Influence of vitamins, trace elements, and iron on lipid peroxidation reactions in all-in-one admixtures for neonatal parenteral nutrition

Background: The purpose of this study was to evaluate the effect of vitamins, trace elements, or iron on lipid peroxidation in all‐in‐one parenteral nutrition (PN) admixtures for preterm neonates. Methods: Malondialdehyde (MDA) concentrations were analyzed over a 24‐hour period (H1‐H24) in lipid‐containing PN solutions that have a composition identical to that used in the routine clinical care of preterm infants. Six different solutions were prepared and evaluated when exposed to ambient light and light‐protected conditions as follows: control (without vitamins [Vit], trace elements [TE], or iron [Fe] [Vit?TE?Fe?]), solution 1 (Vit+TE+Fe?), solution 2 (Vit+TE?Fe?), solution 3 (Vit?TE+Fe?), solution 4 (Vit?TE?Fe+), and solution 5 (Vit+TE+Fe+). Results: MDA concentrations in PN solutions were significantly higher at H24 than at H0 when they contained multivitamins (P < .001), trace elements (P = .002), or iron saccharate (P = .018). MDA concentration was particularly high when all 3 micronutrients were present (P < .001) or when the solutions were exposed to ambient light. In solutions containing iron, MDA concentrations were elevated at H0, and levels did not change whether protected from (P < .001) or exposed to (P < .001) from light. Conclusions: The addition of vitamins and trace elements to PN solutions induces a significant increase in peroxidation products, which are lowered when admixtures are protected from light. Iron should not be included in these solutions, even if solutions are light‐protected. By following these conditions it is possible to use all‐in‐one admixtures in the nutrition management of preterm infants.     

Addition of Insulin to Parenteral Nutrition for Control of Hyperglycemia

Administration of parenteral nutrition (PN) may result in hyperglycemia in patients with preexisting diabetes or disease‐related insulin resistance, and it can be associated with increased rates of complications. Treatment requires insulin therapy. Insulin can be administered subcutaneously, intravenously via a variable rate sliding scale, or by adding it directly to the PN. The last method is a potentially attractive technique for a number of reasons—it could deliver the insulin intravenously at a steady rate alongside carbohydrates, and in malnourished patients with little subcutaneous tissue, it may prevent the need for frequent insulin injections. Despite such potential advantages, the addition of insulin to PN remains controversial, largely with respect to the bioavailability of insulin in PN and resultant concerns of the risk of hypoglycemia. There is a paucity of long‐term quality controlled studies to address this question. The available literature suggests that, at least in the short term, insulin addition to PN can achieve reasonable glycemic control with low rates of hypoglycemia, and the technique compares favorably with the use of long‐acting insulin preparations. This literature review finds a wide range of values reported for insulin availability via PN, ranging from 44% to 95% depending on the type of PN container material used and the presence of added vitamins and trace elements. Few studies looking at glycemic control among patients receiving home PN were found, and larger prospective trials are needed to assess the efficacy and safety of this technique in this patient group.     

Anemia and Leukopenia in a Long‐Term Parenteral Nutrition Patient During a Shortage of Parenteral Trace Element Products in the United States

Recently, drug shortages in the United States have affected multiple components of the parenteral nutrition (PN) solution. A 62‐year‐old patient with systemic sclerosis who was dependent on home PN due to intestinal dysmotility developed anemia and leukopenia approximately 4 months after parenteral copper was withheld from her PN solution due to drug shortages. The patient was not able to tolerate a sufficient amount of oral multivitamins with trace elements due to severe dysphagia. Her serum copper and ceruloplasmin concentrations were undetectable, confirming the diagnosis of severe copper deficiency. The hematological abnormalities promptly resolved with copper supplementation. This report emphasizes the importance of close monitoring for nutrient deficiencies during drug shortages and supplementing with oral or enteral nutrition when feasible, particularly in high‐risk patients such as those with intestinal malabsorption or short bowel syndrome who are dependent on long‐term PN.     

