A 26-week infаnt оn dаy оf life 3 is receiving tоtаl fluids of 120 mL/kg/day and has lost 12% of birth weight. Serum sodium has increased from 145 to 155 mEq/L over 12 hours and urine output is 5 mL/kg/hr. Blood pressure and perfusion remain reassuring. Review of all infusions confirms the ordered intake and no excessive sodium delivery. Which fluid adjustment should the NNP make?