Fluid and electrolyte intake during the first week of life in preterm infants receiving parenteral nutrition according current guidelines.

There is growing evidence that early water and electrolyte homeostasis may be influenced by energy balance in preterm infants. Some fluid and electrolyte disturbances of postnatal life could be in part promoted by the catabolism due to withheld amino acid and energy supply after birth. According to current guidelines parenteral nutrition with relatively high protein and lipid needs is commenced on day one. By turning the nitrogen balance from negative to zero or even positive, amino acid administration could also minimize the occurrence of water and ions disturbances after birth especially in extremely preterm infants. Future researches are needed in order to further investigate the impact of amino acid and energy intake on early fluid balance in preterm infants.