Application of refractometry to quality assurance monitoring of parenteral nutrition solutions

Parenteral nutrition (PN) solution contains various concentrations of dextrose, amino acids, lipids, vitamins, electrolytes, and trace elements. Incorrect preparation of PN solution could lead to patient death. In this study we used the refractive index as a quality assurance tool to monitor the preparation of PN solution. Refractive indices of single nutrient components and PN solutions consisting of various concentrations of dextrose, amino acids, electrolytes, and lipids were measured. A mathematical equation and its linear plot were generated then used to predict the refractive index of the PN solution. The best-fit refractive index for PN solution (i.e., the predicted refractive index)=0.9798x(% dextrose)+1.2889x(% amino acids)+1.1017x(% lipids)+0.9440x(% sum of the electrolytes)+0.5367 (r2=0.99). This equation was validated by comparing the measured refractive indices of 500 clinical PN solutions to their predicted refractive indices. We found that 2 of the 500 prepared samples (0.4%) had less than the predicted refractive index (<95%). Refractive index can be used as a reliable quality assurance tool for monitoring PN preparation. Such information can be obtained at the bedside and used to confirm the accuracy of the PN solution composition.     

Computer‐Assisted Glucose Regulation During Rapid Step‐Wise Increases of Parenteral Nutrition in Critically Ill Patients

Background: Early delivery of calories is important in critically ill patients, and the administration of parenteral nutrition (PN) is sometimes required to achieve this goal. However, PN can induce acute hyperglycemia, which is associated with adverse outcome. We hypothesized that initiation of PN using a rapid “step‐up” approach, coupled with a computerized insulin‐dosing protocol, would result in a desirable caloric intake within 24 hours without causing hyperglycemia. Methods: In our surgical intensive care unit (ICU), glucose is regulated by a nurse‐centered computerized glucose regulation program. When adequate enteral feeding was not possible, PN was initiated according to a simple step‐up rule at an infusion rate of 10 mL/h (approximately 10 kcal/h) and subsequently increased by steps of 10 mL/h every 4 hours, provided glucose was <10 mmol/L, until the target caloric intake (1 kcal/kg/h) was reached. All glucose levels and insulin doses were collected during the step‐up period and for 24 hours after achieving target feeding. Results: In all 23 consecutive patients requiring PN, mean intake was 1 kcal/kg/h within 24 hours. Of the 280 glucose samples during the 48‐hour study period, mean ± standard deviation glucose level was 7.4 ± 1.4 mmol/L. Only 4.5% of glucose measurements during the step‐up period were transiently ≥10 mmol/L. After initiating PN, the insulin requirement rose from 1.1 ± 1.5 units/h to 2.9 ± 2.5 units/h (P < .001). Conclusions: This proof of concept study shows that rapid initiation of PN using a step‐up approach coupled with computerized glucose control resulted in adequate caloric intake within 24 hours while maintaining adequate glycemic control.     

Sleep patterns of cyclic parenteral nutrition,a pilot study: are there sleepless nights?

BACKGROUND: Cyclic home parenteral nutrition (HPN) is 1 of the few medical therapies given during normal nocturnal sleep hours, and it is possible that infusion may alter normal sleep patterns. The aim of this pilot study was to evaluate the sleep patterns of 5 patients receiving HPN. METHODS: An Epworth sleep questionnaire was completed and wrist Actigraph data were collected before admission to the sleep laboratory. Formal overnight polysomnography was then preformed for 3 consecutive nights. The first night served as the acclimatization period. On the second and third nights, patients were randomized to receive either no infusion or infusion of their standard parenteral nutrition. Results were reported as the median and range and were compared with historical aged-matched controls. RESULTS: Five patients (3 women and 2 men) with a mean age of 61 years (40 to 73 years) were studied. Patients had been HPN-dependent for a median of 23 months (4 to 60 months). Patients were receiving HPN because of short bowel syndrome (2), chronic pancreatitis (2), and intestinal pseudoobstruction (1). A 1.5-liter HPN formula, infused over 10 hours, included approximately 25 kcal/kg/d with 30% lipid and 1.0 to 1.5 g/kg/d of protein. All solutions included multiple trace elements and standard multivitamins. During total parenteral nutrition (TPN) infusion, the percent of sleep efficiency was higher than without infusion, 81% versus 72%. Sleep efficiency in age-matched controls was approximately 88%. Sleep latency was longer in patients compared with controls, and longer in patients during infusion than without infusion, 35 versus 28 minutes. During TPN infusion, the percent of stage-1 (2%), stage-2 (52%), slow-wave (24%) and random eye movement (REM) sleep (21%) was similar to values during the night without infusion. Controls had lower slow-wave and REM times. The median Epworth sleep score was 3, which is the normal reported range. CONCLUSIONS: Although sleep quality is reduced in patients receiving HPN compared with aged-matched controls, sleep quality does not seem to be negatively effected by cyclic HPN infusion.     

