Selenium status of seven chronic intravenous hyperalimentation patients

Selenium status was determined on seven patients receiving long-term intravenous hyperalimentation (IVH) and they were followed monthly for 4 to 17 months. Analysis of the IVH solutions for selenium revealed no detectable amounts. The selenium indices measures were (1) erythrocyte selenium levels, (2) erythrocyte glutathione peroxidase activities (GSH-Px), and (3) plasma selenium levels. In general, the IVH population had significantly lower values (p less than 0.001) for these selenium indices than a healthy population (n = 275). The plasma selenium levels decreased to below the normal range within one to two months after initiation of IVH. The below normal ranges varied by patient: three patients by three months, one patient by nine months, and three patients had low and normal values throughout the study. No consistent correlation of individual patient's erythrocyte GSH-Px activities and erythrocyte selenium levels existed, but a positive correlation (r = 0.51, p less than 0.01) occurred between plasma selenium levels and erythrocyte GSH-Px activities. Thus, erythrocyte GSH-Px activities decrease parallel to decreases in plasma selenium levels but not with changes in erythrocyte selenium levels. These data suggest that some of these IVH patients may be at risk for selenium deficiency and that selenium supplementation of IVH solutions may be required. Furthermore, these data suggest that the measurement of erythrocyte GSH-Px activity or selenium levels in some IVH patients may not be related to available body selenium.     

Thiamin and pyridoxine requirements during intravenous hyperalimentation.

Studies were undertaken to determine rational dosages of vitamin B1 and B6 during long-term intravenous hyperalimentation, using more sensitive techniques than formerly used to evaluate B1 and B6 status. A standard vitamin combination, type A, (usually commercially available products) has been used up to now because of convenience, disregarding the effects of long-term administration. This combination lacks biotin, folic acid, and vitamin E and contains from 10 to 100 times the dietary allowances of such vitamins as B1, B2, B6, B12, and C. In response to the possibility of vitamin overdose, two new vitamin combinations, type B (from commercial products) and type C (a convenient and easily administered combination produced at the hospital) were developed in order to provide the normal dietary allowances and at the same time eliminate any harmful side-effects. From the results obtained, 5 mg/day for thiamin HCl and 3 mg/day for pyridoxine HCl in type B and type C were found to be a sufficient and safe level as opposed to 55 mg/day for thiamin HCl and 102 mg/day for pyridoxine HCl in type A.     

Guillain-Barré syndrome due to hypophosphatemia following intravenous hyperalimentation

This case report documents the additive effects of pregnancy, hyperemesis, cholecystitis, and intravenous nutrition in causing profound hypophosphatemia. This led to severe reversible neurological sequelae for the mother and fetal demise. The etiology of hypophosphatemia and management are discussed.     

Plasma proteins in patients receiving intravenous amino acids or intravenous hyperalimentation after major surgery.

Eleven plasma proteins were compared for each of three groups of 10 closely matched patients before and 15 days after rectal excision who were receiving an addition to oral diets the following parenteral solutions by central venous catheter: 1) no hyperalimentation, 2) hypertonic glucose plus amino acids, or 3) amino acids alone. Plasma transferrin, prealbumin, and retinol-binding protein were normal before surgery in all but seven patients. Postoperatively, concentrations were decreased, but were restored to normal after full hyperalimentation whereas they were significantly less and lower than normal in controls and patients receiving amino acids. Acute phase proteins were higher than normal before surgery and also 15 days later. Lower values in patients receiving hyperalimentation were mainly due to hydration compared with higher values in the other groups caused by the higher incidence of sepsis. It is concluded that full hyperalimentation after major surgery restores "visceral" proteins more rapidly than by infusion of amino acids alone and is associated with fewer clinical complications.     

