摘要:

Total parenteral nutrition is required by all patients in need of small bowel transplantation. Untoward side effects of total parenteral nutrition include atrophy and hypofunction of the small intestine. Glutamine, the preferred fuel for the enterocyte, is presumably present in insufficient amounts in diets given to patients with intestinal dysfunction. In a rat model of total parenteral nutrition and small bowel transplantation, this study investigated the following: (1) whether glutamine improves graft structure and function, (2) the optimal route of glutamine delivery (intravenousvsdirect infusion into the graft), and (3) the effect of glutamine on ultrastructure of the graft enterocyte. Lewis rats underwent small bowel transplantation as a Thiry‐Vella graft and received total parenteral nutrition for 14 days while assigned to one of four infusion groups: 2% intravenous glutamine; 2% intravenous isonitrogenous mixture, nonessential amino acids (control); 2% glutamine into the graft; or 2% nonessential amino acids into the graft (control). Graft mucosal villous height, villous surface area, crypt depth, weight, protein, deoxyribonucleic acid content, glucose absorption, and enterocyte ultrastructure were then evaluated. Infusion of glutamine directly into the graft significantly increased mucosal villous height (p=.045), surface area (p=.029), and glucose absorption (p=.004) when compared with controls. Intravenous glutamine infusion significantly increased mucosal villous height (p=.002), surface area (p=.001), weight (p=.005), and glucose absorption (p=.04) when compared with controls. Most enterotrophic and functional benefits of glutamine were not significantly different between intravenous infusions and direct administration into the graft. Intravenous glutamine maintained normal enterocyte ultrastructure of the graft when compared with intravenous combined nonessential amino acids. These results indicate that glutamine supplementation improves structure and function in a rat model of total parenteral nutrition and small bowel transplantation. (Journal of Parenteral and Enteral Nutrition 17:47–55, 1993)

ISSN:0148-6071    

DOI:10.1177/014860719301700147

出版商:SAGE Publications    

年代:1993

数据来源: WILEY

摘要:

Our purpose was to extend previous studies of the stability of vitamins A (retinol palmitate), E (tocopherol acetate), and K1(phylloquinone) to total parenteral nutrition at‐home (TPNH) admixtures. First, stability over 20 days was tested. Experimental conditions included presence or absence of lipids, presence or absence of trace elements, and storage in a glass bottle or in a single or multi‐layer plastic bag (ethylene vinyl acetate, polyvinyl chloride, Stedim 5, and Stedim 6). The 20‐day storage studies were conducted at 4°C or at ambient air temperature. The second part of the study consisted of exposing to natural light TPNH admixtures with or without lipids, but with trace elements, in the same containers (except polyvinyl chloride). Finally, a clinical situation of TPNH was simulated with a TPNH admixture prepared 11 days before the test in a Stedim 6 plastic bag and stored at 4°C in total darkness. For vitamins A, E, and K1, we observed good stability for 20 days; the final concentrations ranged from 75% to 100% of initial concentrations whatever the conditions studied. It appears that there is no significant difference of action between all containers and that the presence or absence of lipids and trace elements in admixtures stored at 4°C or ambient temperature makes no difference. With exposure to sunlight, vitamin losses were 100% at 3 hours for vitamin A and 50% for vitamin K1; vitamin E concentrations were unchanged after 12 hours of experiment. The presence of lipids or type of container did not appear to enhance protection from direct sunlight. Finally, we showed that, under standardized conditions of preparation, storage, and administration of TPNH such as those used in the pharmaceutical department of Debrousse Hospital, the amounts of vitamins A, E, and K1that were administered to patients adequately corresponded to the amounts of vitamins prescribed and added to TPN admixtures. (Journal of Parenteral and Enteral Nutrition 17:56–60, 1993)

ISSN:0148-6071    

DOI:10.1177/014860719301700156

出版商:SAGE Publications    

年代:1993

数据来源: WILEY

摘要:

