American journal of hospital pharmacy
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Factors affecting solubilities of calcium and phosphate in neonatal total parenteral nutrient (TPN) solutions containing a new amino acid formulation were examined. Twelve TPN solutions containing various concentrations of TrophAmine, an amino acid formulation specific for infants and young children, were prepared in 10% dextrose injection. Some of the solutions also contained cysteine hydrochloride 40 mg/g of protein and either sodium bicarbonate or hydrochloric acid (lipid emulsion buffer) to buffer the solution pH to simulate that produced by simultaneously administering lipid emulsion through the i.v. line. ⋯ Solubility curves were prepared by plotting graphically the concentrations at which either visual or microscopic precipitation occurred. Temperature, amino acid concentration, and the addition of cysteine hydrochloride and lipid emulsion buffer each influenced the solubilities of calcium and phosphate in the TPN solutions. The use of TrophAmine as the amino acid source allowed slightly greater concentrations of phosphate to be solubilized as compared with older amino acid formulations.(ABSTRACT TRUNCATED AT 250 WORDS)
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The sterility of trypticase soy broth (TSB) that was frozen and thawed in disposable plastic syringes and infused via syringe pump was studied to determine whether ambient air or personnel-transferred contaminants compromised the sterility of the solution. Samples of TSB (10, 20, 30 mL) were prepared aseptically in syringes of three different brands--150 samples for each volume (50 for each manufacturer). The syringes were placed in zip-lock bags, stored for 24 hours at -15 to -20 degrees C, and thawed for three hours. ⋯ There was no growth in any of the test infusion samples or in samples that were intentionally contaminated. The negative controls showed no growth; all of the positive controls showed growth. The sterility of solutions frozen in disposable plastic syringes does not appear to be compromised by touch contamination of the plunger shaft or by airborne microorganisms settling on the infusion system.