Question

If they gave IVs of pure water in the emergency room to people who are dehydrated, what would happen?

Answer 1

Answer:

The correct answer is: B. blood cells would be in a hypotonic solution, so water would rush into the cell causing it to expand and eventually burst.

Explanation:

Cells have a certain solute concentration that produces an osmotic pressure of aproximately 300 mOsm. For that reason, IVs solutions must have a solute concentration which equals the cell osmotic pressure. That is usually acomplished by using an aqueous solution of NaCl 0.9% w/v or 5% w/v Glucose.

If an IV of pure water is administrated to a person, the blood cells will be in a hypotonic solution. That is, with a concentration lesser than the concentration inside the cells. Due to the difference in concentration, a net flow of water will be produced from the exterior to the cell interior. As the volume of the cell is increased, the cell membrane is damaged and eventually the cell will collapse.