Which of the following is true concerning pediatric patients?
A. Total body water is highest (60%) at six months of age
B. Extracellular water (ECW) increases from 43% to 62% between the first trimester and a term infant
C. Estimated blood volume by weight (ml/kg) is higher in a term infant compared to a premature infant.
D. Adult glomerular filtration rate (GFR) is achieved by 2 years of age
The answer is D. TBW is highest in the newborn (78%). ECW DECREASES from 62% to 43% from the first trimester to term. Also, ICW increases from 25% to 32% during the same time. Because the ratio of surface area to volume is decreasing, the ECW and plasma volumes remain constant AS A FUNCTION OF SURFACE AREA, but not weight. Therefore, estimates of blood volume (EBV) by weight change with age. These estimates are highest in the premature infant (100ml/kg) decreasing to 90 ml/kg at term.[1].==Notes==