienced a postpericardiotomy syndrome (fever, pericardial rub, and pulmonary infiltrates) that responded promptly to indomethacin. The most significant long‐term sequela of SVCO was the need for a left jugular vein to right atrial appendage bypass in one patient with chronic venous congestion from her SVCO. Once the SVCO is confirmed, systemic heparinization provides immediate antithrombotic effect and minimizes the risk of pulmonary embolism. The use of streptokinase may result in rapid thrombolysis. (Journal of Parenteral and Enteral Nutrition 14:474–479, 1990)
Cardiac Tamponade and Hydrothorax as Complications of Central Venous Parenteral Nutrition in Infants
Authors: Giacoia George P.
Published: May 2008

The recent use of soft catheters made of silastic polymeric silicone or polyurethane has decreased the incidence of perforation of great veins or right‐sided heart chambers but has not eliminated it as had been hoped. Two premature infants who presented with cardiac tamponade more than 24 hr after the insertion of a 23‐gauge silastic catheter for total parenteral nutrition (TPN) administration are described. In one infant, bilateral hydrothorax preceded the occurrence of cardiac tamponade. Osmotic injury to great vessels and/or myocardium seems to be the common mechanism but which these complications of intraluminal catheters are produced. Review of the pediatric literature revealed a proportion of low birth weight infants among the reported cases. Despite a prohibitively high mortality rate, early recognition can prevent a fatal outcome. (Journal of Parenteral and Enteral Nutrition 15:110–113,1991)
Effect of a Taurine‐Supplemented Diet on Conjugated Bile Acids in Biliary Surgical Patients
Authors: Wang Wen‐Yen , Liaw Koung‐Yi
Published: May 2008

The effect of a taurine‐supplemented diet on the level of conjugated bile acids in postoperative patients was investigated during two consecutive 5‐day periods. Eighteen hepatobiliary patients with choledochostomies and a specific T‐tube insertion were collected and divided randomly into two groups. In group 1, an ordinary postoperative soft diet was prescribed for the first 5 postoperative days and then followed with a taurine‐supplemented soft diet (40 μmol/kg per day) for 5 consecutive days. In group 2, the taurine‐supplemented diet was prescribed in reverse. At the end of the two periods, on days 5 and 10, bile was collected via a T‐tube with an inflatable balloon and low‐pressure motor suction. Analysis of conjugated bile acids was done by high‐performance liquid chromatography. The results showed that a taurine‐supplemented diet increased the concentration of taurocholic acid, glycocholic acid, taurochenodeoxycholic acid, glycochenodeoxycholic acid, and total bile acid from 0.5, 1.9, 0.3, 1.4, and 4.7 mg/mL (on day 5) to 1.1, 3.5, 1.0, 2.6, and 8.9 mg/mL, respectively, on day 10 in group 1. Similar findings were noted in group 2. These results indicate that a taurine‐supplemented diet may enhance the conjugation and secretion of bile acid in hepatobiliary patients. (Journal of Parenteral and Enteral Nutrition 15:294–297, 1991)
Lack of Predictive Value of the APACHE II Score in Hypoalbuminemic Patients
Authors: Pollak Arnold J. , Strong Richard M. , Gribbon Rita , Shah Himanshu
Published: May 2008

The APACHE II score predicts mortality in severely ill patients. This score does not account for the serum albumin level. Ninety‐three patients (28 with serum albumin levels <2.5 g/dL [group I] and 65 with serum albumin levels ≥2.5 [group II]) were retrospectively reviewed. Patients were comparable in age, APACHE II score, and compliance with required protein needs. Patients with severe hypoalbuminemia had nearly double the death rate of patients with mildly low or normal albumin concentrations (54% compared with 29%). The death rate in the severely hypoalbuminemic patients was 5.1‐fold higher than would be predicted by their APACHE II score. The death rate in those patients with mildly low or normal albumin levels had only a 1.9‐fold higher rate than would be predicted by their APACHE II score. It is concluded that severe hypoalbuminemia increases the risk of death significantly higher than would be predicted by the APACHE II score. APACHE II score is not as accurate in a severely hypoalbuminemic population. (Journal of Parenteral and Enteral Nutrition 15:313–315, 1991)
Obligatory Negative Nitrogen Balance Following Spinal Cord Injury
Authors: Rodriguez Donna J. , Clevenger Frederick W. , Osler Turner M. , Demarest Gerald B. , Fry Donald E.
Published: May 2008

