In the full-term neonate
a) Total body water constitutes 65% of body weight
b) Intracellular fluid constitutes a greater proportion of total body water than extracellular fluid
c) Extracellular fluid represents 45% of body weight
d) Intracellular fluid represents 70% of body weight
Answer c.
In a term neonate, total body water accounts for 80% of body weight. Extracellular fluid constitutes 45% of body weight. Intracellular fluid constitutes 35% of body weight. At all ages, the extracellular component constitutes a greater proportion of total body water than intracellular fluid. These relationships are important it terms of their effects on drug volume of distribution