title: Sodium restriction versus daily maintenance replacement in very low birth weight premature neonates: a randomized, blind therapeutic trial.
abstract: To test the hypothesis that restriction of sodium intake during the first 3 to 5 days of life will prevent the occurrence of hypernatremia and the need for administration of large fluid volumes, we prospectively and randomly assigned 17 babies (mean +/- SD: 850 +/- 120 gm; 27 +/- 1 weeks of gestation) to receive in blind fashion either daily maintenance sodium or salt restriction with physician-prescribed parenteral fluid intake. Maintenance-group infants received 3 to 4 mEq of sodium per kilogram per day; restricted infants received no sodium supplement other than with such treatments as transfusion. Sodium balance studies conducted for 5 days demonstrated that maintenance salt intake resulted in a daily sodium balance near zero, whereas sodium-restricted infants continued to excrete urinary sodium at a high rate, which promoted a more negative balance (average daily sodium balance -0.30 +/- 1.78 SD in maintenance group vs -3.71 +/- 1.47 mEq/kg per day in restriction group; p less than 0.001). Care givers tended to prescribe daily increases in parenteral fluids for the salt-supplemented infants, perhaps because serum sodium concentrations were elevated in these infants after the first day of the study (p less than 0.001). Hypernatremia developed in two sodium-supplemented infants (greater than 150 mEq/L), and hyponatremia developed in two sodium-restricted infants (less than 130 mEq/L); however, the restricted infants were more likely to have normal serum osmolality (p less than 0.05). Both groups of infants produced urine that was neither concentrated nor dilute, with a high fractional excretion of sodium; renal failure was not observed. The mortality rate was not affected, but the incidence of bronchopulmonary dysplasia was significantly less in the sodium-restricted babies (p less than 0.02). We conclude that in tiny premature infants, a fluid regimen that restricts sodium may simplify parenteral fluid therapy targeted to prevent hypernatremia and excessive administration of parenteral fluids.
authors.affiliation: Department of Anesthesiology, University of Pennsylvania School of Medicine, Philadelphia.
authors.forename: A T
authors.initials: AT
authors.lastname: Costarino
authors.forename: J A
authors.initials: JA
authors.lastname: Gruskay
authors.forename: L
authors.initials: L
authors.lastname: Corcoran
authors.forename: R A
authors.initials: RA
authors.lastname: Polin
authors.forename: S
authors.initials: S
authors.lastname: Baumgart
mesh_terms: D005440:Fluid Therapy; D005919:Glomerular Filtration Rate; D006801:Humans; D006955:Hypernatremia / Q000517:prevention & control; D007010:Hyponatremia / Q000517:prevention & control; D007230:Infant, Low Birth Weight / Q000097:blood / Q000378:metabolism* / Q000652:urine; D007231:Infant, Newborn; D007234:Infant, Premature / Q000097:blood / Q000378:metabolism* / Q000652:urine; D007235:Infant, Premature, Diseases / Q000517:prevention & control; D009994:Osmolar Concentration; D011446:Prospective Studies; D016037:Single-Blind Method; D012964:Sodium / Q000008:administration & dosage* / Q000097:blood / Q000652:urine; D014882:Water-Electrolyte Balance
chemical_list: D012964:Sodium