A prospective study was undertaken to compare the silver‐impregnated collagen cuff (Vitacuff) with the bedside tunneled catheter. Fifty patients were randomly assigned to three groups: group I received triple‐lumen catheters with Vitacuff application and a semiocclusive dressing material; group II received triple‐lumen tunneled catheters with a semiocclusive dressing; and group III received triple‐lumen tunneled catheters with collodion as a dressing material. In patients suspected of having central venous catheter sepsis, blood cultures were obtained through the catheter, the catheter was removed, and the tip was cultured semiquantitatively. Central venous catheter sepsis was defined as a positive catheter‐tip culture and blood culture for the same organism. No catheter‐related sepsis was seen in either the Vitacuff or the tunneled catheters with collodion dressing. In the tunneled catheters with semiocclusive dressing, there was one case of catheter‐related sepsis and one case of insertion‐site infection. There was also one insertion‐site infection in the Vitacuff group, but there was no statistical difference in infection rates between the three groups. (Journal of Parenteral and Enteral Nutrition 17:61–63, 1993)

ISSN:0148-6071    

DOI:10.1177/014860719301700161

出版商:SAGE Publications    

年代:1993

数据来源: WILEY

摘要:

Plasma glucose was studied during the initiation of total parenteral nutrition (TPN) and the discontinuation of TPN without a tapering schedule. Blood was sampled every 5 minutes for 2 hours after the start of TPN and 1 week later as TPN was discontinued. A total of 14 initiations and 14 discontinuations were studied in 18 patients. Severity of illness in patients ranged from stable condition postoperatively to multiple‐system failure; six patients had diabetes mellitus. The TPN solution was a 3:1 admixture that provided a caloric intake equal to 1.2 times the resting energy expenditure, with 40% fat and 60% carbohydrate calories. An average of 1963 kcal was provided per day (340 g of glucose, 79 g of fat). During the initiation phase, the mean increase in plasma glucose was 60 mg/dL. The increase for diabetic patients was 79 ± 14 mg/dL compared with 52 ± 23 mg/dL for the nondiabetics. During the discontinuation phase, the mean plasma glucose decreased 40 ± 20 mg/dL; two patients with high concentrations of regular insulin (50 and 100 units) showed an increase in plasma glucose when the TPN was stopped. Plasma glucose returned to the preinfusion baseline after discontinuation. During both initiation and discontinuation, plasma glucose showed little change after the first 60 minutes. No clinical symptoms of hypoglycemia were observed. In conclusion, TPN as a 3:1 admixture can be safely started as full nutrition support and stopped abruptly without a tapering schedule. Plasma glucose response is rapid, predictable, and mostly complete within 60 minutes. (Journal of Parenteral and Enteral Nutrition 17:64–67, 1993)

ISSN:0148-6071    

DOI:10.1177/014860719301700164

出版商:SAGE Publications    

年代:1993

数据来源: WILEY

摘要:

Minimal information is available defining urinary nitrogen constituents in preterm neonates receiving parenteral nutrition (PN). The study objective was to evaluate 24‐hour urine collections for total urinary nitrogen (TUN), urinary urea nitrogen (UUN), and the nitrogen content in creatinine, ammonia, free amino acids, protein, hippuric acid, and uric acid at baseline (days 1 to 2 of PN and days 1 to 3 after surgery) and 7 days later in eight preterm, postsurgical neonates. Calculation of undetermined nitrogen was also completed. Comparisons with historic, normal data were made for each urinary nitrogen constituent. At baseline, PN provided 59 ± 10 nonprotein kcal/kg·day−1and 430 ± 54 mg/kg·day−1. At day 7, PN provided 106 ± 23 nonprotein kcal/kg. day−1and 432 ± 30 mg/ kg·day−1. TUN, UUN, and protein nitrogen decreased significantly from baseline at day 7 (p<.05). The percentages of TUN as amino acids, creatinine, and uric acid nitrogen were calculated. Percent amino acid nitrogen (6.0 ± 2.3%vs8.4 ± 1.5%, p<.05), percent creatinine nitrogen (1.6 ± 0.5%vs2.9 ± 0.8%, p<.001) and percent uric acid nitrogen (1.7 ± 0.9%vs3.6 ± 2.1%, p<.05) increased significantly at day 7. The observed urinary free amino acid nitrogen fraction represented a higher percentage of TUN both at baseline and at day 7 when compared with term neonatal reference data, whereas creatinine nitrogen, uric acid nitrogen, and protein nitrogen represented a lower percentage of TUN. However, amino acid and creatinine nitrogen as a percentage of TUN were similar to levels in milk formula‐fed preterm infants. The advancement of nonprotein calories and the likely decrease in physiologic stress at day 7 contributed to decreased TUN, UUN, and protein nitrogen excretion. Undetermined nitrogen remains a significant fraction of nitrogen losses in preterm neonates receiving PN. (Journal of Parenteral and Enteral Nutrition17:68–72, 1993)

