摘要:

All infections, no matter how mild, decrease nutrient intakes and increase nutrient losses even when sub‐clinical. The losses include decreased intestinal absorption, direct loss of nutrients in the gut, internal diversion for metabolic responses to infection and increased basal metabolic rate when fever is present. In this way, infection influences not only protein and energy status but also that of most other nutrients. The clinical importance of these consequences of infection depends on the prior state of the individual, the nature and duration of the infection, and the diet of the individual during the infection, particularly dietary intake during the convalescent period and whether full recovery takes place before another infection occurs. In industrialized countries particular attention must be paid to the nutrition of hospitalized patients inasmuch as they are frequently debilitated by their primary disease, morbidity, and nutritional status. Morbidity and mortality are increased by nosocomial infections to which the poorly nourished individual is more susceptible. (Journal of Parenteral and Enteral Nutrition15:589–600, 1991)

ISSN:0148-6071    

DOI:10.1177/0148607191015006589

出版商:SAGE Publications    

年代:1991

数据来源: WILEY

摘要:

Fatty infiltration of the liver with cholestasis is one of the complications of total parenteral nutrition (TPN). The cause has not yet been determined. It seems probable, however, that these alterations could be prevented when a mixture of medium‐ and long‐chain triglycerides (MCT/LCT) is used as a fat component instead of the application of long‐chain emulsions (LCT) alone. To determine whether this could also be demonstrated morphologically in man, 14 patients needing TPN (25 kcal/kg BW x day, carbohydrate 45%, fat 35%, protein 20%) were examined by ultrasound in order to compare liver size and gray‐scale value before and after 7 days of TPN. Seven of the patients were randomly administered a MCT/LCT emulsion as their fat intake, the other seven were exclusively given LCT. There were no changes in liver size and gray‐scale value in the MCT/LCT‐group, whereas both parameters showed a significant rise in the patients with LCT (size: 10.4 ± 1.4 to 11.5 ± 1.4 cm; gray‐scale value: 9.3 ± 1.0 to 11.6 ± 0.7). These data suggest that TPN, administered with a mixture of MCT/LCT emulsions as fat components, could reduce the risk of hepatic dysfunction such as cholestasis and fatty infiltration of the liver. (Journal of Parenteral and Enteral Nutrition15:601–603, 1991)

ISSN:0148-6071    

DOI:10.1177/0148607191015006601

出版商:SAGE Publications    

年代:1991

数据来源: WILEY

摘要:

The aim of this study was to assess the impact of surgical trauma on energy metabolism in cancer patients. Therefore, resting energy expenditure (REE) was determined before and after surgery in patients with newly detected gastric and colorectal cancer. Preoperative REE was measured in 104 patients. In 65 of these 104 patients REE was also measured on the seventh or eighth postoperative day. Postoperative REE was significantly higher than preoperative REE (mean ± SD: 1471 ± 238us1376 ± 231 kcal;p<0.001). After surgery 22 patients were hypermetabolic (REE ≥ 115% predicted energy expenditure) compared with seven hypermetabolic patients before surgery. This hypermetabolism in the postoperative state can be explained by the administration of total parenteral nutrition (TPN), by an increased body temperature mainly as a consequence of postoperative complications and by the surgical trauma itself. Patients who received preoperative TPN (n = 12) showed a 10% increase in REE. Thirteen patients suffered from minor and major postoperative complications; postoperative REE in this group was increased by 10%. Forty patients who had undergone uncomplicated surgery showed a slight but significant increase of 3% in REE after operation. We conclude from this study that the increase in REE resulting from surgical trauma itself is modest at the seventh to eighth postoperative day. Therefore, energy requirements for patients undergoing major elective surgical stress are lower than generally presumed. (Journal of Parenteral and Enteral Nutrition15:604–607, 1991)

ISSN:0148-6071    

DOI:10.1177/0148607191015006604

出版商:SAGE Publications    

年代:1991

数据来源: WILEY

摘要:

Precipitation of calcium phosphate in neonatal total parenteral nutrition (TPN) solutions remains a significant problem. Whereas numerous studies have attempted to establish guidelines for maximum concentrations of various combinations that can be mixed, differences in study design and reliance upon subjective visual assessment severely limit their applicability. The purpose of this study was to quantitatively determine calcium and phosphate compatibility in commonly used neonatal TPN solutions containing a final concentration of either 1 or 2% amino acids. The final dextrose concentration was 10%. Electrolytes, heparin, and pediatric vitamins and trace minerals were also added. Calcium gluconate (10%) and potassium phosphate (mono and dibasic) were added by calibrated micropipetors. Calcium concentrations ranged from 5 to 60 mEq/L and phosphate from 5 to 40 mM/L with a minimum of 84 combinations tested for each amino acid concentration. Calcium concentrations were measured in duplicate for each tested combination. Control solutions containing calcium but no phosphate were included to validate the assay methodology. All samples were stored at room temperature for 23.5 hours and then placed in a water bath at 37°C for 30 minutes to simulate incubator conditions encountered during TPN infusion. Calcium determinations were then repeated and precipitation was judged to have occurred whenever calcium concentrations fell below 90% of the initial measured values. These data allowed plotting a calcium and phosphorus reference curve for TPN solutions containing 1 and 2% amino acids based on quantitative assessment. These reference curves should allow pharmacists to avoid compounding TPN solutions that will precipitate, thus saving considerable cost to the pharmacy and preventing complications. (Journal of Parenteral and Enteral Nutrition15:608–611, 1991)