Intraoperative infusion of acetated Ringer solution containing glucose and ionized magnesium reduces ketogenesis and maintains serum magnesium

The effect of glucose infusion during surgery on glucose metabolism has not been investigated sufficiently. We, therefore, examined the effect after the infusion of 1% glucose acetated Ringer solution containing Mg2+ during surgery on ketogenesis and serum Mg2+ concentrations. Patients, classified as ASA I-II, age 51-80 years, were randomly assigned to receive infusion of acetated Ringer solution. The G/Mg group received infusion with 1% glucose, Na+ 140mEq/L, Mg2+ 2 mEq/L, and the C group received infusion with glucose free solution containing Na+ 130 mEq/L without Mg2+. Both solutions were infused at a rate of 25 mL/kg for the first hour, and main-tained at 4 mL/kg/hr thereafter. Blood samples were collected three times: before infusion and at 1 hour and 4 hours after the start of infusion. Electrolytes and glucose metabolism were evaluated at each sampling. After rapid infusion, blood glucose level significantly increased to 170+/-19mg/dL in the G/Mg group, but it returned to close to baseline after 4 hours and serum ketone bodies did not increase during infusion. In the C group, however, blood glucose never increased beyond 110 mg/dL, but both acetoacetic and hydroxybutyric acids increased significantly at the third measurement.     

Aluminum contamination of parenteral nutrition additives, amino acid solutions, and lipid emulsions.

Contamination of parenteral nutrition solutions with aluminum may result in accumulation of this element in bones and, in premature infants, may inhibit bone calcium uptake and induce cholestasis. We measured the aluminum concentration of small-volume parenterals, amino acid solutions, lipid emulsions, and special solutions containing glucose, amino acids, electrolytes, and trace elements (standard I for children with a body weight of 3-5 kg, standard II for children with a body weight of 5-10 kg). The method used was graphite furnace atomic absorption spectrometry GTA-AAS (SpectrAA-400 Plus, Varian, PtY Ltd., Mulgrave, Australia). Quality control was run with the use of control serum (Seronorm, Nycomed, Oslo, Norway). The aluminum contents of parenterally administered solutions were: pediatric trace elements, 130 micrograms/L, and pediatric trace elements, 3000 micrograms/L; phosphorus salts: K-phosphates, 9800 micrograms/L, and Na/K phosphates, 13,000 micrograms/L; 10% calcium gluconate, 4400 micrograms/L; 6.5% amino acids, 30 micrograms/L; 10% amino acids, 120 micrograms/L; 12.5% amino acids, 121 micrograms/L; 20% lipid emulsion, 30 micrograms/L; 20% lipid emulsion, 180 micrograms/L; water-soluble vitamins, 12 micrograms/L; lipid soluble vitamins, 360 micrograms/L; standard I, 55 micrograms/L; standard II, 90 micrograms/L; The aluminum intake from parenteral nutrition was 6.6-10.8 micrograms.kg-1.d-1--a dose exceeding the safety limit of 2 micrograms.kg-1.d-1. The possible association of aluminum not only with metabolic bone disease, but also with encephalopathy, dictates caution when dealing with the pediatric population on long-term parenteral nutrition. In the absence of reliable label information, it seems proper to monitor the aluminum concentration in parenteral nutrition products and to report it in professional journals.     