Obligatory nitrogen losses due to paralysis in the spinal cord‐injured (SCI) patient prevent positive nitrogen balance (NB) regardless of the calorie and protein intakes. Ten patients with SCI and 20 controls with nonspinal cord injury (NSCI) matched for time, sex, age, and injury severity score (ISS) were admitted to our Level I trauma center. In both groups, total nutritional support was delivered within 72 hours of admission based on predicted energy expenditures (PEE = Harris‐Benedict equation x 1.2 x 1.6) and 2 g of protein/kg of ideal body weight (IBW). Subsequent changes in nutrient delivery were based on NB. No SCI patient established positive NB during the 7‐week period following injury despite an average delivery of 2.4 g of protein/kg IBW and 120% of the PEE at the time of peak negative NB (‐10.5). In six SCI patients, an average increase of 25% in delivered protein and 12% in delivered calories over a 1‐week period effected no change in average NB (‐7.4 us ‐6.8). Indirect calorimetry in five SCI patients showed that calorie intakes were 110% more than average measured energy expenditures. In contrast, 17 of 20 NCSI patients achieved positive NB within 3 weeks of admission. They required an average delivery of 2.3 g of protein/kg IBW and 110% of PEE to reach positive NB. These data demonstrate the phenomenon of obligatory negative NB acutely following SCI. Aggressive attempts to achieve positive NB in these patients will fail and result in overfeeding. (Journal of Parenteral and Enteral Nutrition 15:319–322, 1991)
Empirical Assessment of Model Validity
Authors: Wolfe Robert R.
Published: May 2008

The metabolism of amino acids is far more complicated than a 1‐ to 2‐pool model. Yet, these simple models have been extensively used with many different isotopically labeled tracers to study protein metabolism. A tracer of leucine and measurement of leucine kinetics has been a favorite choice for following protein metabolism. However, administering a leucine tracer and following it in blood will not adequately reflect the complex multi‐pool nature of the leucine system. Using the tracer enrichment of the ketoacid metabolite of leucine, a‐ketoisocaproate (KIC), to reflect intracellular events of leucine was an important improvement. Whether this approach is adequate to follow accurately leucine metabolism in vivo or not has not been tested. From data obtained using simultaneous administration of leucine and KIC tracers, we developed a 10‐pool model of the in vivo leucine‐KIC and bicarbonate kinetic system. Data from this model were compared with conventional measurements of leucine kinetics. The results from the 10‐pool model agreed best with the simplified approach using a leucine tracer and measurement of KIC enrichment. (Journal of Parenteral and Enteral Nutrition 15:505–545, 1991)
Incorporating Tracer‐Tracee Differences into Models to Improve Accuracy
Authors: Schoeller Dale A.
Published: May 2008

The ideal tracer for metabolic studies is one that behaves exactly like the tracee. Compounds labeled with isotopes come the closest to this ideal because they are chemically identical to the tracee except for the substitution of a stable or radioisotope at one or more positions. Even this substitution, however, can introduce a difference in metabolism that may be quantitatively important with regard to the development of the mathematical model used to interpret the kinetic data. The doubly labeled water method for the measurement of carbon dioxide production and hence energy expenditure in free‐living subjects is a good example of how differences between the metabolism of the tracers and the tracee can influence the accuracy of the carbon dioxide production rate determined from the kinetic data. (Journal of Parenteral and Enteral Nutrition 15:64S‐67S, 1991)
Role of Modeling in the Design of Experiments in Carbohydrate Metabolism
Authors: Foster David M. , Hetenyi Geza
Published: May 2008