ISSN:0148-6071    

DOI:10.1177/0148607191015006608

出版商:SAGE Publications    

年代:1991

数据来源: WILEY

摘要:

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 Nutrition15:612–618, 1991)

ISSN:0148-6071    

DOI:10.1177/0148607191015006612

出版商:SAGE Publications    

年代:1991

数据来源: WILEY

摘要:

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 Nutrition15:619–624, 1991)

ISSN:0148-6071    

DOI:10.1177/0148607191015006619

出版商:SAGE Publications    

年代:1991

数据来源: WILEY

摘要:

Measurement of O2uptake (VO2) and C02output (VCO2) with automated instruments can be used to optimize nutritional management of critically ill patients. However, these measurements may be made infrequently because of calibration problems or suspected inaccuracies, especially when the patient is given supplemental oxygen. A simple method is described for periodic testing of automated gas exchange measurements. While a test lung is mechanically ventilated an accurately known mixture of C02and nitrogen is introduced into the inspired gas, simulating VO2by dilution and VCO2by addition of CO2. The ratio of VCO2:VO2(respiratory gas exchange ratio, R) in the “expired gas” should be [FGco2/(1‐ FGcO2)] x [(1 ‐ FIO2)/FIO2], where FGCO2is the fraction of CO2in the diluting gas and FIO2is the fraction of O2in the inspired gas. R is independent of the flow rate of the diluting gas or the rate of ventilation of the test lung. Using a mixing chamber‐mass spectrometer, we found that R calculated from measurement of CO2and O2concentrations in the simulated mixed expired gas closely matched the predicted R for FIO2= 0.21 — 0.50. On the other hand, when an automated gas exchange measurement device was tested, R was sometimes excessively high, especially for FIO2>0.35. This method, using a single diluting gas and without precision flowmeters, may be useful for periodic testing of respiratory gas exchange instruments in the intensive care unit. If a discrepancy is found between measured and predicted R, measurements should not be relied upon until further calibration or repairs can be effected. (Journal of Parenteral and Enteral Nutrition15 :625–629, 1991)

ISSN:0148-6071    

DOI:10.1177/0148607191015006625

出版商:SAGE Publications    

年代:1991

数据来源: WILEY

摘要:

Wistar rats were divided into two groups, intraperitoneal sepsis group (group IS) and total parenteral nutrition group (group TPN), to evaluate the characteristics of pathologic alterations in rats with cholestasis. Biochemical assay showed that cholestasis developed in both groups after 10 days. Light microscopic examination of liver specimens revealed that the degeneration in the intermediate and external zone of hepatolobules was the major alteration in group IS, and group TPN showed characteristic dilation of central veins and hepatic sinuses and the proliferation of Kupffer cells with marked phagocytosis. Electron microscopic pictures presented the enlargement of bile canaliculi with altered microvilli in group IS and many highly electron‐dense bile particles within cytoplasm and secondary lysosomes near dilated bile canaliculi in group TPN. It is concluded that there were different histopathologic alterations of liver specimens in TPN‐supported animals and septic animals when cholestasis developed. It is unsuitable to take intraperitoneal sepsis as a unique factor of cholestasis in TPN‐supported rats. Bile stasis is only one sign of TPN‐induced hepatic lesion, which needs further exploration to determine its causes and mechanisms. (Journal of Parenteral and Enteral Nutrition15:630–636, 1991)

ISSN:0148-6071    

DOI:10.1177/0148607191015006630

出版商:SAGE Publications    

年代:1991

数据来源: WILEY

摘要:

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 Nutrition15:637–641, 1991)

ISSN:0148-6071    

DOI:10.1177/0148607191015006637

出版商:SAGE Publications    

年代:1991

数据来源: WILEY

摘要:

The possible beneficial effects of infusing a lipid emulsion containing 50% by weight of medium‐chain triglycerides (MCT) compared with a standard long‐chain triglyceride (LCT) emulsion were studied in 18 premature neonates (gestational age<34 weeks) requiring parenteral nutrition. The infants were assigned in a double‐blind manner to receive one of the two lipid emulsions over 17 hours a day as a supplemental regimen for total parenteral nutrition. A lipid load of 1 g/kg per day was initiated on the third day of life and was increased at the rate of 1 g/kg per day until a maximal dose of 3 g/kg per day was obtained on the fifth day of life and maintained thereafter. Both bound and unbound bilirubin decreased with both infusion regimens during the study period. Despite a marked increase in plasma free fatty acid levels (260% in the MCT/LCT group compared with 210% in the LCT group), the fraction of unbound (free) bilirubin was significantly lower in the MCT/LCT group (34% vs 13%). Free fatty acid levels, corrected to albumin, were positively correlated to the percentage of free bilirubin only for the LCT lipid infusion. The finding of a significant elevation of plasma cholesterol levels only in the MCT/LCT group is now under investigation. Use of the MCT‐containing emulsion was not associated with a higher frequency of adverse effects than the commonly used LCTcontaining emulsion. It is concluded that the lipid emulsion containing MCT is safe for use as a calorie source in lipid supplementation of total parenteral nutrition in premature infants under the conditions studied and that it is probably preferable in situations in which hyperbilirubinemia limits the use of the conventional LCT emulsion. (Journal of Parenteral and Enteral Nutrition15:642–646, 1991)

ISSN:0148-6071    

DOI:10.1177/0148607191015006642

出版商:SAGE Publications    

年代:1991

数据来源: WILEY