Predictors of Insulin Requirements Among Hospitalized Adults Receiving Parenteral Nutrition

Objective: The objective of this quality improvement project was to determine factors predictive of parenteral nutrition (PN) insulin therapy. Methods: Patients receiving PN at a tertiary care academic medical center between January 1, 2009, and December 1, 2012, 18 years or older were included. Variables collected included demographics, medical information, and PN‐specific data. χ² and Student t tests were used to determine differences between patients who did and did not require PN insulin. Odds ratios (ORs) with 95% confidence intervals (CIs) were used to determine associations between characteristics. Stepwise forward logistic regression was used determine the best predictors of PN insulin. Results: A total of 1388 patients were started on PN. After adjusting for potential confounders, strong associations existed between PN insulin requirements and diabetes mellitus (DM) diagnosis (OR, 8.90; 95% CI, 4.98–15.90, P < .001), overweight/obese status (body mass index ≥25.0 kg/m²) (OR, 2.12; 95% CI, 1.04–4.30, P = .04), intensive care unit (ICU) admission (OR, 1.79; 95% CI, 1.03–3.11, P = .04), blood glucose (BG) on day of PN start >120 mg/dL (OR, 2.32; 95% CI, 1.32–4.05, P = .003), mean BG >180 mg/dL while receiving PN (OR, 6.10; 95% CI, 2.18–17.04, P = .001), and hemoglobin A1c (A1c) ≥5.7% (OR, 3.18; 95% CI, 1.84–5.50, P < .001). Among variables available at PN initiation, DM diagnosis (P < .001), A1c ≥5.7% (P < .001), BG >120 mg/dL on PN start day (P < .001), and ICU admission (P < .001) predicted the need for PN insulin.     

Urticaria associated with parenteral nutrition

We report a 53-year-old female patient with short bowel syndrome who developed urticaria after administration of cyclic parenteral nutrition (PN). The urticaria occurred 2 hours into the 12-hour nocturnal infusion and resolved completely 1 hour after discontinuation of the PN infusion. The urticaria occurred despite removing lipids from the 3-in-1 PN solution. The urticaria did not occur when the multivitamin preparation was removed from the PN. Upon rechallenge with a PN solution containing a multivitamin, the urticaria reoccurred. Prick skin testing using the multivitamin in increasing aliquots was negative. Serum tryptase and 12-hour urinary histamine level during PN infusion containing the multivitamin was unchanged compared with baseline measurements. The patient had no allergic reaction using a similar dose of an oral multivitamin. This case illustrates that allergic reactions from PN infusion may occur and that the multivitamin preparation can be the cause.     

Availability of insulin from total parenteral nutrition solutions

Insulin is frequently required in total parenteral nutrition (TPN) solutions to control hyperglycemia. The purpose of this study was to evaluate the recovery of human insulin from standard TPN solutions with and without lipids and from TPN solutions with specialized amino acid formulations and to compare it to the insulin recovery from normal saline. All solutions were mixed in currently utilized PVC-free bags (ethylene vinyl acetate) and drained through PVC-containing tubing. Human insulin (Humulin-R) was spiked with 125I-labeled insulin and then added in concentrations of 10, 25, and 50 units to 1-liter bags containing 39-g amino acids (10% Freamine-III; or 6.9% Freamine HBC; or 8% Hepatamine), 257-g dextrose, electrolytes (Hyperlyte-R), 1000 units of heparin, MVI-12, and MTE-5 Concentrate. Alternate sets of bags contained 125 ml of 20% Intralipid and an appropriate amount of sterile water to keep the final volume at 1 liter. Actual clinical conditions of preparation, storage, and administration were simulated in this in vitro experiment. Multiple samples were collected during the 8-hr infusion period directly in gamma counter vials. All experiments and assays were done in triplicate. Our findings indicate that human insulin availability in TPN solutions is much higher (90%-95%) than the 50% suggested in the literature. Insulin recovery was not appreciably altered by adding lipids or by using Freamine HBC. Insulin recovery from TPN solutions was significantly reduced if they contained Hepatamine (87% and 88%, p less than 0.05) as compared to Freamine (90% and 94%).(ABSTRACT TRUNCATED AT 250 WORDS)     

The use of IV fat in neonates.

