Calcium chloride in neonatal parenteral nutrition: compatibility studies using laser methodology

Select micronutrients for the preterm neonate

If premature neonates are not provided with adequate nutrition, they will quickly become deficient because of increased requirements and a lack of nutrient stores to achieve adequate growth. The provision of many of the recommended micronutrients for pediatric and adult patients is challenging in premature neonates because of the limited data surrounding the true needs of premature neonates and the difficulty in assessing adequate serum levels of these nutrients in this patient population. Parenteral and enteral nutrition shortages further complicate providing adequate micronutrients to premature neonates. This review will discuss select micronutrients and their importance to the preterm neonate, with special emphasis on micronutrients with limited evidence and more challenging supplementation and repletion strategies.

Calcium/Phosphate Solubility Curves for Premasol and Trophamine Pediatric Parenteral Nutrition Formulations

OBJECTIVES

Calcium and phosphate incompatibility in parenteral nutrition formulations remains a critical concern for patient safety. This study examined calcium phosphate solubility for 2-in-1 admixtures prepared using 2 commercially available pediatric amino acid solutions (Premasol, Baxter Healthcare Corp; or Trophamine, B. Braun Medical Inc), applying identical test methods, storage conditions, and acceptance criteria.

METHODS

Parenteral 2-in-1 admixtures included amino acid; dextrose; static concentrations of sodium, potassium, and magnesium, and varying concentrations of calcium (0-60 mEq/L), phosphate (15-50 mmol/L), and cysteine. Three replicate samples were stored for 48 hours at 40°C ± 2°C and then visually inspected for particulate matter, evaluated for subvisible particulate matter, when particulate matter was noted, microscopic examination was performed to confirm the presence of calcium phosphate crystals. Pass criteria were: all replicates free of visible particulate matter related to calcium phosphate crystals and particle counts below US Pharmacopeia <788> limits.

RESULTS

Premasol and Trophamine generated identical calcium phosphate curves for 2% amino acid formulations containing 20% dextrose with/without cysteine, and similar curves for the 1% or 3% amino acid formulations containing 10% or 20% dextrose with/without cysteine. Calcium phosphate particles were identified in failed samples by scanning electron microscopy/energy dispersive X-ray spectroscopy. Calcium phosphate solubility was higher in formulations containing cysteine 40 mg/g amino acid vs. cysteine 20 mg/g amino acid and in cysteine 20 mg/g amino acid vs. no cysteine.

CONCLUSIONS

Admixtures made with 1%, 2%, or 3% Premasol or Trophamine have essentially equivalent calcium phosphate solubility curves when tested with identical methods, storage conditions, and acceptance criteria.

Calcium Chloride and Calcium Gluconate in Neonatal Parenteral Nutrition Solutions with Added Cysteine: Compatibility Studies Using Laser Light Obscuration Methodology

BACKGROUND

Parenteral nutrition (PN) solutions containing calcium gluconate (CaGlu) and cysteine have elevated particle counts when analyzed using laser light obscuration (LO) as recommended by the United States Pharmacopeia (USP). There are no compatibility studies for solutions compounded with cysteine and containing calcium chloride (CaCl₂ ) using LO. The purpose of this study was to conduct compatibility testing for neonatal PN solutions containing CaCl₂ and CaGlu with cysteine.

METHODS

Solutions of amino acids (2.5%), containing either CaCl₂ or CaGlu plus potassium phosphate, were compounded with 50 and 100 mg/dL cysteine. Solutions were analyzed for particle counts using LO. Maximum concentrations tested were 20 mmol/L calcium and 15 mmol/L phosphate. Three solutions containing CaCl₂ (144 total solutions) and 2 containing CaGlu (96 total solutions) and the same concentration of additives were compounded. If the average particle count of replicates exceeded USP guidelines, the solution was incompatible.

RESULTS

All solutions containing CaGlu had particle counts that exceeded USP guidelines for particle counts ≥10 μm (range, 86-580 particles/mL). For CaCl₂ , 90 of 144 solutions were compatible (range of particle counts for all solutions, 3-121 particles/mL). Maximum compatible concentrations of CaCl₂ and potassium phosphate were 15 mmol/L and 12.5 mmol/L, respectively, for solutions containing both 50 and 100 mg/dL cysteine.

