Physical Compatibility of Sodium Glycerophosphate and Calcium Gluconate in Pediatric Parenteral Nutrition Solutions.
BACKGROUND
The solubility of inorganic calcium and phosphate in parenteral solutions can be complicated in pediatrics due to the dosing of calcium and phosphorus at the saturation point. The purpose of this study was to test the solubility of sodium glycerophosphate (NaGP) with calcium gluconate in pediatric parenteral nutrition (PN) solutions.


METHODS
Five PN solutions were compounded by adding calcium gluconate at 10, 20, 30, 40, and 50 mEq/L and corresponding concentrations of NaGP at 10, 20, 30, 40, and 50 mmol/L. Each of the 5 solutions was compounded using 1.5% and 4% amino acids, cysteines, and lipids. Compatibility was evaluated by visual inspection (precipitation, haze, and color change). Solutions were evaluated microscopically for any microcrystals and measured by a turbidimeter for changes in turbidity. Solutions were further analyzed using United States Pharmacopeia 788 standards. Six hundred seventy-one PN solutions were compounded at various concentrations and evaluated for visual stability.


RESULTS
Compatibility testing showed no changes in the PN solution in any of the concentrations tested. Microscopically, no microcrystals were detected. The turbidimeter measurements had changes of ≤ 0.14 nephelometric turbidity units for all test solutions. There were no visual changes in any of the 671 PN solutions.


CONCLUSIONS
It is recommended that NaGP replace sodium phosphate in PN solutions. This would eliminate the concern of calcium and phosphorus precipitation and the need of any saturation curves.
Primary Children's Hospital, Salt Lake City, Utah mark.mackay@imail.org.
Mark
M
MacKay
Primary Children's Hospital, Salt Lake City, Utah.
Collin
C
Anderson
D002118:Calcium / Q000737:chemistry; D002125:Calcium Gluconate / Q000737:chemistry*; D011232:Chemical Precipitation; D003545:Cysteine / Q000032:analysis; D004305:Dose-Response Relationship, Drug; D005994:Glycerophosphates / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D057947:Parenteral Nutrition Solutions / Q000737:chemistry*; D010710:Phosphates / Q000737:chemistry; D010758:Phosphorus / Q000737:chemistry; D012995:Solubility; D014815:Vitamins / Q000032:analysis
D005994:Glycerophosphates; D057947:Parenteral Nutrition Solutions; D010710:Phosphates; D014815:Vitamins; D010758:Phosphorus; C029620:alpha-glycerophosphoric acid; D003545:Cysteine; C018279:sodium phosphate; D002125:Calcium Gluconate; D002118:Calcium
compatibility; parenteral nutrition; sodium glycerophosphate