IV fat emulsion (IVFE) is an integral part of the parenteral nutrition (PN) regimen in neonates. It provides a concentrated isotonic source of calories and prevents or reverses essential fatty acid deficiency. Continuous administration of IV fat with PN regimens prolongs the viability of peripheral IV lines in infants who might have limited venous access. IVFE must be administered separately from the PN solution in neonates. The acidic pH of a PN solution is necessary for maximum solubility of calcium and phosphorus. If fat emulsion is added to the PN solution, as is done in 3-in-1 (total nutrient admixture) solutions, the high amount of calcium and phosphorus needed by these infants may result in an unseen precipitate with serious consequences. Continuous fat infusion over 24 hours is the preferred method in neonates. The administration rate of 0.15 g/kg/hour for IVFE in the neonate should not be exceeded. Essential fatty acid deficiency can be prevented in neonates by providing IVFE in a dose of 0.5-1.0 g/kg/day. Carnitine is not routinely required to metabolize IVFE in the neonate. Infants should receive 20% lipid emulsion to improve clearance of triglycerides and cholesterol. Serum triglyceride levels should be maintained at <150-200 mg/dL in neonates. There are concerns about potential adverse effects of early administration of IV fat in very-low-birth-weight infants weighing <800 g. We hold the IV fat dose at 1.0-1.5 g/kg/day until the second week of life in infants <30 weeks gestation.     

Total sulfur amino acid requirement and metabolism in parenterally fed postsurgical human neonates

BACKGROUND: Except for tyrosine, the amino acid requirements of human neonates receiving parenteral nutrition (PN) have not been experimentally derived. OBJECTIVES: The objectives were to determine the total sulfur amino acid (TSAA) requirement (methionine in the absence of cysteine) of postsurgical, PN-fed human neonates by using the indicator amino acid oxidation (IAAO) technique with L-[1-(13)C]phenylalanine as the indicator. DESIGN: Fifteen postsurgical neonates were randomly assigned to receive 1 of 18 methionine intakes ranging from 10 to 120 mg x kg(-1) x d(-1), delivered in a customized, cysteine-free amino acid solution. Breath and urine samples were collected for the measurement of (13)CO(2) and amino acid enrichment. Blood samples were collected at baseline and after the test methionine infusion for the measurement of plasma methionine, homocysteine, cystathionine, and cysteine concentrations. RESULTS: Breakpoint analysis determined the mean TSAA requirements to be 47.4 (95% CI: 38.7, 56.1) and 49.0 (95% CI: 39.9, 58.0) mg x kg(-1) x d(-1) with the use of oxidation and F(13)CO(2), respectively. CONCLUSIONS: This is the first study to report the TSAA requirement of postsurgical, PN-fed human neonates. The estimated methionine requirement expressed as a proportion of the methionine content of current commercial pediatric PN solutions was 90% (range: 48-90%) of that found in the lowest methionine-containing PN solution.     

Case report of an allergic reaction to parenteral nutrition in a pediatric patient

We report a 34-month-old girl with stage IV neuroblastoma who developed hives when parenteral nutrition (PN) containing amino acids, dextrose, electrolytes, minerals, vitamins, and trace elements was infused. Administration of diphenhydramine resulted in disappearance of the rash. Infusion of the PN solution without intravenous fat emulsion produced a similar rash with itching. The pediatric multiple vitamin (PMV) preparation was removed from the PN formula and the formula was infused without incident. The patient was maintained on PN and an oral vitamin supplement with no further complaints. Inadvertent administration of a PN solution containing PMV resulted in a recurrence of hives. Absence of any adverse reactions when the PMV preparation was removed from the PN solution and an allergic reaction when the multivitamin was added to the PN solution support the possibility that the allergic reaction was related to the infusion of the multiple vitamin preparation.     

