title: Urinary acidification in extremely low birth weight infants.
abstract: Premature infants often present metabolic acidosis without protein load in the early neonatal period, around days 4-6. In order to elucidate the cause of acidosis, we investigated urinary acidification of infants in the early neonatal period. Urine pH, fractional excretion of HCO(3)(-) (FEHCO(3)), excretion of HCO(3)(-) and NH(4)(+) of the appropriate-for-date infants were measured on days 0-2 and on days 4-6 of life. Extremely low birth weight (ELBW) infants showed higher urine pH than more than 1500 g birth weight infants. FEHCO(3) and HCO(3)(-) excretion were of high values in ELBW infants on days 0-2, but decreased on days 4-6. Urine NH(4)(+) excretion rate was lower in ELBW infants than in birth weight more than 1000 g on days 0-2 of life and still remained at a low rate on days 4-6. These data indicated that insufficiency of NH(4)(+) excretion is the main cause for metabolic acidosis of ELBW infants in the early neonatal period.
authors.affiliation: Department of Pediatrics, Niigata University, 1-757, Asahimachi, Niigata, 951-8510, Niigata, Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Sato
authors.forename: Naoto
authors.initials: N
authors.lastname: Takahashi
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Komatsu
authors.forename: Masaki
authors.initials: M
authors.lastname: Wada
authors.forename: Masamichi
authors.initials: M
authors.lastname: Matsunaga
authors.forename: Katsumi
authors.initials: K
authors.lastname: Ito
authors.forename: Makoto
authors.initials: M
authors.lastname: Uchiyama
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Nishida
mesh_terms: D000138:Acidosis / Q000188:drug therapy / Q000652:urine*; D001639:Bicarbonates / Q000652:urine; D005865:Gestational Age; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007231:Infant, Newborn; D007234:Infant, Premature; D019102:Infant, Very Low Birth Weight / Q000097:blood / Q000652:urine*; D007262:Infusions, Intravenous; D000644:Quaternary Ammonium Compounds / Q000652:urine; D017693:Sodium Bicarbonate / Q000008:administration & dosage / Q000627:therapeutic use
chemical_list: D001639:Bicarbonates; D000644:Quaternary Ammonium Compounds; D017693:Sodium Bicarbonate