Sodium homeostasis in term and preterm neonates. III. Effect of salt supplementation.
Clinical and biochemical effects of supplementing dietary sodium intake to 4 to 5 mmol(mEq)/kg/day from days 4 to 14 of life were studied in 22 infants of gestational age 27 to 34 weeks. These infants were compared with a group of 24 unsupplemented babies. Supplemented infants lost less weight postnatally and regained birthweight more quickly: their improved weight gain continued after supplementation was stopped. Sodium balance was positive at age 5 to 11 days in supplemented babies but slightly negative in controls. Potassium balance was more strongly positive in the supplemented group. Plasma sodium concentration was higher in supplemented infants during weeks 3 and 4. Hyponatraemia was significantly more common in unsupplemented (37.5%) than supplemented (13.6%) infants. No infant became oedematous, hypernatraemic, or showed evidence of circulatory overload. The incidence of patent ductus arteriosus and necrotising enterocolitis was not increased; no intracranial haemorrhages occurred. Urinary potassium:sodium ratio was lower in supplemented babies than controls suggesting responsiveness of the distal tubule to mineralocorticoids. Providing 4 to 5 mmol(mEq)/kg/day of sodium to infants born before 34 weeks' gestation for the first two postnatal weeks improves growth and biochemical status and causes no undesirable side effects.
D001835:Body Weight / Q000187:drug effects; D006801:Humans; D007010:Hyponatremia / Q000517:prevention & control; D007231:Infant, Newborn; D007234:Infant, Premature; D011188:Potassium / Q000378:metabolism; D012964:Sodium / Q000378:metabolism*; D012965:Sodium Chloride / Q000009:adverse effects / Q000494:pharmacology / Q000627:therapeutic use; D014882:Water-Electrolyte Balance / Q000187:drug effects*
D012965:Sodium Chloride; D012964:Sodium; D011188:Potassium