Calcium and phosphorus retention in the preterm infant during total parenteral nutrition. A comparative randomised study between organic and inorganic phosphate as a source of phosphorus

Sodium Glycerophosphate Use in Parenteral Nutrition Improves Mineral Metabolism in Extremely Low Birth Weight Infants

OBJECTIVE

To evaluate the clinical effect of sodium glycerophosphate (NaGP) in parenteral nutrition solutions on mineral metabolism in extremely low birth weight (ELBW) infants.

STUDY DESIGN

NaGP was introduced for use in place of potassium phosphate (K₃PO₄) in January 2018; this retrospective cohort study included 95 ELBW infants treated with K₃PO₄ between January 2015 and December 2017 and 77 infants treated with NaGP between August 2018 and January 2021. Mineral intake over the first 14 days; changes in serum calcium, phosphorus, sodium, and alkaline phosphatase (ALP) levels over the first 1-3 months; and the rates of electrolyte imbalance and clinical morbidity were compared. High-risk infants who had nil per os (NPO) status for >14 days and prolonged parenteral nutrition exposure were further analyzed as a subgroup.

RESULTS

The use of NaGP instead of K₃PO₄ significantly increased Ca and P intake, but intakes remained below the recommended range (Ca, 64-140 mg/kg/day; P, 50-108 mg/kg/day). Compared with levels in the K₃PO₄ group, the NaGP group had significantly higher serum Ca and P levels after day 14 and lower ALP levels after day 56. In the subgroup analysis, the NaGP group had significantly lower incidences of hypophosphatemia, hyponatremia, bronchopulmonary dysplasia, and ALP >500 IU/L.

CONCLUSIONS

Although the administration of NaGP instead of K₃PO₄ in parenteral nutrition regimens still did not provide adequate Ca and P intake for ELBW infants, higher intake significantly improved serum Ca and P levels, especially in ELBW infants with prolonged parenteral nutrition exposure.

Standardised neonatal parenteral nutrition formulations - Australasian neonatal parenteral nutrition consensus update 2017

BACKGROUND

The first consensus standardised neonatal parenteral nutrition formulations were implemented in many neonatal units in Australia in 2012. The current update involving 49 units from Australia, New Zealand, Singapore, Malaysia and India was conducted between September 2015 and December 2017 with the aim to review and update the 2012 formulations and guidelines.

METHODS

A systematic review of available evidence for each parenteral nutrient was undertaken and new standardised formulations and guidelines were developed.

RESULTS

Five existing preterm Amino acid-Dextrose formulations have been modified and two new concentrated Amino acid-Dextrose formulations added to optimise amino acid and nutrient intake according to gestation. Organic phosphate has replaced inorganic phosphate allowing for an increase in calcium and phosphate content, and acetate reduced. Lipid emulsions are unchanged, with both SMOFlipid (Fresenius Kabi, Australia) and ClinOleic (Baxter Healthcare, Australia) preparations included. The physicochemical compatibility and stability of all formulations have been tested and confirmed. Guidelines to standardise the parenteral nutrition clinical practice across facilities have also been developed.

CONCLUSIONS

The 2017 PN formulations and guidelines developed by the 2017 Neonatal Parenteral Nutrition Consensus Group offer concise and practical instructions to clinicians on how to implement current and up-to-date evidence based PN to the NICU population.

Review of micronutrients in parenteral nutrition for the NICU population

A recent review of macronutrients in parenteral nutrition (PN) in the NICU population summarized the carbohydrate, protein, and fat nutrients in PN.1 The purpose of this article is to review the other nutrients in PN that are important for growth and homeostasis including minerals or electrolytes, vitamins, and trace elements. Although the macronutrients contribute more dramatically to adequate nutrition and growth, the other components in PN have significant impact on use of macronutrients as well as targeted organ and cellular function.

Standardised neonatal parenteral nutrition formulations - an Australasian group consensus 2012

Standardised parenteral nutrition formulations are routinely used in the neonatal intensive care units in Australia and New Zealand. In 2010, a multidisciplinary group was formed to achieve a consensus on the formulations acceptable to majority of the neonatal intensive care units. Literature review was undertaken for each nutrient and recommendations were developed in a series of meetings held between November 2010 and April 2011. Three standard and 2 optional amino acid/dextrose formulations and one lipid emulsion were agreed by majority participants in the consensus. This has a potential to standardise neonatal parenteral nutrition guidelines, reduce costs and prescription errors.

Chemical stability study of vitamins thiamine, riboflavin, pyridoxine and ascorbic acid in parenteral nutrition for neonatal use

BACKGROUND

The objective of this work was to study the vitamins B1, B2, B6 and C stability in a pediatric formulation containing high amounts of calcium in the presence of organic phosphate, amino acids, glucose, sodium chloride, magnesium sulfate, pediatric vitamins and trace elements under different conditions using developed and validated analytical methods.

METHODS

The study was carried out during 72 h with formulations packaged in recommended storage temperature (4°C) and 25°C, with and without photoprotection.

RESULTS

The results showed that the methodologies used for assessing the chemical stability of vitamins B1, B2, B6 and C in the formulation were selective, linear, precise and accurate. The vitamins could be considered stable in the formulation during the three days of study if stored at 4°C. When stored at 25°C vitamin C presented instability after 48 h.

CONCLUSION

The pediatric formulation containing high amount of calcium in the presence of organic phosphate, amino acids, glucose, sodium chloride, magnesium sulphate, pediatric vitamins and trace elements packaged in bag-type trilaminate presented a shelf life of the 72 h, when maintained under refrigeration, between 2°C and 8°C. This shelf life was measured considering the vitamins studied. Further studies are needed including all the vitamins present in this formulation.

Influence of the calcium concentration in the presence of organic phosphorus on the physicochemical compatibility and stability of all-in-one admixtures for neonatal use

BACKGROUND

Preterm infants need high amounts of calcium and phosphorus for bone mineralization, which is difficult to obtain with parenteral feeding due to the low solubility of these salts. The objective of this study was to evaluate the physicochemical compatibility of high concentrations of calcium associated with organic phosphate and its influence on the stability of AIO admixtures for neonatal use.

METHODS

Three TPN admixture formulas were prepared in multilayered bags. The calcium content of the admixtures was adjusted to 0, 46.5 or 93 mg/100 ml in the presence of a fixed organic phosphate concentration as well as lipids, amino acids, inorganic salts, glucose, vitamins and oligoelements at pH 5.5. Each admixture was stored at 4 degrees C, 25 degrees C or 37 degrees C and evaluated over a period of 7 days. The physicochemical stability parameters evaluated were visual aspect, pH, sterility, osmolality, peroxide formation, precipitation, and the size of lipid globules.

RESULTS

Color alterations occurred from the first day on, and reversible lipid film formation from the third day of study for the admixtures stored at 25 degrees C and 37 degrees C. According to the parameters evaluated, the admixtures were stable at 4 degrees C; and none of them presented precipitated particles due to calcium/phosphate incompatibility or lipid globules larger than 5 mum, which is the main parameter currently used to evaluate lipid emulsion stability. The admixtures maintained low peroxide levels and osmolarity was appropriate for parenteral administration.

CONCLUSION

The total calcium and calcium/phosphorus ratios studied appeared not to influence the physicochemical compatibility and stability of AIO admixtures.