Influence of intravenous hyperalimentation on cardiac dimensions and heart function

Eleven severe malnourished patients, mean age 34 yrs and mean weight 66 per cent of ideal body weight, were studied to evaluate the effect of intravenous hyperalimentation on the function and size of the heart. Left ventricular size and systolic function were measured before and after a mean weight gain of 19 per cent with electro, vector, echo and phonomechanographic methods. During hyperalimentation a statistically significant increase in left ventricular mass (p<0.01) was observed. Correction for body weight showed a parallel increase between the parameters and weight gain. Echocardiographic and phonomechanographic indexes of left ventricular systolic function remained unchanged. A decrease of the amplitude of the maximal spatial QRS vector was shown by vectocardiography. These results indicate that during intravenous hyperalimentation of the severe malnourished a proportional increase in cardiac size and mass occurs with preservation of the left ventricular systolic function.     

Pancreatic secretory responses to intravenous hyperalimentation and intraduodenal elemental and full liquid diets

Intravenous hyperalimentation and enteral elemental diets have both been advocated for the nutritional support of patients with acute pancreatitis, pancreatic fistula, and proximal small bowel fistula. The exocrine pancreatic responses to these nutrients compared to one another and to full liquid diet have been inadequately studied. Therefore, pancreatic protein, volume, and bicarbonate responses to graded doses of (1) intravenous hyperalimentation, (2) intraduodenal elemental diet, and (3) intraduodenal full liquid diet were compared in duplicate experiments in five dogs with chronic pancreatic fistulas. Both intraduodenal elemental and full liquid diets caused comparable and significant dose-related increases in pancreatic protein, volume, and bicarbonate outputs over basal levels (p less than 0.05). In contrast, there was no stimulation of pancreatic secretion by intravenous hyperalimentation. It therefore appears that of the methods studied, only intravenous hyperalimentation can provide full nutritional support while maintaining the pancreas at rest.     

Plasma concentrations of transsulfuration pathway products during nasoenteral and intravenous hyperalimentation of malnourished patients

We have monitored the plasma concentrations of products of the transsulfuration pathway in 11 undernourished noncirrhotic patients, and in 10 cachectic cirrhotic subjects, before and during nasoenteral nutrition with Vivonex (Norwich-Eaton Pharmaceuticals, Norwich, NY) or total parenteral nutrition (TPN) with FreAmine III (American McGaw, Irvine, CA). In the cirrhotic cases eating a mixed diet, levels of taurine, cysteine, plasma glutathione, and free choline were subnormal. During nasoenteral hyperalimentation, methionine was elevated while cysteine, glutathione, and free choline levels remained depressed. During TPN, levels of taurine, cysteine, protein-bound cysteine, glutathione, free choline, and phosphatidyl choline were depressed and methionine was elevated. In the noncirrhotic cases eating a mixed diet, only the free choline concentration was low. During nasoenteral hyperalimentation, the plasma levels of both free choline and total carnitine were depressed. During TPN, plasma levels of cystine, protein-bound cysteine, total carnitine, free choline, and phosphatidyl choline were subnormal. These data suggest that biosynthesis of several products of the transsulfuration pathway may be inadequate in both cirrhotic and noncirrhotic patients during TPN with FreAmine III.     

医疗设备最优维修策略探讨

目的:分析我国医疗设备在维修管理方面所面临的现状与不足,探讨出几种最优维修策略。方法:把国际上通用的以可靠性为中心的维修(RCM)理论和寿命周期成本(LCC)理论引用到医疗设备的维修管理中,针对目前医疗设备维修管理存在的问题,运用维修理论加以探讨。结果:针对不同类型的医疗设备选择出其最优维修策略。结论:选择最优维修策略,可以降低设备维修成本,减轻患者经济负担,同时也为医院带来更大的经济效益。     

Protein and arginine requirements for maintenance and nitrogen gain in four teleosts