ISSN:0148-6071    

DOI:10.1177/014860719301700168

出版商:SAGE Publications    

年代:1993

数据来源: WILEY

摘要:

The influence of surgical stress on the function of the reticuloendothelial system (RES) is not well elucidated. Because we established an in vivo functional test for the RES by using chondroitin sulfate iron colloid in rabbits, the normal range of RES function in healthy volunteers (n = 12) and the dynamic change of RES function in surgical patients after distal gastrectomy (n = 14) were examined by this method. In healthy volunteers, the maximum phagocytic velocity and membrane‐particle constant were 0.0310 ± 0.0052 mg/kg per minute and 0.575 ± 0.205 mg/kg, respectively. In surgical patients, maximum phagocytic velocity (postoperative day 1, 0.0408 ± 0.0088; postoperative day 3, 0.0486 ± 0.0115; and postoperative day 7, 0.0430 ± 0.0115 mg/kg per minute) and membrane‐particle constant (postoperative day 3, 0.717 ± 0.169 mg/kg) significantly increased postoperatively in comparison with preoperative values. These results indicate that the total capacity of the RES is augmented but that its functional phagocytic efficiency is diminished after abdominal surgery. This phenomenon is considered to be one of the immunological alterations caused by surgical stress. The chondroitin sulfate iron colloid test can be applied to monitor the dynamic change of the RES function under various conditions. (Journal of Parenteral and Enteral Nutrition 17:73–76, 1993)

ISSN:0148-6071    

DOI:10.1177/014860719301700173

出版商:SAGE Publications    

年代:1993

数据来源: WILEY

摘要:

This preliminary study was undertaken to ascertain whether our newly developed model of the cold ischemic rat liver in situ is applicable to studies designed to assess the metabolism of nutrients. Ischemia of the whole liver of 12 Wistar rats was induced by clamping all supply and drainage vessels. The ischemic liver was perfused insitu.The duration of ischemia of the liver was 20 minutes. Saline was infused into six rats throughout the experiment (group A). An intravenous infusion of glucose at a rate of 0.75 g/h per rat was begun immediately after the induction of blood‐reflow to the liver (group B, n = 6). Six rats (group C) did not undergo the procedure for induction of hepatic ischemia and received glucose at the same rate as rats in group B. Changes in hepatic levels of sugar phosphates (phosphomonoesters [PMEs]), inorganic phosphorus, and β‐positioned phosphorus in adenosine triphosphate (β‐ATP) were monitored by31P magnetic resonance spectroscopy. Ischemia caused a significant increase in levels of PMEs and a decrease in levels of β‐ATP. The infusion of glucose caused a further increase in levels of PMEs and a further decrease in levels of β‐ATP in group B. In contrast, in group C such infusion did not induce any changes in levels of PMEs or β‐ATP. In group A, PMEs and β‐ATP returned to basal levels 5 hours after the induction of blood‐reflow to the liver. The changes in levels of PMEs were similar to those in levels of inorganic phosphorus in all groups. All rats in groups A and C regained consciousness and survived, whereas all rats in group B died 4 or 5 hours after the induction of blood‐reflow to the liver. Thus, it was demonstrated that the early supply of large amounts of glucose induces the accumulation of sugar phosphates and inhibits restoration of hepatic levels of ATP. The results suggest that our newly developed model of cold ischemia of the rat liver in situ can be applied to studies designed to elucidate appropriate nutrients for the liver recovering from cold ischemia. (Journal of Parenteral and Enteral Nutrition 17:77–81, 1993)