Most publications on modeling present only the final product without describing the details as to how they were developed and tested. It is, however, by model development and testing that the true power of modeling as a research tool reveals itself. The purpose of this paper is to present a “behind the scenes” look at a set of experiments designed to study carbon atom transport in gluconeogenesis. In particular, it will be shown how the development of one model led to hypotheses for which another set of experiments was designed. The model which resulted from the second study contained in turn a number of new hypotheses for which further experiments remain to be designed. The second model supported the findings of the first, and yielded deeper insights into the exchange of carbon atoms among three metabolites. It is hoped this illustration will encourage other investigators to take advantage of the utilitarian value of modeling not only as a parameter generating tool, but also as a true research tool which can aid significantly to extract more information from available data. (Journal of Parenteral and Enteral Nutrition 15:67S‐71S, 1991)
Noninvasive Approaches to Tracing Pathways in Carbohydrate Metabolism
Authors: Landau Bernard R.
Published: May 2008

Compounds that can be given safely in large quantity, conjugate with intermediates of carbohydrate metabolism in liver, and are then excreted, allow large amounts of those intermediates to be isolated noninvasively. By administering labeled compounds that form those intermediates and determining the amount and/or distribution of label in those intermediates, the metabolism of those compounds can be traced. Thus, glucuronide formation has been used to sample hepatic uridine diphosphate glucose (UDP‐glucose) and study glycogen metabolism and the pentose pathway, phenylacetate to sample hepatic α‐ketoglutarate and estimate relative flux through the Krebs cycle, and acetylation to sample hepatic acetyl CoA. Interpretations require knowledge of the anatomical sites of formation of the intermediates, since more than one pool of an intermediate can exist in liver. The extent the labeled compound is metabolized in extrahepatic tissues also must be taken into account. (Journal of Parenteral and Enteral Nutrition 15:74S‐77S, 1991)
The Liver and Glycogen Metabolism
Authors: Radziuk Jerry
Published: May 2008

It was shown that the liver is not the major site of removal of glucose after a carbohydrate meal in man. Fractional extractions varied from 5 to 10%. Alternative substrates for postprandial hepatic glycogen synthesis were therefore sought. It was demonstrated that, in man, about 60% of hepatic glycogen was formed from gluconeogenetic substrates. Since significant excursions occur only in plasma lactate after glucose loading, this was deemed the most likely substrate under these circumstances. By differential sampling across the liver and the gut in a conscious pig model, it was found that the liver takes up enough lactate (fractional extraction of 40–50%) to account for the gluconeogenetic production of glycogen. Forty percent of this arises from the gut. Muscle (as represented by the forearm in man) does not contribute lactate during glucose loading, suggesting that other tissues such as the skin are of importance. The gluconeogenetic process may be an important site for the obligatory tissue production of lactate. (Journal of Parenteral and Enteral Nutrition 15:77S‐81S, 1991)
Leucine Metabolism in Man: Lessons from Modeling
Authors: Matthews Dwight E. , Cobelli Claudio
Published: May 2008

The metabolism of amino acids is far more complicated than a 1‐ to 2‐pool model, yet, such simple models have been extensively used with many different isotopically labeled tracers to study protein metabolism. A tracer of leucine and measurement of leucine kinetics has been a favorite choice for following protein metabolism. However, administering a leucine tracer and following it in blood will not adequately reflect the complex, multi‐pool nature of the leucine system. Using the tracer enrichment of the ketoacid metabolite of leucine, α‐ketoisocaproate (KIC), to reflect intracellular events of leucine was an important improvement. Whether this approach is adequate to follow accurately leucine mtabolism in vivo or not has not been tested. From data obtained using simultaneous administration of leucine and KIC tracers, we developed a 10‐pool model of the in vivo leucine‐KIC and bicarbonate kinetic system. Data from this model were compared with conventional measurements of leucine kinetics. The results from the 10‐pool model agreed best with the simplified approach using a leucine tracer and measurement of KIC enrichment. (Journal of Parenteral and Enteral Nutrition 15:865–895, 1991)
Survival in Septic Guinea Pigs Is Influenced by Vitamin E, but Not by Vitamin C in Enteral Diets
Authors: Peck Michael D. , Alexander J. Wesley
Published: May 2008

