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Introduction: High concentrations of trace elements (TE), in particular zinc and selenium, along with carnitine, are often added to parenteral admixtures in paediatric patients on long-term Parenteral Nutrition (PN). We aim to evaluate whether lipid droplet diameters of these admixtures maintain the recommended range of 0.4-1.0 μm., Materials and Methods: Stability studies were carried out on six parenteral admixtures with carnitine, trace elements and electrolytes added in different amounts. Each admixture was formulated with five different lipid emulsions with or without fish oil. Analyses were performed at time 0 (t = 0) and 24, 48, 72, 96 (t = 96) hours after compounding. Droplet diameters were determined by Light Scattering-Reverse Fourier Optics Technique. Samples, stored at 4 °C, were triple tested for a total of 450 analyses. Regression analyses were performed using panel-data techniques., Results: During the 4 days, lipid droplet diameters were in the expected range of 0.4-1.0 μm regardless of trace element and carnitine amounts in all admixtures apart from those containing fish-oil based emulsions and calcium concentrations equal to 4.5 mmol/L. In these latter admixtures, 12% of droplet diameters were larger than 1.0 μm and 2% exceeded 5.0 μm immediately after compounding., Conclusion: Carnitine and high concentrations of trace elements do not affect PN admixtures stability and can be safely infused in long-term home-PN paediatric patients and prematures. Only high calcium concentrations in compresence with fish oil based lipid emulsions seem to change PN stability., (Copyright © 2018 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.)

Background & Aims: Because lipid putatively encourages contaminant growth it has been proposed that infusion of lipid-containing parenteral nutrition (PN) bags should be restricted to 24 h (48 h or longer if lipid free). This study aimed to examine this proposal by identifying factors affecting Candida albicans growth in PN., Methods: C. albicans growth was assessed in quadruplicate in 12 PN infusates, with and without lipid and varying glucose concentrations., Results: The results are presented as mean ± SEM. Baseline log10 colony forming units (cfu)/mL (1.806 ± 0.015) increased substantially by 48 h in the PN infusates (to 3.731 ± 0.059). In PN infusates (pH 6.14 ± 0.01) growth was unaffected by the presence of 5% w/v lipid (0.246 ± 0.156 log10 cfu/mL decrease; P = 0.127), and independently suppressed by increasing glucose concentration (0.438 ± 0.174 log10 cfu/mL decrease per 10% increase in w/v glucose; P = 0.018). In a separate analysis growth was suppressed by increasing energy density (0.520 ± 0.179 log10 cfu/mL decrease per 1000 kcal non-nitrogen energy in 2 L; P = 0.007), without a significant effect of % non-nitrogen energy from lipid (0.056 ± 0.036 log10 cfu/ml increase per 10%; P = 0.082)., Conclusions: Using a framework developed to examine growth of potential contaminants in PN, the inclusion of lipid emulsion in PN produced no specific effect on the growth of C. albicans, other than by increasing energy density. Growth was independently suppressed by increasing either glucose concentration or non-nitrogen energy density., (Copyright © 2013 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.)

Background & Aims: Recommendations limit infusion of parenteral nutrition (PN) from bags with lipid to 24 h (48 h if lipid free) because lipid putatively encourages contaminant growth. This study aimed to examine these recommendations and identify factors affecting Staphylococcus epidermidis growth in PN., Methods: S. epidermidis growth was assessed in quadruplicate in 12 PN regimens, with and without lipid and varying glucose concentrations., Results: Baseline colony forming units (cfu)/mL (32.6) less than doubled at 48 h in all infusates. In PN infusates (pH 6.2 + 0.02 (SEM)) growth was independently increased by the presence of 5% w/v lipid (14.2 cfu/mL; P = 0.028), and glucose concentration (25.6 cfu/mL per 10% increase in w/v glucose; P = 0.003). In a separate analysis growth was stimulated by energy density (27.7 cfu/1000 kcal non-nitrogen energy in 2 L; P = 0.002), without a significant effect of % non-protein energy from lipid (-2.6 cfu/ml per 10%)., Conclusions: Using a framework developed to examine growth of potential contaminants in PN, no evidence was found to support the specific recommendation to restrict the maximum infusion duration of lipid containing PN to a greater extent than lipid free PN. S. epidermidis growth was not only affected by the presence of lipid, but also glucose concentration and energy density., (Copyright © 2012 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.)