ISSN:0148-6071    

DOI:10.1177/014860719301700177

出版商:SAGE Publications    

年代:1993

数据来源: WILEY

摘要:

Long‐term total parenteral nutrition results in atrophy of small intestinal structure and function. Maintenance or re‐establishment of enteral nutrition can prevent or redress this loss. Paradoxically, the fetus develops in a total parenteral nutrition environment, but at the same time must achieve appropriate levels of gastrointestinal maturation in readiness for enteral feeding soon after birth. The fetus swallows large amounts of fluid during life in utero and growth is arrested if fetal ingestion is impaired. It is possible therefore that enteral nutrition provided by fetal swallowing is just as important in ensuring normal gastrointestinal homeostasis and growth in the fetus as it is in the adult. (Journal of Parenteral and Enteral Nutrition 17:82–85, 1993)

ISSN:0148-6071    

DOI:10.1177/014860719301700182

出版商:SAGE Publications    

年代:1993

数据来源: WILEY

摘要:

This is a case report on six patients with hyperammonemia that developed while they were receiving total parenteral nutrition (TPN) as a component of renal failure therapy. Clinically, the hyperammonemia presented as mental status changes in all six cases. Four of the six patients with renal failure initially received 400 mL Amiyu in 1400 mL 17% glucose (total = 1800 mL TPN‐A) administered over each 24‐hour period. Two patients had been placed on 400 mL complete amino acid in 1400 mL 17% glucose (total = 1800 mL TPN‐C over each 24‐hour period) prior to therapy with TPN‐A. Approximately 3 weeks after initiation of TPN therapy with TPN‐A, episodes of mental status changes of increasing duration and paroxysms were documented in five of the six patients. In one of the patients receiving TPN‐C prior to TPN‐A therapy, toxicity was clinically evident only 4 days after initiation of TPN‐A. Serum ammonia levels were obtained and found to be elevated in the acute (ie, presenting) stage in all patients. With the discontinuance of TPN‐A, ammonia levels normalized uniformly. Mental status also improved in all cases except for the patient with rapid clinical presentation who died 2 weeks after first evidence of clinical toxicity. In cases 1, 2, and 6, serum amino acid analysis in the acute phase showed reduced levels of ornithine and citrulline, the substrate and product, respectively, of condensation with carbamyl phosphate at its entry into the urea cycle. Moreover, levels of arginine, precursor to ornithine, were found to be elevated. And, in cases 1 and 6, the serum concentration of orotic acid was 40 times and 23 times, respectively, the value expected in a normal healthy adult. This is presumably due to funneling of carbamyl phosphate into an alternate biosynthetic pathway as a result of inadequate ornithine needed as substrate for its entrance into the urea cycle. Thus, the common denominator in the hyperammonemia experienced in these cases appears to be a depletion of ornithine stores, which we hypothesize to have mainly resulted from inhibition of arginosuccinate synthetase by histidine. Consequently, in patients requiring long‐term TPN therapy (>3 weeks in our experience with TPN‐A), it may be necessary to supplement ornithine in addition to arginine. In all such patients, we feel it is necessary to monitor serum ammonia for toxicity or long‐term elevation. (Journal of Parenteral and Enteral Nutrition 17:86–90, 1993)

ISSN:0148-6071    

DOI:10.1177/014860719301700186

出版商:SAGE Publications    

年代:1993

数据来源: WILEY

摘要:

We report a case of inadvertent azygos placement of a central venous catheter. The patient experienced ill‐defined back pain associated with total parenteral nutrition infusion. The catheter malposition remained unrecognized and resulted in extensive diagnostic work‐up. Symptoms resolved after the catheter was withdrawn. (Journal of Parenteral and Enteral Nutrition 17:91–93, 1993)

ISSN:0148-6071    

DOI:10.1177/014860719301700191

出版商:SAGE Publications    

年代:1993

数据来源: WILEY