Besides being an indispensable amino acid for protein synthesis, arginine (Arg) is also involved in a number of other physiological functions. Available data on the quantitative requirement for Arg in different teleosts appear to show much variability. So far, there are very limited data on the maintenance requirements of indispensable amino acids (IAA) in fish. In the present study, we compared N and Arg requirements for maintenance and growth of four finfish species: rainbow trout (Oncorhynchus mykiss), turbot (Psetta maxima), gilthead seabream (Sparus aurata) and European seabass (Dicentrarchus labrax). Groups of fish having an initial body weight close to 5-7 g were fed semi-purified diets containing graded levels of N (0 to 8 % DM) and Arg (0 to 3 % DM) over 4 to 6 weeks. For each species, N and Arg requirements for maintenance and for growth were calculated regressing daily N gain against daily N or Arg intakes. N requirement for maintenance was estimated to be 37.8, 127.3, 84.7 and 45.1 mg/kg metabolic body weight per d and 2.3, 2.2, 2.6 and 2.5 g for 1 g N accretion, in rainbow trout, turbot, gilthead seabream and European seabass respectively. The four species studied appear to have very low or no dietary Arg requirements for maintenance. Arg requirement for g N accretion was calculated to be 0.86 g in rainbow trout and between 1.04-1.11 g in the three marine species. Turbot required more N for maintenance than the other three species, possibly explaining its reputedly high overall dietary protein requirement. Data suggest a small but sufficient endogenous Arg synthesis to maintain whole body N balance and differences between freshwater and marine species as regards Arg requirement. It is worth verifying this tendency with other IAA.     

Low arginine plasma levels in patients after thoracoabdominal aortic surgery

OBJECTIVE: Thoracoabdominal aortic surgery is a high-risk procedure and associated with a significant morbidity and mortality. Ischemia reperfusion of visceral organs and lower extremities is one of the most important determinants of this morbidity. Arginine is the precursor of nitric oxide and arginine plasma levels are important in maintaining organ blood flow. Furthermore, arginine is important in wound healing and the immune system. Because of increased utilization of arginine, low arginine plasma levels could be expected after thoracoabdominal aortic surgery. We therefore measured arginine plasma levels in these patients. DESIGN: Six patients with thoracoabdominal aortic aneurysm were included in this study. SETTING: University Hospital Vrije Universiteit, Department of Surgery, Amsterdam, The Netherlands. SUBJECTS: Six patients undergoing thoracoabdominal aortic surgery. INTERVENTION: Plasma levels of arginine were measured by high-performance liquid chromatography. RESULTS: Very low arginine plasma levels were seen on the first postoperative day. From day 1 arginine slowly increased, but did not reach normal plasma levels on day 6. CONCLUSIONS: A significant decrease of arginine plasma levels was found and because of the fact that arginine has multiple functions, it may be important to keep these arginine plasma levels at normal or even higher levels in patients undergoing major vascular surgery. European Journal of Clinical Nutrition (2000) 54, 615-617.     

Effects of an anabolic steroid on plasma amino acids, proteins, and body composition in patients receiving intravenous hyperalimentation

In this controlled trial we have studied the effect of anabolic steroid on ill surgical patients receiving intravenous hyperalimentation. Body composition, plasma proteins, and amino acids were compared in each of two groups of 12 patients before and after 14 days of intravenous feeding. The patients in one group were given 100 mg of nandrolone decanoate at the commencement of study and again one week later. Body weight, muscle (AMC), plasma transferrin, prealbumin, and retinol-binding protein were increased comparably in both groups. An apparent gain in total body nitrogen was not significant. However, anabolic steroid caused greater gain of water requiring a more liberal use of diuretics, but prevented the gains of fat, triglyceride and insulin that occurred in the control group. Most plasma amino acids increased due to intravenous hyperalimentation but decreased in patients given anabolic steroid. It is concluded that in patients who may be in the catabolic phase of recovery anabolic steroid probably enhances amino acid and water uptake by tissues and increases the utilization of fat but, does not promote any greater increase in "visceral" proteins than during intravenous hyperalimentation alone.     

A review of hypersomolar hyperglycemic nonketotic dehydration (HHND): etiology, pathophysiology and prevention during intravenous hyperalimentation.

