The primary healthcare provider prescribes a hypotonic IV solution. Which solution will the nurse administer?

A hypotonic IV solution is one that has a lower osmolarity than blood plasma, which means it can help to rehydrate cells and tissues by moving water into the cells. Among the options provided, a 0.45% Normal Saline solution fits this definition perfectly, as it contains a lower concentration of sodium chloride compared to the body’s plasma.

When this type of solution is administered, it can cause fluid to shift from the extracellular space into the intracellular space, effectively hydrating cells and potentially addressing conditions such as hypernatremia or dehydration.

Dextrose 5% in Lactated Ringer's, while it does contain some hypotonicity due to the dextrose, is generally more isotonic or slightly hypertonic when the dextrose is metabolized, and this can affect fluid distribution differently in the body. Normal Saline (0.9% NaCl) is isotonic and does not shift fluid into cells as effectively as a hypotonic solution. Plasma expanders are also not categorized as hypotonic solutions; they are usually used to increase blood volume rather than to hydrate cells specifically.

Thus, the selection of a hypotonic IV solution is crucial for ensuring appropriate fluid balance and cellular hydration,