Oxygen‐free radicals are produced during sepsis, and may contribute to cell injury and dysfunction. We studied the effect of different levels of vitamins E and C in the diet fed enterally to septic guinea pigs. Sixty‐four female guinea pigs were provided with gastrostomies and allowed to recover. Intraperitoneal osmotic pumps were then implanted that provided effusion of Escherichia coli and Staphylococcus aureus for the next 7 days. Three days after pump implantations, the animals were started on one of nine diets. The diets were isocaloric and isonitrogenous, and differed only in the amounts of vitamins E and C. Three levels of each vitamin were used, based on the Recommended Daily Allowance (RDA). The feedings were continued for 2 weeks, during which time mortality was observed. The amount of vitamin C had no effect on outcome, with mortality rates of 68% (15/22) in the 1 x RDA group, 73% (16/22) in the 5 x RDA group, and 65% (13/20) in the 25 × RDA group. However, vitamin E altered outcome significantly, with mortality rates of 86% (18/21) in the 1 x RDA group, 45% (10/22) in the 3 x RDA group, and 76% (16/21) in the 9 x RDA group. Mortality in the 3 x RDA group was significantly lower than that in the 1 × RDA group and in the 9 × RDA group. We conclude that supplemental vitamin C has no effect on outcome in this model. However, survival in guinea pigs with peritonitis appears to be sensitive to the amount of vitamin E in the diet. We conjecture that low levels of vitamin E may be inadequate to protect against lipid peroxidation during sepsis. (Journal of Parenteral and Enteral Nutrition 15:433–436, 1991)
Determination of the Fiber Content of Enteral Feedings
Authors: Fredstrom Susan B. , Baglien Kim S. , Lampe Johanna W. , Slavin Joanne L.
Published: May 2008

The importance of dietary fiber in maintaining optimum bowel function has been shown in feedings studies, and many enteral formulas now contain dietary fiber, usually as soy polysaccharide (SP). Generally only total dietary fiber (TDF) values are given on the label or in product literature, with no indication of insoluble dietary fiber (IDF) and soluble dietary fiber (SDF) content. Often product literature highlights the amount of SP contained in the formula, not the TDF. The method used to determine TDF content usually is not specified, making it impossible to compare products on a TDF basis. We compared the dietary fiber content of commercially available enteral formulas objectively to help clinicians make informed choices when selecting fiber‐containing formulas. Fiber‐containing formulas by suppliers were freeze‐dried and total, watersoluble, and water‐insoluble dietary fiber measured by the Association of Official Analytical Chemists (AOAC) approved method. TDF per 1000 mL ranged from 4.0 to 9.9 g for blenderized formulas and from 7.2 to 20.3 g in formulas containing SP. IDF values per 1000 mL ranged from 2.0 to 5.4 g for blenderized product, and the soy formulas ranged from 5.5 to 16.9 g. SDF values per 1000 mL ranged from 2.0 to 4.5 g in blenderized products, and in soy formulas SDF ranged from 1.7 to 3.8 g. Differences in physiological effects of fiber‐containing enteral formulas may be because of differences in fiber composition. (Journal of Parenteral and Enteral Nutrition 15: 450–453, 1991)
A Case of Intracerebral Air Embolism Secondary to the Insertion of a Hickman Line
Authors: Dilkes M.G. , Dunwoody G. , Bull T.M. , Eppel B. , Barrett N.J.
Published: May 2008

Complications following the insertion of intravenous catheters are relatively uncommon. We report a potentially serious, hitherto unrecognized complication of Hickman line insertion, and discuss the condition. (Journal of Parenteral and Enteral Nutrition 15:488–490, 1991)
Effect of Glutamine Infusions on Glutamine Concentration and Protein Synthetic Rate in Rat Muscle
Authors: Wusteman Monica , Elia Marinos
Published: May 2008

Studies were undertaken in sedated and unsedated rats to raise the depleted intramuscular glutamine concentrations produced by aseptic abscesses, and to assess the effect of this change on muscle protein fractional synthetic rate. Age‐ and weight‐matched control animals were also included in the study.