The records of 200 patients, nutritionally supported by synthetic means, were reviewed for evidence of clinical hyperosmolar hyperglycemic nonketotic dehydration (HHND). There was a 3% incidence of morbidity, with a single mortality. Laboratory values demonstrated a positive correlation between persistent glucosuria and HHND. The pathophysiology of HHND demonstrated a relative insulin lack with sufficient insulin to prevent lipolysis, but insufficient to prevent hyperglycemia, glucosuria and osmotic diuresis. The mechanism and management of the pseudodiabetes of stress is reviewed. It is concluded that HHND is an avoidable iatrogenic morbidity. Prevention of osmotic diuresis secondary to glucosuria and, therefore, prevention of HHND is achieved by providing exogenous insulin sufficient to prevent glucosuria.     

Trace metal abnormalities in adults during hyperalimentation

Trace metal deficiencies are now a well-documented complication of total parenteral nutrition (TPN). Zinc deficiency may present in a variety of ways including acrodermatitis skin lesions, impaired immunity, poor growth or impaired wound healing, and mental disturbances. Copper deficiency presents a more uniform picture of hematologic abnormalities, usually anemia with leukopenia and neutropenia. Chromium and selenium deficiencies occur much less frequently, but well-documented cases have been reported. We currently recommended regular monitoring and supplementation of these four trace metals during TPN administration. This article describes the clinical abnormalities that may develop when deficiencies of trace metals occur during TPN administration, and we present recommendations for trace metal supplementation during TPN administration.     

Prolonged hyperalimentation in catabolic chronic dialysis therapy patients

Plasma concentrations of 25 essential (EAA) and nonessential (NEAA) amino acids were measured pre- and postdialysis in 46 chronic hemodialysis therapy (CDT) patients. Sixteen of these patients with prior weight loss of 14.5 +/- 2.37 pounds in 24 months were administered a GAA solution (EAA + NEAA + glucose) for 20 weeks during each dialysis. Eight of these patients (group 1) responded with improved appetite and weight gain; the remaining eight patients (group 2) with clinically advanced metabolic bone disease continued to lose weight. Five other patients (group 14), biochemically similar to group 1 but with shorter prior dialysis experience, who received EAA (plus glucose) hyperalimentation (including oral I-histidine), experienced weight gain similar to group 1 but displayed significantly different plasma aminograms indicating a deficit of NEAA. When EAA and glucose hyperalimentation was administered without histidine (1 patient) no weight gain occurred and aminograms differed significantly from other groups. Plasma aminograms of 25 weight-stable, nonhyperalimented CDT patients were obtained for comparison. Results indicate GAA hyperalimentation can promote weight gain in catabolic CDT patients with inadequate prior nutritional intake (as in groups 1 and 14) but cannot reverse weight loss when the primary clinical setting is advanced metabolic bone disease and myopathy due to hyperparathyroidism (group 2). Hyperalimentation with glucose and an amino acid solution specifically tailored to the needs of CDT patients may improve results. Plasma phosphoethanolamine levels, normal for weight-stable and elevated in catabolic CDT patients, suggest a possible role for phosphoethanolamine as a marker for catabolism.     

High plasma citrulline and arginine levels ensured by sustained-release citrulline supplementation in rats

ObjectiveDietary-supplemented arginine has been shown to have positive effects on cardiovascular disease, but several drawbacks exist and could potentially be avoided by using L-citrulline, since it is recycled to L-arginine. However, citrulline is very rapidly metabolized. We therefore developed a sustained-release form of citrulline and evaluated its metabolic behavior in rats.MethodsMale Sprague Dawley rats were divided into three groups: receiving “empty microcapsule” (control group), 1 g/kg/d immediate-release citrulline (IR citrulline group), or 1 g/kg/d sustained-release citrulline (SR citrulline group). Citrulline was given each day at 9 a.m. after blood samples for 9 d, and on day 10, blood samples were drawn every 4 h to study the decrease in plasma amino acid concentrations.ResultsSR citrulline led to a sustained increase in citrullinemia and argininemia compared to IR citrulline, and on day 6 argininemia was significantly (P < 0.01) higher with SR compared to IR citrulline. Moreover, argininemia was significantly higher in the SR citrulline group than in controls throughout the study and SR citrulline maintained high argininemia and citrullinemia, at least over 12 h.ConclusionThis experimental study provides a strong rationale for using this new formulation for atherosclerosis treatment.