title: Effects of alternate and simultaneous administrations of calcium and phosphorus on calcium metabolism in children receiving total parenteral nutrition.
abstract: The effects of alternate and simultaneous administrations of calcium (Ca) and phosphorus (P) on Ca metabolism in children receiving total parenteral nutrition (TPN) were examined. Eight children, aged 2 to 36 months, were studied. The following three solutions were administered: solution 1 contains Ca (533 mg/liter); solution 2 contains P (413 mg/liter); and solution 3 contains Ca (267 mg/liter) and P (207 mg/liter). Solutions 1 and 2 were administered alternately for 24-hr periods. (Results) I. During administration of solution 1, significant hypophosphatemia (4.39 +/- 0.26 mg/dl) and hypercalcemia (9.96 +/- 0.15 mg/dl) were observed and, conversely, during administration of solution 2, significant hypocalcemia (8.36 +/- 0.18 mg/dl) and hyperphosphatemia (6.16 +/- 0.27 mg/dl) were observed. During administration of solution 3, the serum levels of both minerals were maintained within the normal ranges (Ca 9.46 +/- 0.12 mg/dl, P 5.65 +/- 0.21 mg/dl). II. The urinary excretion of cyclic AMP was significantly lower during administration of solution 1 (6.67 +/- 0.45 nmol/mg creatinine (Cr] as compared with solution 3 (7.50 +/- 0.61 nmol/mg of Cr). On the other hand, the excretion was significantly higher during administration of solution 2 (11.55 +/- 1.58 nmol/mg of Cr) as compared with solution 3, indicating the existence of secondary hyperparathyroidism. III. The Ca and P retention rates were significantly higher with solution 3 (Ca 79.0 +/- 5.5%, P 73.2 +/- 7.2% of the intake) than with solutions 1 and 2 alternately (Ca 62.7 +/- 4.5%, P 49.2 +/- 9.3%). (Conclusions) Simultaneous administrations of Ca and P are preferable to their alternate administrations for Ca metabolism in children receiving TPN.
mesh_terms: D001842:Bone and Bones / Q000378:metabolism; D002118:Calcium / Q000008:administration & dosage* / Q000378:metabolism / Q000494:pharmacology; D002675:Child, Preschool; D000242:Cyclic AMP / Q000652:urine; D006801:Humans; D007223:Infant; D008297:Male; D010289:Parenteral Nutrition, Total; D010710:Phosphates / Q000097:blood; D010758:Phosphorus / Q000008:administration & dosage* / Q000378:metabolism / Q000494:pharmacology
chemical_list: D010710:Phosphates; D010758:Phosphorus; D000242:Cyclic AMP; D002118:Calcium