The rats were infused for up to 5 hours via the lateral tail vein with 1 mL/100 g of body weight per hour of either saline or 0.22 M glutamine. The intramuscular concentration of glutamine (mmol/L of intracellular water), which was reduced by 45% after turpentine in the sedated animals, was restored to within 79% of control values, but the muscle fractional protein synthetic rate, which was also reduced by 41% in these animals, was not improved by the glutamine infusions. Glutamine administration also failed to increase muscle protein synthesis in unsedated rats and in those supplemented with a liquid meal.

It is concluded that acute elevations in muscle glutamine concentrations do not increase protein synthesis in this tissue and that therefore glutamine is unlikely to be a mediator in the control of muscle protein synthesis under these circumstances. (Journal of Parenteral and Enteral Nutrition 15:521–525, 1991)
Increased Lipoprotein X Causes Hyperlipidemia During Intravenous Administration of 10% Fat Emulsion in Man
Authors: Tashiro Tsuguhiko , Mashima Yoshiya , Yamamori Hideo , Horibe Kazuo , Nishizawa Masahiko , Sanada Masao , Okui Katsuji
Published: May 2008

To clarify the mechanisms of hyperlipidemia during intravenous Intralipid 10%, lipoprotein profiles including lipoprotein X were studied in 13 patients receiving 2.0 g of fat per kilogram per day by Intralipid 10% over a period of 8 weeks. All patients were fed exclusively by total parenteral nutrition providing 1.1 g of amino acid and 30 kcal/kg per day. Intravenous administration of Intralipid 10% caused a marked increase of low‐density lipoprotein (LDL), phospholipid, and cholesterol, especially free cholesterol, whereas triglyceride, very‐low‐density lipoprotein, and high‐density lipoprotein remained within the normal range. Lipid composition of LDL approximated that of lipoprotein X progressively with the intravenous Intralipid 10%. Quantification of lipoprotein X revealed that its increase was proportionate with that of LDL and total lipid. From these findings, hyperlipidemia during intravenous Intralipid 10% is induced almost exclusively by the increased lipoprotein X. (Journal of Parenteral and Enteral Nutrition 15:546–550, 1991)
Effect of a Lactase Preparation on Lactose Content and Osmolality of Preterm and Term Infant Formulas
Authors: Carlson Susan J. , Rogers Ron R. , Lombard Kenneth A.
Published: May 2008

Lactose intolerance due to lactase deficiency often follows acute gastroenteritis. In such situations, a lactose‐free formula may be indicated for preterm infants. Therefore, the effect of addition of lactase on the lactose content and osmolality of preterm and term infant formulas was studied. Lactose content of formulas at room temperature was decreased by approximately 50% 1 hour after addition of lactase. Concentration of lactose was reduced by 70% or more after 2 hours in all formulas. Because of the higher initial lactose concentration in term formulas, it took 24 hours to reach the same absolute lactose concentration (10 g/kg formula) found in preterm formulas after 2 hours. There was a moderate increase in osmolality in preterm formulas. The increase was greater in term formulas because of the greater initial concentration of lactose. The addition of lactase appears to be a suitable method for reduction of lactose content of preterm and term formulas, although the increase in osmolality of term formulas may preclude their clinical use. (Journal of Parenteral and Enteral Nutrition 15:564–566, 1991)
Optimal Ratio of Individual Branched‐Chain Amino Acids in Total Parenteral Nutrition of Injured Rats
Authors: Iwasawa Yasuo , Kishi Tetsuya , Morita Motoyo , Ikeda Keiko , Shima Hideaki , Sato Tadashi
Published: May 2008

