The kidneys are responsible for filtering certain components of blood and producing urine from them. In an adult, the kidneys are typically capable of processing about 1 to $1.5$ liters of water per hour depending on the individual and conditions within the body. In a condition known as water intoxication, a person ingests more water (usually 3 or more liters in a single sitting) in a shorter period of time than the kidneys can process. In a child, the amount of water required to induce water intoxication is much less. Of the options listed, what would be the best treatment for someone suffering from water intoxication?
A. administering a saline solution that is more concentrated than the cells
B. administering an isotonic solution
C. administering a solution low in solute concentration
D. performing dialysis to remove excess water from the plasma
Choose A, B, C or D as your solution.
The correct answer is $\mathrm{A}$. In this case, administering a solution that is hypertonic to the cells would help. A hypertonic extracellular solution would draw water out of the swollen cells to counteract the effects of water intoxication. An isotonic solution would not help. A solution low in solute concentration would be high in water relative to the cells making the solution hypotonic, which would cause more water to enter the cells. A saline solution would be high in solutes and hypertonic to the cells.