CONCLUSION

This study found that neonatal PN solutions containing CaGlu with added cysteine have significantly higher particle counts, exceeding USP guidelines for compatibility, than those containing CaCl₂ .

Calcium Chloride and Calcium Gluconate in Neonatal Parenteral Nutrition Solutions without Cysteine: Compatibility Studies Using Laser Light Obscuration Methodology

There are no compatibility studies for neonatal parenteral nutrition solutions without cysteine containing calcium chloride or calcium gluconate using light obscuration as recommended by the United States Pharmacopeia (USP). The purpose of this study was to do compatibility testing for solutions containing calcium chloride and calcium gluconate without cysteine. Solutions of TrophAmine and Premasol (2.5% amino acids), containing calcium chloride or calcium gluconate were compounded without cysteine. Solutions were analyzed for particle counts using light obscuration. Maximum concentrations tested were 15 mmol/L of calcium and 12.5 mmol/L of phosphate. If the average particle count of three replicates exceeded USP guidelines, the solution was determined to be incompatible. This study found that 12.5 and 10 mmol/L of calcium and phosphate, respectively, are compatible in neonatal parenteral nutrition solutions compounded with 2.5% amino acids of either TrophAmine or Premasol. There did not appear to be significant differences in compatibility for solutions containing TrophAmine or Premasol when solutions were compounded with either CaCl₂ or CaGlu-Pl. This study presents data in order to evaluate options for adding calcium and phosphate to neonatal parenteral nutrition solutions during shortages of calcium and cysteine.

Calcium chloride in neonatal parenteral nutrition: A 15 year experience

OBJECTIVE

The objective of this study was to determine if outcomes at our neonatal intensive care units (NICUs) since we began using calcium chloride (CaCl2) as our preferred calcium additive in order to reduce aluminum (Al) exposure are within expected outcome ranges for NICUs in the U.S. where calcium gluconate in glass vials (CaGlu-Gl) has been the preferred additive.

STUDY DESIGN

A retrospective study of very low birth weight infants born between January 1, 2000 and December 31, 2014. Outcomes in two intensive care units (NICUs) using CaCl2 were compared to all U.S. NICUs in the Vermont Oxford Network. Primary outcomes were chronic lung disease (CLD), percent requiring supplemental oxygen at 28 days, and mortality excluding early deaths (MEED). The incidence of IV infiltrates of all admissions to the study NICUs in 2013-2014 was compared to the literature.

RESULTS

The incidence of CLD and those requiring oxygen at 28 days were 24.0% vs 28.6% and 46.2% vs 51.8% for the study NICUs compared to all U.S. NICUs, respectively (both p < 0.0001). The MEED was 8.7% vs 10.3% (p < 0.002). All major morbidities were lower at the study NICUs. The incidence of infiltrates was lower than that in the literature.

CONCLUSION

The use of CaCl2 was not associated with any detectable adverse effects. Calcium chloride appears to be a safe alternative to the use of CaGlu-Gl based upon studies of clinical outcomes.

Aluminum Content of Neonatal Parenteral Nutrition Solutions

INTRODUCTION

Calcium chloride (CaCl₂) has been the only calcium additive available in the United States that has a low aluminum (Al) content. Calcium gluconate in glass vials (CaGluc-Gl) has a high Al content while calcium gluconate in plastic vials (CaGluc-Pl) has a low Al content. The purpose of this study was to measure Al concentrations in neonatal parenteral nutrition (PN) solutions prepared using various calcium additives.

METHODS

Samples of solutions compounded with CaCl₂ or CaGluc-Gl and sodium phosphate (NaPhos) as well as CaGluc-Pl and sodium glycerophosphate (NaGP) with and without cysteine were analyzed for Al content. Samples of the cysteine and calcium gluconate additives were also sent for analysis.

RESULTS

Solutions containing CaCl₂ and CaGlu-Pl had mean Al concentrations of 1.2-2.3 mcg/dL, while those with CaGlu-Gl had mean concentrations of 14.6-15.1 mcg/dL. Solutions made with NaGP were low in Al content. The measured Al content of 2 lots of the cysteine additive were 168 ± 23 mcg/L and 126 ± 5 mcg/L. The Al concentration equalled 2730 ± 20 mcg/L for the CaGlu-Gl additive and 310 ± 80 mcg/L for the CaGlu-Pl additive.