In this study, we investigated the optimal ratio of individual branched‐chain amino acids (BCAA) in a balanced amino acid infusion in laparotomized rats. The total BCAA contents of four amino acid infusions were fixed at 31% of total amino acids. The weight ratios of individual BCAA (isoleucine:leucine:valine) in the solutions were 1:0.5:1, 1:1:1, 1:2:1, and 1:4:1, respectively. The laparotomized rats were infused with about 140 mg (experiment 1) and 100 mg (experiment 2) of nitrogen and 10 g of glucose daily for 7 days. In both experiments, no marked difference was observed in the mean cumulative 7‐day nitrogen balance and the urinary 3‐methylhistidine levels of all the groups. The BCAA concentrations and the molar ratios of individual BCAA in plasma were disarranged by the infusion of the 1:0.5:1 and 1:4:1 solutions. The infusion of the 1:1:1 and 1:2:1 solutions tended, however, to allow the values to approach the preinfusion values. These results suggest that the optimal ratio of individual BCAA in an amino acid infusion lies between 1:1:1 and 1:2:1 for this injured rat model in total parenteral nutrition. (Journal of Parenteral and Enteral Nutrition 15:612–618, 1991)
Evaluation of the Predictive Performance of Nutritional Indicators by Receiver‐Operating Characteristic Curve Analysis
Authors: Braga M. , Gianotti L. , Radaelli G. , Cristallo M. , Baccari P. , Dal Cin S. , Di Carlo V.
Published: May 2008

Four hundred twenty‐two cancer patients who underwent major surgery were studied. At admission, nutritional status was evaluated in all patients by assessing serum albumin (SA), total iron‐binding capacity (TIBC), total lymphocyte count (TLC), serum cholinesterase activity (CHE), and weight loss (WL). All patients received perioperative short‐term antibiotic prophylaxis and postoperative total parenteral nutrition. Prognostic ability of nutritional indicators was assessed by receiver‐operating characteristic (ROC) curve analysis. The area beneath the ROC curve (Az) is an index of predictor performance when its value ranges from 0.5 (chance performance) to 1 (perfect prediction). Specificity, sensitivity, Youden index, and predictive values were determined for each nutritional parameter within a wide range of potential threshold values. Postoperative septic complications were observed in 85 (20.14%) patients. The Az values for the considered nutritional parameters ranged from 0.52 to 0.57 and that showed the low predictive ability of the parameters. When sensitivity and specificity for each nutritional parameter were examined at different thresholds, a clearly more predictive cutpoint was not observed, but ranges of values with a similar predictivity were observed. Significant ranges of predictivity were found for SA (33 to 35 g/L), for TIBC (2200 to 2300 μg/L), for TLC (2100 to 2200 million/L), for CHE (1700 to 1900 U/L), and for WL (7% to 12%). The higher values of Youden index were as follows: 1.183 for WL (cutoff 11%), 1.150 for TLC (cutoff 2100 million/L), and 1.145 for SA (cutoff 35 g/L). In conclusion, ROC curve analysis showed that the nutritional parameters had a low predictive ability. However, an examination of different thresholds showed that within closed ranges of values the parameters provided a significant prognostic performance. (Journal of Parenteral and Enteral Nutrition 15:619–624, 1991)
Photosensitized Oxidation of Tryptophan: Effect on Liver and Brain Tryptophan
Authors: Bhatia Jatinder , Rassin David K. , Mcadoo David J.
Published: May 2008

Toxic products are formed when tryptophan is irradiated with light in the presence of photosensitizers such as riboflavin. In order to further investigate this phenomenon, solutions of tryptophan (48 μmol·mL−1) were irradiated with broad spectrum fluorescent light in the presence or absence of riboflavin (0.01 mg.mL−1). Solutions of riboflavin were similarly irradiated; control solutions were the respective solutions not exposed to light. Two‐week‐old suckling gerbils were then assigned to receiving 7 days of intraperitoneal injections of the light‐exposed or non‐light‐exposed solutions.

There were significant differences in the concentrations of tryptophan in serum, liver, and brain; activity of gamma‐glutamyl transferase (GGT) as well as liver protein were also significantly different among the groups. Body and liver weights were also significantly different among the groups.

In order to identify the photoproducts responsible for these changes, solutions of tryptophan that had been irradiated with light in the presence of riboflavin were then fractionated based on time of elution during high‐pressure liquid chromatography and the fractions were then injected into the gerbils as before. GGT responses to one of the fractions was similar to that of the parent compound. Chromatographic studies indicated the presence of numerous photoadduct compounds of tryptophan and riboflavin after exposure to light.

