NOTE: The authors refer to references 166 and 167 but the reference list does not go to that high a number.
Parameters:
(1) protein content in grams per liter
(2) sodium concentration in mmol/L
(3) potassium concentration in mmol/L
(4) chloride concentration in mmol/L
(5) volume of formula given in mL per kg per day (assuming fluid balance)
(6) estimate of insensible water and stool water loss in mL per kg per day
potential renal solute load in mOsm from daily intake of formula =
= ((4 * (protein)) + (sodium) + (potassium) + (chloride)) * (formula in mL per kg per day) / 1000
water available for urine in mL per kg per day =
= (volume of formula) - (insensitive water loss)
where:
• The formula estimates that the renal solute load from dietary protein is 4 mOsm per g. Other authors use a different factor.
estimated urine osmolality in mOsm per kg water =
= (potential renal solute load) / (water volume available in mL) * 1000
