The effect of parenteral nitrogen and energy intake on electrolyte balance in the preterm infant

• Published in: European journal of clinical nutrition Vol. 65; no. 10; pp. 1088 - 1093
• Main Authors: Bonsante, F, Iacobelli, S, Chantegret, C, Martin, D, Gouyon, J-B
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 01.10.2011; Nature Publishing Group
• Subjects: 631/443/319/1557; 692/700/1720; 692/700/565/2072; Amino acids; Amino Acids - administration & dosage; Anesthesia. Intensive care medicine. Transfusions. Cell therapy and gene therapy; Babies; Bioenergetics; Biological and medical sciences; Body weight; Body weight loss; Catabolism; Clinical Nutrition; Electrolyte balance; Electrolytes; Electrolytes - blood; Electrolytes - urine; Emergency and intensive care: metabolism and nutrition disorders. Enteral and parenteral nutrition; Energy Intake; Energy metabolism; Epidemiology; Feeding. Feeding behavior; Fetuses; Food and nutrition; Food intake; Fundamental and applied biological sciences. Psychology; Homeostasis; Homeostasis - drug effects; Humans; Hyperkalemia; Hyperkalemia - physiopathology; Hyperkalemia - prevention & control; Infant; Infant, Newborn; Infant, Premature - metabolism; Infants; Infants (Premature); Intensive care medicine; Internal Medicine; Intracellular; Linear Models; Medical sciences; Medicine; Medicine & Public Health; Metabolic Diseases; Multivariate Analysis; Nitrogen - administration & dosage; Nutrient balance; Nutrition; original-article; Osmoregulation; Parenteral feeding; Parenteral nutrition; Parenteral Nutrition - standards; Parenteral therapy; Physiological aspects; Potassium, Dietary - administration & dosage; Potassium, Dietary - metabolism; Premature birth; Prospective Studies; Public Health; Sodium; Sodium, Dietary - administration & dosage; Sodium, Dietary - metabolism; Urine; Vertebrates: anatomy and physiology, studies on body, several organs or systems; Water content; Water-Electrolyte Balance; Water-electrolyte balance (Physiology); Weight loss; Weight Loss - drug effects; Weight reduction; France; sodium balance; aggressive parenteral nutrition; amino acid; Na/K-ATPase; intracellular water compartment; potassium balance; Water; Energy input; K; Inorganic element; Na; Enzyme; Metabolic diseases; Parenteral nutrition; Nitrogen; Parenteral administration; Energy balance; Electrolyte; Prematurity; Sodium; Aminoacid; Hydrolases; exchanging ATPase; Intracellular; Potassium; preterm; guidelines; metabolism; fluid; urea
• ISSN: 0954-3007; 1476-5640
• DOI: 10.1038/ejcn.2011.79

Background/Objectives: Recent guidelines for preterm parenteral nutrition (PN) recommend an earlier and higher intake of amino acids (AA) and energy to avoid postnatal catabolism and approximate normal fetal growth. Few investigations explored how early PN may affect electrolyte and water homeostasis. We performed a prospective observational trial to assess the effect of nutrient intake on electrolyte homeostasis and balance. Subjects/Methods: During 16 months, all infants ⩽32 weeks were eligible. In the first week of life, we recorded the following daily: electrolytes (plasma and 8-h urine collection), nutritional intake, urine output, body weight, and we calculated sodium (Na) and potassium (K) balance. Infants were divided, for analysis, into three groups of AA intake: low <1.5 g/kg/day (LAA), medium 1.5–2 g/kg/day (MAA) and high >2 g/kg/day (HAA). Results: A total of 154 infants were included. HAA group presented lower weight loss. Na balance was influenced by urine output and postnatal age, with little contribution of nutrition. Kalemia and K balance were mainly influenced by AA intake. K balance differed among groups: LAA, −2.3 mmol/kg/week; MAA, 1.1 mmol/kg/week; and HAA 2.6 mmol/kg/week ( P <0.0001). In the HAA group, plasma and urine K were significantly lower and non-oliguric hyperkalemia was reduced. Conclusions: Na homeostasis was very slightly modified by early nutrition, suggesting that a negative Na balance is obligatory after birth. We showed that AA intake strongly affects K balance, minimize hyperkalemia and reduces weight loss. As K balance is strictly linked to cellular metabolism, we speculate that early nutrition may inhibit cellular catabolism and reduce the contraction of intracellular water compartment.