Both the presence of riboflavin and the exposure of the solutions to light alter brain concentrations of tryptophan in the developing gerbil indicating differing availability to the brain of this serotonin precursor. Clinical implications of the infusion of amino acids in the presence of photosensitizers and light must be considered. (Journal of Parenteral and Enteral Nutrition 15:637–641, 1991)
Insufficient Effect of Total Parenteral Nutrition to Improve Protein Balance in Peripheral Tissues of Surgical Patients
Authors: Möller‐Loswick Ann‐Charlotte , Zachrisson Helen , Bennegård Klas , Sandström Rolf , Lundholm Kent
Published: May 2008

Previous studies have indicated that unstressed and malnourished patients do not necessarily obtain amino acid balance across peripheral tissues during total parenteral nutrition (TPN) treatment, indicating treatment inefficiency. Therefore, the aim of this study was to evaluate to what extent (prevalence) insufficient therapeutic amino acid balance occurs in surgical patients receiving TPN for standard medical reasons. Thirty‐two patients treated in an ordinary surgical ward (n = 17) or in the intensive care unit (ICU) (n = 15) were examined. The arteriovenous balance across the leg of amino acids, glucose, glycerol, lactate, and oxygen was measured in relationship to plasma levels of insulin. All patients had been receiving TPN for at least 7 days before the investigation. All measurements were performed when amino acids had been infused for at least 4 hours and thus expected to support the resynthesis of lean body mass. Patients treated in the ICU and the surgical ward were in positive whole‐body energy balance (+1127 ± 121 and +917 ± 123 kcal, respectively). Glucose uptake and oxygen consumption across the leg were similar in both patient groups. Glycerol release was not different from zero balance, indicating that inhibition of lipolysis across the leg during feeding and lactate was normally released in both groups. However, approximately 50% of the patients treated in the ordinary ward and 80% to 100% of the patients in the ICU remained in negative amino acid balance across the leg as judged from significant release of either methionine, tyrosine, or phenylalanine despite concomitant infusion of amino acids (~0.3 g of N per kilogram per day) and nonprotein calories. The results confirm previous results demonstrating that conventional TPN as used in many hospitals does not support efficiently the resynthesis of lean body mass in a considerable number of surgical patients. The reason for this is unknown, but it may be due to both the underlying disease and to less than optimal nutrition. (Journal of Parenteral Enteral Nutrition 15:669–675, 1991)
Comparison of Tolerance and Nutritional Outcome Between a Peptide and a Standard Enteral Formula in Critically Ill, Hypoalbuminemic Patients
Authors: Mowatt‐Larssen Christine A. , Brown Rex O. , Wojtysiak Stacey L. , Kudsk Kenneth A.
Published: May 2008

Dipeptides have been reported to be more efficiently absorbed from the gastrointestinal tract than free amino acids. The objective of this study was to compare prospectively a peptide enteral formula (PEF) with a standard enteral formula (SEF) for tolerance and nutritional outcome in acutely injured, hypoalbuminemic (<3.0 g/dL) patients who require enteral nutrition support. The prevalence of diarrhea and elevated gastric residuals was assessed daily. Prealbumin, transferrin, colloid oncotic pressure, Prognostic Nutritional Index, and nitrogen balance were measured on days 0, 5, and 10 of enteral nutrition support.

Forty‐one patients received 345 days of enteral nutrition support. Prevalences of diarrhea and elevated gastric residuals were similar between groups. Prealbumin increased and the Prognostic Nutritional Index decreased significantly from baseline at day 10 in both groups. Transferrin increased in both groups, but not significantly. Colloid oncotic pressure increased significantly from baseline at days 5 and 10 in the SEF group and day 10 in the PEF group. Nitrogen balance increased significantly from baseline at days 5 and 10 in each group. The only significant difference between groups was for nitrogen balance at day 10, which was higher in the SEF group. We conclude based upon our selected measurements of tolerance and nutritional outcome PEF seams to offer no advantage over SEF in acutely injured, hypoalbuminemic patients. (Journal of Parenteral and Enteral Nutrition 16:20–24, 1992)
Protein Malnutrition Alone and in Combination with Endotoxin Impairs Systemic and Gut‐Associated Immunity
Authors: Deitch Edwin A. , Dazhong Xu  , Lu Qi  , Specian Robert D. , Berg Rodney D.
Published: May 2008

