Calcium, phosphorus and magnesium needs for the low-birth-weight infant.

Parental mineral-containing solutions for LBW infants should be started soon after birth. For the initiation of parenteral nutrition and during short-term therapy for less than 2 weeks' duration, LBW infants should receive parenteral nutrition solutions at rates of approximately 120-130 ml/kg/day, containing minerals at the following concentrations: Ca 15 mM, P 15 mM and Mg 2.5 mM. For optimal growth and nutrient utilization, however, LBW infants maintained on parenteral nutrition at rates of 120-130 ml/kg/day for 2 or more weeks should receive mineral concentrations of Ca 20 mM, P 20 mM and Mg 2.5 mM. In addition, these latter mixtures must contain amino acids in concentrations greater than or equal to 2.2 g% and cysteine-HCl must be provided. As newer formulations emerge, these recommendations may be modified. For human milk-fed LBW infants, after 1 week of enteral feeding, Ca and P should be supplied as fortifiers. Ca 2-3 mmol/kg/day and P 1.5-2.0 mmol/kg/day should be provided in addition to human milk. Magnesium supplementation of human milk is unnecessary. These recommendations assume that the intake of human milk is approximately 200 ml/kg/day and will decrease as more bioavailable mineral salts are found. For LBW infants fed commercial formula, the intake of Ca should be greater than 3.5 mmol/kg/day, P 2.5 mmol/kg/day and Mg 0.2 mmol/kg/day. These recommendations assume reported bioavailabilities of mineral salts. If more bioavailable sources are found, these recommendations will decrease.(ABSTRACT TRUNCATED AT 250 WORDS)