Glargine Insulin Use Versus Continuous Regular Insulin in Diabetic Surgical Noncritically Ill Patients Receiving Parenteral Nutrition: Randomized Controlled Study

Background: Hyperglycemia is a major complication of parenteral nutrition (PN). Guidelines for hyperglycemia management in noncritically ill patients cite basal insulin administration but do not recommend a regimen. The GLUCOSE‐in‐PN study aimed to compare the efficacy of glargine insulin versus continuously infused regular insulin in PN (RI‐in‐PN) to achieve glycemic control in noncritically ill surgical patients with diabetes who were receiving PN. Methods: This prospective randomized open‐label study was conducted at King Faisal Specialist Hospital and Research Centre. Noncritically ill surgical patients with diabetes who were receiving PN were randomized to receive basal glargine insulin or RI‐in‐PN on day 4 of PN support. Mean blood glucose levels were compared on study days 5–9. The percentages of blood glucose measurements at goal were compared between groups. Results: Sixty‐seven PN treatment episodes were analyzed. There were no statistically significant differences in mean glucose levels between groups on any study day (P > .1). Overall glycemic control rates were 52.24% (glargine insulin) and 47.76% (RI‐in‐PN; P = .06). A significantly higher percentage of hyperglycemia was observed on day 5 for glargine insulin versus RI‐in‐PN (22.39% vs 5.97%, P = .0059). Blood glucose measurements indicated 6 hypoglycemic events: 2 for glargine insulin (5.7%) and 4 for RI‐in‐PN (11.4%; P > .1). Conclusion: Both glargine insulin and RI‐in‐PN are effective basal insulin modalities for blood glucose control in noncritically ill surgical patients with diabetes who are receiving PN. Uncontrolled hyperglycemic events occurred more frequently with glargine insulin, and the rate of hypoglycemia was acceptable for both regimens.     

Trace element contamination of total parenteral nutrition. 1. Contribution of component solutions.

BACKGROUND: Trace elements have been shown to contaminate total parenteral nutrition (TPN) solutions. METHODS: This study used the multi-elemental technology of inductively coupled plasma-mass spectrometry to demonstrate the extent to which trace elements were present in amounts above (ie, as contaminants) or below expected levels in eight TPN component solutions. RESULTS: Of the 66 trace elements scanned, there were 12 trace element contaminants in amounts >1 microg/L (zinc, copper, manganese, chromium, selenium, boron, aluminum, titanium, barium, vanadium, arsenic, and strontium) in the eight component solutions studied. Trace element contaminants were present in all solutions, and different trace elements contaminated the solutions at various concentrations. Component solutions of amino acid, potassium chloride, calcium gluconate, and sodium chloride contained the greatest numbers of trace element contaminants, whereas the lowest numbers were present in sterile water and magnesium sulfate. Interlot and intermanufacturer variations were apparent. Measured concentrations of trace elements in the multi-trace element additive solution also were higher than the labeled values. A comparison of the amounts of contaminated trace elements delivered by a typical TPN mixture relative to the amounts typically absorbed by the gastrointestinal tract indicates that the inadvertent delivery of trace elements from contaminated TPN solutions may be substantial. CONCLUSIONS: All eight components tested were contaminated with trace elements not intended to be present in the product, and similarly, the multi-trace element component contained trace elements either above or below that which the label claimed.     