Because protein‐malnourished or endotoxemic patients are at an increased risk of developing nosocomial infections, this study was performed to investigate the effects of protein malnutrition and endotoxemia, alone and in combination, on systemic and intestinal immunity. Protein malnutrition was created by feeding the animals a solid diet containing 0.03% protein. Subgroups of these protein‐malnourished mice were killed after being challenged with saline or endotoxin on days 0, 7, 14, or 21. At death, the animals were weighed, tissues were harvested for histologic analysis (ileum, mesenteric lymph node [MLN], liver, and spleen), mitogen responsiveness (MLN, Peyer's patches, and spleen), and xanthine oxidase measurements (ileum and cecum). Separate groups were evaluated for survival. Both the saline and endotoxin‐challenged mice had lost about 30% of their body weight after 21 days on the low‐protein diet. The protein‐malnourished mice were more susceptible to endotoxin‐induced mortality (70% at 21 days) than the normally nourished mice (0%) (p<.001). The mitogen responsiveness of the protein‐malnourished mice to the T‐cell mitogens (PHA and Con‐A) progressively decreased the longer the mice were protein malnourished, and this decrease in blastogenic responsiveness was associated with histologic evidence of lymphoid atrophy. In contrast, the blastogenic response to the primarily B‐cell mitogen, PWM, was largely preserved. The endotoxin challenge further depressed the immune state of mice tested after 0, 7, or 14 (but not 21) days of protein malnutrition. Thus, both protein malnutrition and endotoxin impaired systemic and gut‐associated immune responsiveness to mitogens. However, in the protein‐malnourished. mice, the degree of immune suppression did not correlate with endotoxin‐induced mortality. (Journal of Parenteral and Enteral Nutrition 16:25–31, 1992)
Effect of Rate of Enteral Nutrient Supply on Gut Mass
Authors: Zaloga Gary P. , Ward Black Kimberly , Prielipp Richard
Published: May 2008

Early enteral feeding after injury is important for maintenance of gut integrity. However, enteral nutrients are frequently administered at low rates because of decreased gastrointestinal motility. These low rates are said to “maintain the gut.” This study was performed to evaluate the effect of rate of enteral nutrient delivery on gut mass.

Six male Sprague‐Dawley rats had no surgery and served as controls (ad libitum rat chow diet). Twenty‐four male Sprague‐Dawley rats underwent abdominal surgery for placement of gastroduodenal feeding tubes (tip located 2 cm into intestine from pylorus) and were randomized (n = 6 per group) to ad libitum rat chow, 1/2 strength peptide diet (Reabilan HN, RHN) at 1 mL/h (1/2RHN‐1 mL), full‐strength peptide diet at 2 mL/h (RHN‐2 mL), or full‐strength peptide diet at 4 mL/ h (RHN‐4 mL). These diets supplied approximately 30%, 13%, 50%, and 100% of rat recommended daily allowances.

The control animals gained weight (38 ± 3 g over 5 days) whereas all postsurgery animals lost weight. Weight loss was greatest in the 1/2 RHN‐1 mL (‐55 ± 3 g over 5 days) and RHN‐2 mL (‐52 ± 6 g over 5 days) groups compared with the RHN‐4 mL animals (‐41 ± 5 g over 5 days). All animals fed liquid enteral diets had reduced gut weights compared with chow‐fed animals. Gut weights did not differ between control and postsurgery ad libitum chow animals. Proximal gut mucosal protein content was significantly (p <.05) higher in the RHN‐4 mL animals (0.88 ± 0.03 mg/cm) compared with control (0.74 ± 0.003 mg/cm) and ad libitum chow animals (0.73 ± 0.05 mg/ cm). There were no differences in mid‐ and distal gut mucosal protein levels between groups. We conclude that the rate of enteral feeding has little effect on gut mass in the early (5 day) postoperative period in rats. (Journal of Parenteral and Enteral Nutrition 16:39–42, 1992)