CONCLUSION

The study indicates that solutions containing CaCl₂ or CaGluc-Pl and NaPhos or NaGP are low in Al content. Using these options for calcium and phosphate additives can limit aluminum intake from neonatal PN to levels within the Food and Drug Administration guideline of ≤5 mcg/kg/d.

Development and evaluation of a test program for Y-site compatibility testing of total parenteral nutrition and intravenous drugs

Background

There is no standardized procedure or consensus to which tests should be performed to judge compatibility/incompatibility of intravenous drugs. The purpose of this study was to establish and evaluate a test program of methods suitable for detection of physical incompatibility in Y-site administration of total parenteral nutrition (TPN) and drugs.

Methods

Eight frequently used methods (dynamic light scattering, laser diffraction, light obscuration, turbidimetry, zeta potential, light microscopy, pH-measurements and visual examination using Tyndall beams), were scrutinized to elucidate strengths and weaknesses for compatibility testing. The responses of the methods were tested with samples containing precipitation of calcium phosphate and with heat destabilized TPN emulsions. A selection of drugs (acyclovir, ampicillin, ondansetron and paracetamol) was mixed with 3-in-1 TPN admixtures (Olimel® N5E, Kabiven® and SmofKabiven®) to assess compatibility (i.e. potential precipitates and emulsion stability). The obtained compatibility data was interpreted according to theory and compared to existing compatibility literature to further check the validity of the methods.

Results

Light obscuration together with turbidimetry, visual inspection and pH-measurements were able to capture signs of precipitations. For the analysis of emulsion stability, light obscuration and estimation of percent droplets above 5 μm (PFAT5) seemed to be the most sensitive method; however laser diffraction and monitoring changes in pH might be a useful support. Samples should always be compared to unmixed controls to reveal changes induced by the mixing. General acceptance criteria are difficult to define, although some limits are suggested based on current experience. The experimental compatibility data was supported by scattered reports in literature, further confirming the suitability of the test program. However, conflicting data are common, which complicates the comparison to existing literature.

Conclusions

Testing of these complex blends should be based on a combination of several methods and accompanied by theoretical considerations.

Calcium Chloride in Neonatal Parenteral Nutrition Solutions with and without Added Cysteine: Compatibility Studies Using Laser and Micro-Flow Imaging Methodology

BACKGROUND

Previous studies of compatibility of calcium chloride (CaCl2) and phosphates have not included particle counts in the range specified by the United States Pharmacopeia. Micro-flow imaging techniques have been shown to be comparable to light obscuration when determining particle count and size in pharmaceutical solutions.

OBJECTIVE

The purpose of this study was to do compatibility testing for parenteral nutrition (PN) solutions containing CaCl2 using dynamic light scattering and micro-flow imaging techniques.

METHODS

Solutions containing TrophAmine (Braun Medical Inc, Irvine, CA), CaCl2, and sodium phosphate (NaPhos) were compounded with and without cysteine. All solutions contained standard additives to neonatal PN solutions including dextrose, trace metals, and electrolytes. Control solutions contained no calcium or phosphate. Solutions were analyzed for particle size and particle count. Means of Z-average particle size and particle counts of controls were determined. Study solutions were compared to controls and United States Pharmacopeia (USP) Chapter 788 guidelines. The maximum amount of Phos that was compatible in solutions that contained at least 10 mmol/L of Ca in 2.5% amino acids (AA) was determined. Compatibility of these solutions was verified by performing analyses of 5 repeats of these solutions. Microscopic analyses of the repeats were also performed.

RESULTS

Amounts of CaCl2 and NaPhos that were compatible in solutions containing 1.5%, 2%, 2.5%, and 3% AA were determined. The maximum amount of NaPhos that could be added to TrophAmine solutions of > = 2.5% AA containing at least 10 mmol/L of CaCl2 was 7.5 mmol/L. Adding 50 mg/dL of cysteine increased the amount of NaPhos that could be added to solutions containing 10 mmol/L of CaCl2 to 10 mmol/L.

CONCLUSION

Calcium chloride can be added to neonatal PN solutions containing NaPhos in concentrations that can potentially provide an intravenous intake of adequate amounts of calcium and phosphorus.