Association between the intake of vitamins and trace elements from supplements and C-reactive protein: results of the MONICA/KORA Augsburg study

OBJECTIVE: To examine the association between plasma concentrations of C-reactive protein (CRP) and the intake of vitamins and trace elements from supplements possibly related to inflammation such as vitamin C, vitamin E, carotenoids, selenium and zinc. DESIGN: Cross-sectional study using data from the Monitoring of Trends and Determinants in Cardiovascular Disease/Cooperative Health Research in the Region of Augsburg (MONICA/KORA) Survey 1994/95. SETTING: Region of Augsburg, Southern Germany. SUBJECTS: Population-based sample of 2045 women and 2172 men, aged 25-74 years. RESULTS: Intake of dietary supplements containing vitamins and trace elements was associated with lower CRP levels in women. Especially vitamin E in combination with other vitamins like vitamin C, vitamin B(1), B(2), B(6), B(12), niacin, folic acid, pantothenic acid and selenium, was significantly associated with lower CRP levels. Odds ratios for elevated CRP levels (>3.0 mg/l) after multivariable adjustment were 0.57 (95% confidence interval (CI): 0.37, 0.89) for the intake of vitamin E and 0.57 (95% CI: 0.35, 0.91) for the intake of multivitamins, defined as taking three or more different vitamins. These associations were not seen in men. Intake of vitamin C, carotenoids or zinc was not significantly associated with levels of CRP in both men and women. CONCLUSIONS: Our data indicate that the intake of certain vitamins and trace elements from supplements is associated with lower CRP concentrations in women. Thus, intake of these micronutrients could influence the inflammatory process underlying the pathogenesis of atherosclerosis. Specific dose response relationships and the best combinations of vitamins and trace elements have to be determined in further studies.     

Effect of parenteral glutamine supplementation on plasma amino acid concentrations in extremely low-birth-weight infants

BACKGROUND: Glutamine is one of the most abundant amino acids in both plasma and human milk and may be conditionally essential in premature infants. However, glutamine is not provided by standard intravenous amino acid solutions. OBJECTIVE: We assessed the effect of parenteral glutamine supplementation on plasma amino acid concentrations in extremely low-birth-weight infants receiving parenteral nutrition (PN). DESIGN: A total of 141 infants with birth weights of 401-1000 g were randomly assigned to receive a standard intravenous amino acid solution that did not contain glutamine or an isonitrogenous amino acid solution with 20% of the total amino acids as glutamine. Blood samples were obtained just before initiation of study PN and again after the infants had received study PN (mean intake: 2.3 +/- 1.0 g amino acids x kg(-1) x d(-1)) for approximately 10 d. RESULTS: Infants randomly assigned to receive glutamine had mean plasma glutamine concentrations that increased significantly and were approximately 30% higher than those in the control group in response to PN (425 +/- 182 and 332 +/- 148 micromol/L for the glutamine and control groups, respectively). There was no significant difference between the 2 groups in the relative change in plasma glutamate concentration between the baseline and PN samples. In both groups, there were significant decreases in plasma phenylalanine and tyrosine between the baseline and PN samples; the decrease in tyrosine was greater in the group that received glutamine. CONCLUSIONS: In extremely low-birth-weight infants, parenteral glutamine supplementation can increase plasma glutamine concentrations without apparent biochemical risk. Currently available amino acid solutions are likely to be suboptimal in their supply of phenylalanine, tyrosine, or both for these infants.     

Parenteral nutrition-induced hypersensitivity in an adolescent

A case report of a 15-year-old adolescent male who developed a hypersensitivity reaction to a parenteral nutrition (PN) solution containing multivitamins (MVI) is presented. Within 30 minutes after initiation of PN and lipids, the patient developed a total-body pruritic urticarial rash that resolved after discontinuation of the infusions and administration of diphenhydramine. Rechallenge with the same PN solution excluding heparin, as well as lipids, resulted in a similar urticarial reaction that also resolved within 30 minutes after discontinuation of the infusions and administration of diphenhydramine. Another rechallenge with a solution containing dextrose and amino acids at the same concentrations contained in the original PN solution did not elicit an allergic reaction, whereas addition of MVI to the dextrose and amino acids resulted in a similar allergic reaction 20 minutes after the start of the infusion. It was determined that the MVI component of the PN was the most likely causative agent of this patient's urticarial reaction.